Peripherally Administered Botulinum Toxin Type A Localizes Bilaterally in Trigeminal Ganglia of Animal Model


Dentin-pulp complex tissue regeneration via three-dimensional cell sheet layering

The dentin-pulp complex is a unique structure in teeth that contains both hard and soft tissues. Generally, deep caries and trauma cause damage to the dentin-pulp complex, and if left untreated, this damage will progress to irreversible pulpitis. The aim of this study was to fabricate a layered cell sheet composed of rat dental pulp (DP) cells and odontogenic differentiation of pulp (OD) cells and to investigate the ability to regenerate the dentin-pulp complex in a scaffold tooth. We fabricated two single cell sheets composed of DP cells (DP cell sheet) or OD cells (OD cell sheet) and a layered cell sheet made by layering both cells. The characteristics of the fabricated cell sheets were analyzed using light microscopy, scanning electron microscope (SEM), hematoxylin-eosin (HE) staining, and immunohistochemistry (IHC). Furthermore, the cell sheets were transplanted into the subrenal capsule of immunocompromised mice for 8 weeks. After this, the regenerative capacity to form dentin-like tissue was evaluated using micro-computed tomography (micro-CT), HE staining, and IHC. The findings of SEM and IHC confirmed that layered cell sheets fabricated by stacking OD cells and DP cells maintained their cytological characteristics. Micro-CT of layered cell sheet transplants revealed a mineralized capping of the access cavity in the crown area, similar to that of natural dentin. In contrast, the OD cell sheet group demonstrated the formation of irregular fragments of mineralized tissue in the pulp cavity, and the DP cell sheet did not develop any hard tissue. Moreover, bone volume/tissue volume (BV/TV) showed a significant increase in hard tissue formation in the layered cell sheet group compared with that in the single cell sheet group ( < 0.05). HE staining also showed a combination of soft and hard tissue formation in the layered cell sheet group. Furthermore, IHC confirmed that the dentin-like tissue generated from the layered cell sheet expressed characteristic markers of dentin but not bone equivalent to that of a natural tooth. In conclusion, this study demonstrates the feasibility of regenerating dentin-pulp complex using a bioengineered tissue designed to simulate the anatomical structure. Impact statement The dentin-pulp complex can be destroyed by deep caries and trauma, which may cause pulpitis and progress to irreversible pulpitis, apical periodontitis, and even tooth loss. Current treatments cannot maintain pulp health, and teeth can become brittle. We developed a three-dimensional (3D) layered cell sheet using dental pulp cells and odontogenic differentiation of pulp cells for dentin-pulp complex regeneration. Our layered cell sheet enables the regeneration of an organized 3D dentin-pulp-like structure comparable with that of natural teeth. This layered cell sheet technology may contribute to dentin-pulp complex regeneration and provide a novel method for complex tissue engineering.


Risk factors for tooth loss in patients with 25 remaining teeth undergoing mid-long-term

International Journal of Environmental Research and Public Health


Pain sensitivity increases with sleep disturbance under predictable chronic mild stress in mice


Effects of sitting posture and jaw clenching on neck and trunk muscle activities during typing

Neck pain is one of the most common musculoskeletal complaints. Evidence suggests that increased activities of neck and trunk muscles are one of the mechanisms related to neck pain. Jaw clenching and sitting posture may modulate the muscle activity in neck and trunk muscles during typing. The present study aimed to assess the effects of different postural positions and clenching conditions on neck and trunk muscle activities. Thirteen healthy adults (39.8 ± 5.0 years) performed computer typing tasks in four conditions (two postural positions [upright vs slouched] and two jaw clenching conditions [clenching vs non-clenching]). Integrated surface electromyography (iEMG) was measured in sternocleidomastoid (SCM), upper trapezius (uTP) and middle trapezius (mTP) muscles and compared between conditions. The Friedman and Wilcoxon signed-rank tests with Bonferroni's corrections were used to estimate the condition-specific differences in the iEMG data. The statistical significance level was set at 5%. In both postural positions, iEMG was significantly greater under the jaw clenching than under the non-clenching condition (χ = 21.700, P < .01). Under both jaw clenching conditions, iEMG was significantly greater in the slouched than in the upright postural position (χ = 23.182, P < .01). No significant differences in iEMG were seen across conditions (χ = 5.018, P = .10). Sitting posture and jaw clenching appear to influence activities of different muscles.


Immediate Effect of Masticatory Muscle Activity with Transcutaneous Electrical Nerve Stimulation in Muscle Pain of Temporomandibular Disorders Patients

Transcutaneous electrical nerve stimulation (TENS) is a non-invasive treatment modality for acute and chronic pain. However, little information for muscle activity is available on the immediate effects of TENS in masticatory muscle pain related to temporomandibular disorders (TMDs). The present study aimed to evaluate the immediate effects of TENS treatment on TMD-related muscle pain. Thirty-six patients with TMD-related muscle pain and 39 healthy subjects served as TMD and control groups, respectively. For objective evaluations, maximum mouth opening, and maximum bite force were measured before and after TENS. The pain intensity was assessed according to a 100-mm visual analog scale (VAS). TENS was applied to painful muscles for 20 min with frequencies of 100-200 Hz. The treatment outcome was evaluated using Global Rating of Change (GRC) scales. In the TMD group, VAS values significantly decreased after TENS. Although there was significant increase in the maximum mouth opening after TENS for only TMD group, the maximum bite force of both groups was significantly greater after TENS. According to GRC scales, one patient with TMD-related muscle pain expressed negative feelings after TENS. Conclusively, TENS treatment might quickly relieve pain in masticatory muscles and improve masticatory functions in patients with TMD-related muscle pain.


Evaluation of the measurement precision and accuracy in the dental CAD/CAM system

The purpose of this study is to investigate the precision and trueness of the occlusal contact record obtained with a dental CAD/CAM device (ARCTICA). Sandblasted spherical steel balls with diameters of 10-20 mm were measured using ARCTICA and a three-dimensional measurement device (FN503). The radius of each steel ball was calculated from the measured value and the difference between the measured and nominal values was obtained. Upper/lower dental arch casts were measured and processed for occlusal contact image creation using both devices. The graphical images of the occlusal contacts at the intercuspal position obtained from both systems and an occlusal analysis device (BE-1) were compared with the occlusal contact area. Excellent correlation was observed between the measurement results of ARCTICA and FN503 (p<0.001, R: 0.99). The occlusal contact areas were 186.0 mm (ARCTICA), 192.8 mm (FN503), and 196.1 mm (BE-1). This study showed that ARCTICA is capable of conducting highly accurate measurements and generating a graphical image of occlusal contacts with good reliability.


Risk factors for tooth loss in patients undergoing mid long-term maintenance: A retrospective study

In this retrospective study, we identified risk factors for tooth loss in patients undergoing mid-long-term maintenance therapy. We surveyed 674 maintenance patients for ≥5 years after active treatment who visited a dental clinic between January 2015 and December 2016. Of these, 265 were men (mean age 54.6 ± 8.0 years old) and 409 were women (mean age 54.0 ± 7.9 years old). Study variables included patient compliance, sex, number of teeth lost, cause of tooth loss (dental caries, periodontal disease, root fracture, others, vital or non-vital teeth), age at start of maintenance, number of remaining teeth at start of maintenance, smoking, use of salivary secretion inhibitors, presence of diabetes mellitus, condition of periodontal bone loss, and use of a removable denture. Most lost teeth were non-vital teeth (91.7% of all cases) and the most common cause of tooth loss was tooth fracture (62.1% of all cases). A statistically significant risk factors for tooth loss was number of remaining teeth at the start of maintenance ( = 0.003).


Role of CGRP in neuroimmune interaction via NFkB signalling genes in glial cells of trigeminal ganglia

Activation of the trigeminal system causes the release of various neuropeptides, cytokines, and other immune mediators. Calcitonin gene-related peptide (CGRP), which is a potent algogenic mediator, is expressed in the peripheral sensory neurons of trigeminal ganglion (TG). It affects the inflammatory responses and pain sensitivity by modulating the activity of glial cells. The primary aim of this study was to use array analysis to investigate the effect of CGRP on the glial cells of TG in regulating nuclear factor kappa B (NF-κB) signaling genes and to further check if CGRP in the TG can affect neuron-glia activation in the spinal trigeminal nucleus caudalis. The glial cells of TG were stimulated with CGRP or Minocycline (Min) + CGRP. The effect on various genes involved in NF-κB signaling pathway was analyzed compared to no treatment control condition using a PCR array analysis. CGRP, Min + CGRP or saline was directly injected inside the TG and the effect on gene expression of , and and protein expression of cleaved Caspase3 (cleav Casp3) in the TG, and c-Fos and glial fibrillary acidic protein (GFAP) in the spinal section containing trigeminal nucleus caudalis was analyzed. Results showed that CGRP stimulation resulted in the modulation of several genes involved in the interleukin 1 signaling pathway and some genes of the tumor necrosis factor pathway. Minocycline pre-treatment resulted in the modulation of several genes in the glial cells, including anti-inflammatory genes, and neuronal activation markers. A mild increase in cleav Casp3 expression in TG and c-Fos and GFAP in the spinal trigeminal nucleus of CGRP injected animals was observed. These data provide evidence that glial cells can participate in neuroimmune interaction due to CGRP in the TG via NF-κB signaling pathway.

International Journal of Molecular Sciences


Comparative analysis of education, awareness, and knowledge of dentists and physical therapists in the treatment of temporomandibular disorders

To compare the education, awareness, and knowledge of Filipino dentists and physical therapists (PTs) in terms of temporomandibular disorders (TMDs). A 30-item structured online questionnaire was given to recruited PTs and dentists from January 2019 to December 2019. Welch's -test was used to compare the education, awareness, and knowledge of health professionals. Brown-Forsythe and Welch ANOVA with Games-Howell post hoc were used to compare test scores across the knowledge components. Of the 620 professionals, 46.67% dentists and 6.38% PTs had training in TMD. Professionals with more years of experience and who had previous TMD training were more aware of TMD management. Both dentists and PTs showed the lowest knowledge in TMD pathophysiology. This study showed high awareness but low education and knowledge of Filipino dentists and PTs in TMD management. Improving the educational curriculum and refining the training given by accredited professional organizations is suggested.


Analysis of the Filipinos interest in searching online for oral cancer

This study analyzed the health-seeking behavior of Filipinos through relative search volume in Google Trends using oral cancer, mouth cancer, tongue cancer, gum cancer, and lip cancer as predetermined search terms. Comma-separated values files containing relative search volumes of search trends pertaining to oral cancer from 2009 to 2019 were assessed. Brown-Forsythe one-way ANOVA was used to measure differences of oral cancer between years and among months. Repeated measures two-way ANOVA measured differences among the searches for mouth cancer, tongue cancer, gum cancer, and lip cancer through the years. Time series models were fitted and used to forecast search interests. The results revealed that interests in oral cancer were significantly higher in 2019 (43.75±5.5, p<0.05) compared to 2009 (29.0 ± 6.7). In terms of months, searches were higher in February (45.0 ± 6.6) compared to May (24.8 ± 3.4, p=0.015), June (25.3 ± 4.4, p=0.020), and December (26.5 ± 4.0, p=0.038). Search interests for gum cancer and lip cancer remained significantly lower from 2011 to 2019, and tongue cancer from 2016 to 2018 but approximated mouth cancer in 2019. The forecast shows mouth cancer (31.67%), tongue cancer (23.75%), and lip cancer (3.83%) fluctuating through the year, while gum cancer (8%) will remain steady in 2020. Health-seeking behavior through search trends show an increased interest in oral cancer in 2019 and during February. Search interests will fluctuate in 2020, but at the end of the year will decrease for mouth cancer and tongue cancer, will increase for lip cancer, and will remain steady for gum cancer.

Asian Pacific Journal of Cancer Prevention : APJCP


Three-dimensional periodontal tissue regeneration using a bone-ligament complex cell sheet

Periodontal tissue is a distinctive tissue structure composed three-dimensionally of cementum, periodontal ligament (PDL) and alveolar bone. Severe periodontal diseases cause fundamental problems for oral function and general health, and conventional dental treatments are insufficient for healing to healthy periodontal tissue. Cell sheet technology has been used in many tissue regenerations, including periodontal tissue, to transplant appropriate stem/progenitor cells for tissue regeneration of a target site as a uniform tissue. However, it is still difficult to construct a three-dimensional structure of complex tissue composed of multiple types of cells, and the transplantation of a single cell sheet cannot sufficiently regenerate a large-scale tissue injury. Here, we fabricated a three-dimensional complex cell sheet composed of a bone-ligament structure by layering PDL cells and osteoblast-like cells on a temperature responsive culture dish. Following ectopic and orthotopic transplantation, only the complex cell sheet group was demonstrated to anatomically regenerate the bone-ligament structure along with the functional connection of PDL-like fibers to the tooth root and alveolar bone. This study represents successful three-dimensional tissue regeneration of a large-scale tissue injury using a bioengineered tissue designed to simulate the anatomical structure.


Association of masticatory muscle activity with sleep arousal and other concomitant movements during sleep

This study aims to verify the associations among sleep bruxism (SB), sleep arousal (SA) and concurrent body movements. Subjects underwent a standard overnight polysomnography test and audio-video recordings. Sleep quality was evaluated according to the Rechtschaffen and Kales criteria, while SA was determined as per the American Sleep Disorders Association criteria. Analyses were performed by an external institution after masking of the subjects' information. SB was assessed based on the presence/absence of rhythmic masticatory muscle activity (RMMA) episodes, which were identified by using electromyography of the masseter muscle. The observed simultaneous movements included lower leg movement (LLM), swallowing, face scratching, head movement, body movement, eye blinking, coughing, licking, sighing, body scratching, lip sucking, somniloquy and yawning. The LLM was determined visually, as well as through an increase in the tibialis electromyogram signal. Other movements were visually assessed using audio-video recordings. The incidences of all the simultaneous movements were compared between RMMA with intercurrent SA (SAwRMMA; RMMA episode derived from a masseter electromyogram showing more than 10% of maximum voluntary contraction) and SA without RMMA (SAw/oRMMA). Fourteen subjects were included in this study (females/males: 4/10, mean age: 31.5 ± 5.7 years). Among these, LLM, swallowing, body movement, licking, body scratching and lip sucking were frequently observed in SAwRMMA episodes than in SAw/oRMMA episodes, significantly. However, the non-specific simultaneous movements were higher observed in SAw/oRMMA episodes than that in SAwRMMA. Our results suggest that SB is concurrently activated with LLM in relation to arousal.


The role of chemical transmitters in neuron-glia interaction and pain in sensory ganglion

Neuropathic pain (NP) develops because of damage to the peripheral or central nervous system. It results in the hyperalgesia and allodynia. In the recent years, various researchers have studied the involvement of neuro-immune system in causing persistence of pain. The absence of synaptic contacts in the sensory ganglion makes them distinctive in terms of pain related signalling. In sensory ganglia, the neurotransmitters or the other modulators such as inflammatory substances produced by the ganglion cells, because of an injury, are responsible for the cross-excitation between neurons and neuron-glial interaction, thus affecting chemical transmission. This chemical transmission is considered mainly responsible for the chronicity and the persistent nature of neuropathic pain. This review examines the pain signalling due to neurotransmitter or cytokine release within the sensory ganglia. The specific areas focused on include: 1) the role of neurotransmitters released from the somata of sensory neurons in pain, 2) neuron-glia interaction and 3) role of cytokines in neuromodulation and pain.


The evolution of dental education in the Philippines


IL-10 and CXCL2 in trigeminal ganglia in neuropathic pain


The effects of exercise therapy on painful temporomandibular disorders


Quality of life and job satisfaction among female dentists in Japan


CGRP induces differential regulation of cytokines from satellite glial cells in trigeminal ganglia and orofacial nociception

Neuron-glia interactions contribute to pain initiation and sustainment. Intra-ganglionic (IG) secretion of calcitonin gene-related peptide (CGRP) in the trigeminal ganglion (TG) modulates pain transmission through neuron-glia signaling, contributing to various orofacial pain conditions. The present study aimed to investigate the role of satellite glial cells (SGC) in TG in causing cytokine-related orofacial nociception in response to IG administration of CGRP. For that purpose, CGRP alone (10 μL of 10 M), Minocycline (5 μL containing 10 μg) followed by CGRP with one hour gap (Min + CGRP) were administered directly inside the TG in independent experiments. Rats were evaluated for thermal hyperalgesia at 6 and 24 h post-injection using an operant orofacial pain assessment device (OPAD) at three temperatures (37, 45 and 10 °C). Quantitative real-time PCR was performed to evaluate the mRNA expression of IL-1β, IL-6, TNF-α, IL-1 receptor antagonist (IL-1RA), sodium channel 1.7 (NaV 1.7, for assessment of neuronal activation) and glial fibrillary acidic protein (GFAP, a marker of glial activation). The cytokines released in culture media from purified glial cells were evaluated using antibody cytokine array. IG CGRP caused heat hyperalgesia between 6-24 h (paired- test, < 0.05). Between 1 to 6 h the mRNA and protein expressions of GFAP was increased in parallel with an increase in the mRNA expression of pro-inflammatory cytokines IL-1β and anti-inflammatory cytokine IL-1RA and NaV1.7 (one-way ANOVA followed by Dunnett's post hoc test, < 0.05). To investigate whether glial inhibition is useful to prevent nociception symptoms, Minocycline (glial inhibitor) was administered IG 1 h before CGRP injection. Minocycline reversed CGRP-induced thermal nociception, glial activity, and down-regulated IL-1β and IL-6 cytokines significantly at 6 h (-test, < 0.05). Purified glial cells in culture showed an increase in release of 20 cytokines after stimulation with CGRP. Our findings demonstrate that SGCs in the sensory ganglia contribute to the occurrence of pain via cytokine expression and that glial inhibition can effectively control the development of nociception.

International Journal of Molecular Sciences


Cross-sectional observational study exploring clinical risk of titanium allergy caused by dental implants

Studies have reported cases of metal allergy caused by titanium-containing materials. We wished to clarify the relationship between titanium allergy and dental implants by describing patients who suffered allergic symptoms after they had received such implants. A total of 270 patients who visited a Dental Metal Allergy Clinic at Tokushima University Hospital from April 2010 to March 2014 were the study cohort. Patch testing with 28 types of metal allergens (including four titanium allergens) was undertaken for patients. A total of 217 patients (80.4 %) exhibited allergy-positive reactions to at least one type of metal allergen. Mercury, palladium, chromium and nickel exhibited a higher prevalence of allergy-positive reactions than other metals. Sixteen patients visited our clinic suffering allergic symptoms after receiving dental implants. Eleven of those patients exhibited allergy-positive reactions for any of the metal allergens, and 4 of these patients had allergy-positive reactions against titanium allergens. The total number of allergy-positive reactions for titanium allergens among all 270 patients was 17 (6.3 %). No patient exhibited a positive reaction only for the titanium allergen. The prevalence of allergy-positive reactions for titanium allergens was lower than for other metal allergens. We suggest examination of pre-implant patients who have a history of hypersensitivity reactions to metals.


Investigation of behavioural factors which vary occlusal contact in Japanese dental students

The Journal of Japanese Society of Stomatognathic Function


Posterior disc displacement of the temporomandibular joint -a rare case report

Posterior disc displacement (PDD) of the temporomandibular joint (TMJ) is quite rare. The normal position of a disc is slightly anterior to the condyle, so the chances of disc displacement to the posterior direction are low. A 71-year-old Japanese female reported with a chief complaint of lack of occlusion on the right-side molar teeth. Clinical examination revealed lack of occlusal contact in the right posterior region, nearly normal range of mouth opening (41.0 mm), masseter muscle tenderness, and deviation to the left on opening. MRI of the right TMJ showed PDD in both the open- and closed-mouth position and joint effusion. Conservative treatment with a non-steroidal anti-inflammatory drug, stretch exercise with fingers, and stabilization splint improved symptoms for 9 months. Conservative treatment was effective in managing the patient. A follow-up for 9 months with a repeat MRI was undertaken to monitor the progress.


Metal allergy patient treated by titanium implant denture: A case report with at least 4-year follow-up

Patch testing with metal reagents was positive on female patient with history of metal hypersensitivity after dental treatment. All of the dental restorations with metal components were removed, and subsequent oral rehabilitation utilizing dental implants and metal-free prostheses was carried out. The treatments alleviate the presenting signs and symptoms.


Prevalence of posterior disc displacement of the temporomandibular joint in patients with temporomandibular disorders: a systematic review with meta-analysis

To assess the prevalence of posterior disc displacement (PDD) in patients with temporomandibular disorders (TMD) through a systematic review of the literature and meta-analysis, as well as to assess features associated with PDD such as chief complaint, signs and symptoms, morphologic condyle and disc alterations, and PDD management. A systematic literature search was performed in the US National Library of Medicine's PubMed/MEDLINE and Cochrane Library databases to identify all peer-reviewed, English-language manuscripts related to PDD. A critical appraisal checklist provided by the Joanna Briggs Institute for studies reporting prevalence data was used to assess the quality of the included manuscripts. A meta-analysis was conducted using software MetaXL 5.3 (EpiGear International Pty Ltd) add-in for Microsoft Excel. Pooled prevalence and 95% confidence intervals (CIs) were calculated using the software. Heterogeneity of the included studies was assessed using the Higgins I test and Cochran's Q (with P value; < .05 was considered significant). A total of 21 articles were selected for qualitative data synthesis: 2 case reports, 14 observational studies, and 5 studies that reported PDD in various conditions. Quantitative data analysis was performed for the 14 observational studies, of which 13 reported prevalence with respect to the number of joints affected and 9 reported prevalence with respect to the number of patients affected. The overall pooled prevalence of PDD for the number of joints affected was 0.7% (95% CI: 0.005 to 0.008). The pooled prevalence of PDD for the number of patients was 0.9% (95% CI: 0.007 to 0.011). PDD was found to be associated with osseous changes, including changes in the morphology of the condyle, disc, and articular eminence; osseous abnormalities (erosion, osteophytes); and joint effusion. This meta-analysis showed a very low prevalence rate of PDD in TMD patients. The limited literature did not allow conclusions to be drawn about the PDD-related features.

Journal of Oral & Facial Pain and Headache


Educational effects using a robot patient simulation system for development of clinical attitude

The aim of this study was to assess the effectiveness of improving the attitude of dental students towards the use of a full-body patient simulation system (SIMROID) compared to the traditional mannequin (CLINSIM) for dental clinical education. The participants were 10 male undergraduate dental students who had finished clinical training in the university hospital 1 year before this study started. They performed a crown preparation on an upper pre-molar tooth using SIMROID and CLINSIM as the practical clinical trials. The elapsed time for preparation was recorded. The taper of the abutment teeth was measured using a 3-dimensional shape-measuring device after this trial. In addition, a self-reported questionnaire was collected that included physical pain, treatment safety and maintaining a clean area for each simulator. Qualitative data analysis of a free format report about SIMROID was performed using text mining analysis. This trial was performed twice at 1-month intervals. The students considered physical pain, treatment safety and a clean area for SIMROID significantly better than that for CLINSIM (P < .01). The elapsed time of preparation in the second practical clinical trial was significantly lower than in the first for SIMROID and CLINSIM (P < .01). However, there were no significant differences between the abutment tapers for both systems. For the text mining analysis, most of the students wrote that SIMROID was similar to real patients. The use of SIMROID was proven to be effective in improving the attitude of students towards patients, thereby giving importance to considerations for actual patients during dental treatment.


Radiographic investigation of the marginal bone loss on dental implants, a retrospective cohort study

Background: During functional loading, the design of the dental implant may have an effect on the response of marginal bone.
Objectives: The purpose of this study was to report the prevalence of peri-implantitis, and to compare radiographic parameters around Brånemark and Replace Select dental implants and evaluate whether disparities in the morphologic features of these two indistinct implant systems, particularly their abutment-implant attachment, had an influence on the health of surrounding tissues and marginal bone loss (MBL).
Materials and Methods: Collection of data was done at the Department of Fixed Prosthodontics, the Department of Maxillo-Facial Prosthodontics, and Oral Implant Center of Tokushima University Hospital, in Tokushima, Japan; between March 2003 and followed until January 2017. Patients who have been treated with the Replace Select internal type implant and the Brånemark variety were selected as cohort. Marginal bone level measurements were evaluated via periapical and panoramic radiographs taken at regular follow-up visit. These dimensions were calculated, starting from the orientation mark at the implant abutment interface to the bottommost perceived contact area of marginal bone with the aforementioned implant system. The change in the level of bone was estimated by calculating the variation involving an initial reference value and the follow-up values.
Results: An average loss of bone at 0.65 ± 1.51 mm (range 0.36 to 7.89 mm) in the Replace Select group was observed, while in the Brånemark group 0.7 ± 1.32 mm (range 0.62 to 8.64 mm) was observed. Spearman rank correlation exhibited a statistically significant positive correlation between progress of bone loss around implant body and interval from implantation in the Brånemark group, whereas in the Replace Select group it was not significant. The Brånemark group exhibited significant (P = 0.0269) negative correlation of MBL and its diameters, whereas the Replace Select group did not exhibit such correlation.
Conclusion: Within the limits of this study, it can be concluded that deviations in the morphologic attributes of these two diverse implant systems had an influence on the health of surrounding tissues and MBL. The Brånemark implants showed a significant increase in MBL (> 1.8mm) as the time of placement elapses. This marked MBL was greater in females than males, in posterior than in anterior, and in the narrow platform implants than the regular platform implants or the wide platform implants. On the other hand, results suggested that this bone loss was greater in the mandible than the maxilla, in single-unit implant crowns than multiple implant restorations in the Replace Select group.

Background: During functional loading, the design of the dental implant may have an effect on the response of marginal bone.Objectives: The purpose of this study was to report the prevalence of peri-implantitis, and to compare radiographic parameters around Brånemark and Replace Select dental implants and evaluate whether disparities in the morphologic features of these two indistinct implant systems, particularly their abutment-implant attachment, had an influence on the health of surrounding tissues and marginal bone loss (MBL).Materials and Methods: Collection of data was done at the Department of Fixed Prosthodontics, the Department of Maxillo-Facial Prosthodontics, and Oral Implant Center of Tokushima University Hospital, in Tokushima, Japan; between March 2003 and followed until January 2017. Patients who have been treated with the Replace Select internal type implant and the Brånemark variety were selected as cohort. Marginal bone level measurements were evaluated via periapical and panoramic radiographs taken at regular follow-up visit. These dimensions were calculated, starting from the orientation mark at the implant abutment interface to the bottommost perceived contact area of marginal bone with the aforementioned implant system. The change in the level of bone was estimated by calculating the variation involving an initial reference value and the follow-up values.Results: An average loss of bone at 0.65 ± 1.51 mm (range 0.36 to 7.89 mm) in the Replace Select group was observed, while in the Brånemark group 0.7 ± 1.32 mm (range 0.62 to 8.64 mm) was observed. Spearman rank correlation exhibited a statistically significant positive correlation between progress of bone loss around implant body and interval from implantation in the Brånemark group, whereas in the Replace Select group it was not significant. The Brånemark group exhibited significant (P = 0.0269) negative correlation of MBL and its diameters, whereas the Replace Select group did not exhibit such correlation.Conclusion: Within the limits of this study, it can be concluded that deviations in the morphologic attributes of these two diverse implant systems had an influence on the health of surrounding tissues and MBL. The Brånemark implants showed a significant increase in MBL (> 1.8mm) as the time of placement elapses. This marked MBL was greater in females than males, in posterior than in anterior, and in the narrow platform implants than the regular platform implants or the wide platform implants. On the other hand, results suggested that this bone loss was greater in the mandible than the maxilla, in single-unit implant crowns than multiple implant restorations in the Replace Select group.


An investigation of the Filipino dental students' personality types

Philippine Journal of Health Research and Development


Organizational dilemma: Dental faculty acquisition in the Philippines


Technology acceptance model in the use of a patient management software in a dental school in the Philippines

IOSR Journal of Dental and Medical Sciences


A Philippine rural schools organizational climate, teachers performance, and management competencies

International Journal of Research -GRANTHAALAYAH


Filipino teachers sense of efficacy inclusion classes


Validity of peer evaluation for team-based learning in a dental school in Japan

The aim of this study was to determine the validity of peer evaluation for team-based learning (TBL) classes in dental education in comparison with the term-end examination records and TBL class scores. Examination and TBL class records of 256 third- and fourth-year dental students in six fixed prosthodontics courses from 2013 to 2015 in one dental school in Japan were investigated. Results of the term-end examination during those courses, individual readiness assurance test (IRAT), group readiness assurance test (GRAT), group assignment projects (GAP), and peer evaluation of group members in TBL classes were collected. Significant positive correlations were found between all combinations of peer evaluation, IRAT, and term-end examination. Individual scores also showed a positive correlation with group score (total of GRAT and GAP). From the investigation of the correlations in the six courses, significant positive correlations between peer evaluation and individual score were found in four of the six courses. In this study, peer evaluation seemed to be a valid index for learning performance in TBL classes. To verify the effectiveness of peer evaluation, all students have to realize the significance of scoring the team member's performance. Clear criteria and detailed instruction for appropriate evaluation are also required.


Frequency of congenitally missing permanent teeth at a primary dental care clinic in Tokushima, Japan

The Journal of Japan Association of Oral Rehabilitation


Effects of Custom-made Mouthguard Use on Physical Performance and Concentration

The International Journal of Sports Dentistry


Complications causing patients to discontinue using oral appliances for treatment of obstructive sleep apnea

Oral appliances (OAs) are commonly used as a noninvasive treatment for obstructive sleep apnea syndrome (OSAS). These devices are worn during sleep and create mandibular anterior traction to enlarge the upper airway. Continuous use of the device is essential for the success of OA therapy, but some patients stop using the OA for various reasons. The purpose of this research was to investigate complications in OA therapy that might prevent continuous use of these devices. The progress of 90 OSAS patients who visited Tokushima University Hospital and underwent OA therapy was investigated with a mailed questionnaire. All patients had been receiving OA therapy for more than 12 months. Forty patients responded to the questionnaire and of these, 22 were not wearing their OA during sleep. The average period before stopping OA therapy was 9.6 months. Answers from 38 patients who were treated with two-piece Herbst(®)-type oral appliances were analyzed. The main reasons for stopping OA therapy were: (1) it was bothersome to use; and (2) it did not effectively prevent sleep apnea. Comparison of OA complications between current OA users and nonusers revealed significant differences for the items "difficulty sleeping" and "stifling feeling". OA users recorded better scores for sleep quality than nonusers. The results of this study indicate that patients discontinued OA therapy because the appliance was "bothersome to use" and because it had "little or no effect" rather than because they experienced the typical complications of OA therapy.


Comparison between flipped classroom and team-based learning in fixed prosthodontic education


Reliability and validity of the patient disability-oriented diagnostic nomenclature system for prosthetic dentistry

The Japan Prosthodontic Society (JPS) has proposed a new diagnostic nomenclature system (DNS), based on pathogenesis and etiology, to facilitate and improve prosthodontic treatment. This system specifies patient disability and the causative factor (i.e. "B (disability) caused by A (causative factor)"). The purpose of this study was to examine the reliability and validity of this DNS. The JPS Clinical Guideline Committee assessed mock patient charts and formulated disease names using the new DNS. Fifty validators, comprising prosthodontic specialists and dental residents, made diagnoses using the same patient charts. Reliability was evaluated as the consistency of the disease names among the validators, and validity was evaluated using the concordance rate of the disease names with the reference disease names. Krippendorff's α was 0.378 among all validators, 0.370 among prosthodontic specialists, and 0.401 among dental hospital residents. Krippendorff's α for 10 validators (3 specialists and 7 residents) with higher concordance rates was 0.524. Two validators (1 specialist and 1 resident) with the highest concordance rates had a Krippendorff's α of 0.648. Common disease names had higher concordance rates, while uncommon disease names showed lower concordance rates. These rates did not show correlation with clinical experience of the validator or time taken to devise the disease name. High reliability was not found among all validators; however, validators with higher concordance rates showed better reliability. Furthermore, common disease names had higher concordance rates. These findings indicate that the new DNS for prosthodontic dentistry exhibits clinically acceptable reliability and validity.


Mandibular movement during sleep bruxism associated with current tooth attrition

Observation of attrition patterns suggests that mandibular movement in sleep bruxism (SB) may be associated with current tooth attrition. The aim of this study was to confirm this phenomenon by investigating mandibular movement and masseter muscle activity. The subject was a healthy 21-year-old Japanese male. We recorded biological signals including mandibular movement and masseter electromyograms (EMGs) with a polysomnograph. Based on the EMG using Okura's criteria, SB events were classified into clenching, grinding and mixed types according to mandibular movement criteria. The close-open mandibular movement cycles (CO-cycles) during grinding and mixed type events were selected based on mandibular movement trajectories. Fifty-eight CO-cycles were selected in seven grinding and three mixed types. We found that SB mandibular movements associated with current tooth attrition. Excessive lateral movements (ELM) beyond the canine edge-to-edge position were observed in the closing (10.3%) and opening (13.8%) phases of the CO-cycle. Total masseter muscle activity was significantly higher during voluntary grinding (VGR) than during CO-cycle including ELM (working side: P=0.036, balancing side: P=0.025). However, in the middle and late parts of the opening phase, working side masseter muscle activity was significantly higher during CO-cycle including ELM than during VGR (P=0.012). In the early part of the closing phase, balancing side masseter muscle activity was significantly higher during CO-cycle including ELM than during VGR (P=0.017). These findings suggest that excessive forceful grinding during ongoing SB events may have caused canine attrition in this patient.


Investigation of Effect on Physical Performance and Concentration by Custom-made Mouthguard Use

International Journal of Sports Dentistry


Glossopharyngeal Neuralgia Caused by Diabetes Mellitus

糖尿病神経障害と診断された舌咽神経痛の一症例


Preliminary study of neural excitation with positron emission tomography after tooth mechanical stimulation

Dentists often cannot objectively find abnormalities in patients who complain of discomfort or abnormal sensation in their dental occlusion. We hypothesized that abnormal neural transmission from the tooth is related to this occlusal discomfort sensation. Chronic tooth contact habits may induce neural excitation from the tooth to the central nervous system, and may aggravate the sensation of discomfort in the central nervous system. However, the details of neural transmission from the tooth to the central nervous system are still unclear. In this study, we stimulated a rat premolar mechanically and observed activated bran sites using positron emission tomography (PET) and 18F-2-fluoro-2-deoxy-D-glucose (FDG). We anesthetized 5-7-week-old male rats using isoflurane inhalation anesthesia and stimulated the upper right premolar mechanically with an electric von Frey system (Model 1601C, IITC Instruments) by measuring mechanical pressure. Before the tooth mechanical stimulation, we injected FDG through the rat's caudal vein and then used a stimulation intensity of 100, 200 or 300 g. We recorded FDG accumulation with PET. The PET brain images were separated into four parts (right higher, left higher, right lower and left lower) for analysis and the peak value of striatal uptake (SUV) in each part was analyzed. The PET images showed that the accumulated FDG in the right lower part of the brain was higher with 300 g tooth stimulation than with 100 or 200 g. The data showed that the tooth stimulation site in the lower part of the brain was activated with tooth stimulation by comparing it with the other parts. We also measured SUV in the right and left sensory areas, motor area, hippocampus, trigeminal ganglia (TG) and spinal cord. The TG and sensory area showed more FDG accumulation compared with mouth opening.


Relationship between the mandibular movements and deformation of the coronoid process and the condyle


睡眠時ブラキシズムの基礎と最新の捉え方

睡眠時ブラキシズムの基礎と最新の捉え方


Japan Prosthodontic Society position paper on occlusal discomfort syndrome

Dentists may encounter patients who present with a sense of a malocclusion but in whom no objective findings can be detected. For the patient who insists that there is occlusal discomfort, in the absence of evidence some dentists elect to perform an occlusal adjustment that not only fails to alleviate symptoms, and may, in fact, exacerbate the discomfort. The patient-dentist relationship is then likely compromised because of a lack of trust. In 2011, the Clinical Practice Guidelines Committee of the Japan Prosthodontic Society formulated guidelines for the management of occlusal discomfort. When formulating clinical practice guidelines, the committee bases their recommendations on information derived from scientific evidence. For "occlusal dysesthesia," however, there are an insufficient number of high-quality papers related to the subject. Therefore, a consensus meeting was convened by the Japan Prosthodontic Society to examine evidence in the Japanese- and English-language literature and generate a multi-center survey to create an appropriate appellation for this condition. As a result of the consensus meeting and survey findings, this condition may be justifiably termed "occlusal discomfort syndrome." The Japan Prosthodontics Society believes that identification of an umbrella term for occlusal discomfort might serve as a useful guide to formulating clinical practice guidelines in the future. This position paper represents summary findings in the literature combined with the results of a multicenter survey focused on dental occlusal treatment and the condition of patients who present with occlusal discomfort syndrome.


Allergic contact dermatitis caused by titanium screws and dental implants

Titanium has been considered to be a non-allergenic material. However, several studies have reported cases of metal allergy caused by titanium-containing materials. We describe a 69-year-old male for whom significant pathologic findings around dental implants had never been observed. He exhibited allergic symptoms (eczema) after orthopedic surgery. The titanium screws used in the orthopedic surgery that he underwent were removed 1 year later, but the eczema remained. After removal of dental implants, the eczema disappeared completely. Titanium is used not only for medical applications such as plastic surgery and/or dental implants, but also for paints, white pigments, photocatalysts, and various types of everyday goods. Most of the usage of titanium is in the form of titanium dioxide. This rapid expansion of titanium-containing products has increased percutaneous and permucosal exposure of titanium to the population. In general, allergic risk of titanium material is smaller than that of other metal materials. However, we suggest that pre-implant patients should be asked about a history of hypersensitivity reactions to metals, and patch testing should be recommended to patients who have experienced such reactions.


下顎大臼歯欠損に対しインプラント支持固定性補綴装置による治療介入時に付与すべき咬合様式

Clinical guidelines or definitive criteria for "Occlusal consideration for fixed implant prosthesis in mandibular posterior region" have not been established yet although the dental implant is an essential treatment option for current prosthetic dentistry. This position paper aimed to propose a critical recommendation and consequently indicate a tentative practice guideline. In this paper, the first and second molar missing in the mandible was assumed as the most typical partial edentulous jaw. A panel of clinical experts concerning dental implant practice was selected from the members of the Japan Prosthodontic Society, and a meeting was held to collect clinical data obtained from daily practice and to estimate expert opinions. As a result, general remarks were presented regarding shapes of prostheses, position and number of occlusal contact points, occlusal contact during lateral excursion, displacement of periodontal ligament, and materials of occlusal surface. However, the expert opinions described above have not been supported by clinical evidence. Moreover, neither the effect of those therapies nor long-term prognosis has been thoroughly investigated. Thus, further study for collecting the clinical evidences is required to formulate the clinical guideline.

インプラント治療が補綴歯科臨床の場で必要不可欠となった今日においても，未だ「インプラント支持固定性補綴装置に付与すべき咬合様式」のガイドラインまたは明確な基準は示されていない．本ポジションペーパーにおいては，その推奨されるべき一定の基準を示し，臨床上の指針として提案することを目的とした．本稿では，典型的な欠損形態である下顎大臼歯部欠損にインプラント支持補綴装置を装着した場合を想定している．口腔インプラントを適用した治療に関して経験豊富なエキスパートパネルを，(公社)日本補綴歯科学会会員から選出し，臨床の現場における事象を検証した結果として得られた意見を集積し，パネル会議で検討した．その結果，補綴装置の形態，咬合接触点の位置と数，側方運動時の咬合接触の有無，歯根膜の変位量の考慮，補綴装置咬合面の材料等に関する知見が得られ，推奨される一定の基準が示された．しかしながら，上記内容は明確な根拠に支持されるものではなく，治療効果と術後経過に関する研究が不十分であり，今後さらなる知見の集積と検証のもとに，ガイドラインを策定すべきである．


Sleep bruxism frequency and platelet serotonin transporter activities in young adult subjects

To evaluate correlations between serotonin transporter (SERT) uptake ability in human peripheral platelets and sleep bruxism (SB) frequency. Subjects were consecutively recruited from sixth-year students at Okayama University Dental School. Subjects were excluded if they (1) were receiving orthodontic treatment, (2) had a dermatological disease, (3) had taken an antidepressant within 6 months, or (4) had used an oral appliance within 6 months. SB frequency was determined as the summary score of three consecutive night assessments using a self-contained electromyography detector/analyzer in their home. Fasting peripheral venous blood samples were collected in the morning following the final SB assessment. SERT amount and platelet number were quantified via an ELISA assay and flow cytometry, respectively. Functional SERT characterization, 5-hydroxytryptamine (5-HT) uptake, maximum velocity (V max), and an affinity constant (K m ) were assessed with a [(3)H] 5-HT uptake assay. The correlations between these variables and SB level were evaluated. Among 50 eligible subjects (26 males, mean age 25.4 ± 2.41 years), 7 were excluded because of venipuncture failure, smoking, and alcohol intake during the experimental period. A small but significant negative correlation between SB level and [(3)H] 5-HT uptake was observed (Spearman's correlation R (2) = 0.063, p = 0.04). However, there were no significant correlations between SB level and total platelet amount, SERT, V max, and K m values (p = 0.08, 0.12, 0.71, and 0.68, respectively). Platelet serotonin uptake is significantly associated with SB frequency, yet only explains a small amount of SB variability.


根尖性歯周炎に起因した放射線性下顎骨骨髄炎に対して保存的治療を行い良好な経過を得た一症例

The Japanese Journal of Conservative Dentistry


Masticatory performance alters stress relief effect of gum chewing

We evaluated the effects of gum chewing on the response to psychological stress induced by a calculation task and investigated the relationship between this response and masticatory performance. Nineteen healthy adult volunteers without dental problems undertook the Uchida-Kraepelin (UK) test (30min of reiterating additions of one-digit numbers). Before and immediately after the test, saliva samples were collected from the sublingual area of the participants. Three min after the UK test, the participants were made to chew flavorless gum for 3min, and the final saliva samples were collected 10min after the UK test. The experiment was performed without gum chewing on a different day. Masticatory performance was evaluated using color-changing chewing gum. Salivary CgA levels at immediately and 10min after the UK test were compared with and without gum chewing condition. Two-way repeated measures analysis of variance revealed significant interaction between gum chewing condition and changes in CgA levels during post 10min UK test period. A significant correlation was found between changes in CgA levels and masticatory performance in all participants. Our results indicate that gum chewing may relieve stress responses; however, high masticatory performance is required to achieve this effect.


Cross-excitation in peripheral sensory ganglia is associated with pain transmission

Despite the absence of synaptic contacts, cross-excitation of neurons in sensory ganglia during signal transmission is considered to be chemically mediated and appears increased in chronic pain states. In this study, we modulated neurotransmitter release in sensory neurons by direct application of type A botulinum neurotoxin (BoNT/A) to sensory ganglia in an animal model of neuropathic pain and evaluated the effect of this treatment on nocifensive. Unilateral sciatic nerve entrapment (SNE) reduced the ipsilateral hindpaw withdrawal threshold to mechanical stimulation and reduced hindpaw withdrawal latency to thermal stimulation. Direct application of BoNT/A to the ipsilateral L4 dorsal root ganglion (DRG) was localized in the cell bodies of the DRG and reversed the SNE-induced decreases in withdrawal thresholds within 2 days of BoNT/A administration. Results from this study suggest that neurotransmitter release within sensory ganglia is involved in the regulation of pain-related signal transmission.


A preliminary investigation of reproducibility of EMG signals during daytime masticatory muscle activity using a portable EMG logging device

Journal of Electromyography and Kinesiology


A longitudinal retrospective study of the analysis of the risk factors of implant failure by the application of generalized estimating equations

Many studies have identified risk factors for dental implant failure, although few have investigated the correlation among implant fixtures within single patients. A better analytical method may include repeated measures analysis including generalized estimating equations (GEE). This retrospective cohort study aimed to (1) identify the risk factors for failure of dental implantation and (2) evaluate an analytical method using GEE analysis. We analyzed data on early and late implant failures in 296 patients providing 721 rough surface dental implants (2.44 implants per patient). Potential predictors of implant failure included age, gender, smoking, location of implant, use of bone augmentation, number of remaining teeth, opposing tooth condition, fixture length, fixture diameter and type of suprastructure (fixed or removable partial denture). The likelihood of early and late implant failure was estimated by GEE. The early failure rate was 1.5% (11/721 implants, 7/296 patients) and the 10-year cumulative survival rate was 94.0% (7/710 implants, 5/293 patients). The GEE analysis revealed that a significant risk factor for early implant failure was smoking (p<0.01), whereas significant risk factors for late failure were maxillary implant (p=0.02), posterior implant (p<0.01), number of remaining teeth (≥20) (p<0.01), opposing unit being a removable partial denture or nothing (p=0.04) and having a removable type suprastructure (p<0.01). GEE analysis showed that smoking was a risk factor for early implant failure, and several risk factors were identified for late implant failure.


Diagnosis and treatment for obstructive sleep apnea: Fundamental and clinical knowledge in obstructive sleep apnea

This review article covers the diagnosis and treatment of obstructive sleep apnea (OSA) from a dental perspective. It addresses the issue of when and how to screen for and then, if indicated, refer the patient for a more comprehensive. Our focus in this article was on identifying current unanswered questions that relevant to OSA problems that dental scientists have to pursue and on providing valuable information on that problems, consequently the previous studies which investigated or reviewed the diagnosis and treatment of OSA were included. In addition, we included studies on jaw movements during sleep and on the use of a lateral cephalometric film related to the diagnosis and treatment of OSA. The role of portable sleep monitoring devices versus full laboratory polysomnography is discussed. This review also describes what is known about the efficacy of mandibular advancement devices and when and how they fit in to a treatment program for a patient with obstructive sleep apnea. Finally some basic research is presented on jaw movements during sleep and how a lateral cephalometric film can be used to assess the changes of the airway with body posture and head posture. This article provides the valuable suggestions for the clinical questions in the diagnosis and treatment of OSA.


Effects of team-based learning on fixed prosthodontic education in Japan

The aims of this study were to evaluate the quality of team-based learning (TBL) in prosthodontics education for fourth-year dental students at Tokushima University School of Dentistry and to compare this teaching method with traditional lecture-based delivery. Participants in the study were 36 students (22 males and 14 females) who attended the TBL-style fixed prosthodontics course. Ten 60-minute classes were held. The first three were traditional lecture-style classes and were followed by one class introducing the TBL style. The remaining six classes constituted the TBL-format fixed prosthodontics course. The effectiveness of TBL was evaluated through student questionnaires at the end of each class and the results of the term-end examination. The questionnaire revealed high student approval for TBL-style learning, and active group discussion among students during TBL was a key factor in these ratings. In the results of the term-end examination, there were significantly higher scores on the questions that covered TBL-taught material than those covering traditional lecture-taught topics. The results of this study suggest that TBL-style lecture was more effective than traditional-style lecture for teaching fixed prosthodontics and that TBL was a more efficient mode of delivering dental education than traditional lecture-based teaching.


Introduction and Effects of Team-Based Learning on Prosthodontic Education

歯科補綴学授業におけるTeam-Based Learningの導入とその効果

Team-Based Learning (TBL) was introduced into our prosthodontic education for thirdyear dental school students. Forty students (26 males and 14 females) of Tokushima University School of Dentistry attended the TBL-style fixed prosthodontic course. A total of fifteen classes (60 minutes each), which started with six conventional lecture-style classes followed by 8 TBL-style classes, were held. The effectiveness of TBL was evaluated with student questionnaires at the end of each class and with the results of the term-end examination. The results of the questionnaire on some questions and term-end examination exhibited higher score for the TBL. The results of this study showed that TBL-style classes were more effective than that of the conventional lecture-style classes for the fixed prosthodontic course.


Basic research and clinical investigations of the neural basis of orofacial pain


Establishment of a method for measuring and analyzing various bio-information during a sequence of feeding : Development of a measuring system

摂食・咀嚼・嚥下過程における各種生体情報の記録解析法の開発 ―測定システムの開発―

The Journal of Japan Association of Oral Rehabilitation

日本口腔リハビリテーション学会雑誌


Development of a new method for understanding visually slight tooth movements with six-degree-of-freedom

歯の6自由度運動を視覚的に理解する手法の開発

日本口腔リハビリテーション学会雑誌


咬合違和感を訴える患者の実態に関する多施設実態調査

咬合違和感を訴える患者の実態に関する多施設実態調査

Journal of the Japanese Society for the Temporomandibular Joint


A proposed core curriculum for dental English education in Japan.

Globalization of the professions has become a necessity among schools and universities across the world. It has affected the medical and dental professions in terms of curriculum design and student and patient needs. In Japan, where medicine and dentistry are taught mainly in the Japanese language, profession-based courses in English, known as Medical English and Dental English, have been integrated into the existing curriculum among its 83 medical and 29 dental schools. Unfortunately, there is neither a core curriculum nor a model syllabus for these courses. This report is based on a survey, two discussion forums, a workshop, and finally, the drafting of a proposed core curriculum for dental English approved by consensus of the participants from each university. The core curriculum covers the theoretical aspects, including dental English terms and oral pathologies; and practical aspects, including blended learning and dentist-patient communication. It is divided into modules and is recommended to be offered for at least two semesters. The core curriculum is expected to guide curriculum developers in schools where dental English courses are yet to be offered or are still in their early development. It may also serve as a model curriculum to medical and dental schools in countries in Asia, Europe, Africa, and Central and South America, where English is not the medium of instruction.


Systematic review and recommendations for nonodontogenic toothache

Nonodontogenic toothache is a painful condition that occurs in the absence of a clinically evident cause in the teeth or periodontal tissues. The purpose of this review is to improve the accuracy of diagnosis and the quality of dental treatment regarding nonodontogenic toothache. Electronic databases were searched to gather scientific evidence regarding related primary disorders and the management of nonodontogenic toothache. We evaluated the level of available evidence in scientific literature. There are a number of possible causes of nonodontogenic toothache and they should be treated. Nonodontogenic toothache can be categorised into eight groups according to primary disorders as follows: 1) myofascial pain referred to tooth/teeth, 2) neuropathic toothache, 3) idiopathic toothache, 4) neurovascular toothache, 5) sinus pain referred to tooth/teeth, 6) cardiac pain referred to tooth/teeth, 7) psychogenic toothache or toothache of psychosocial origin and 8) toothache caused by various other disorders. We concluded that unnecessary dental treatment should be avoided.


Comparison of platelet serotonin transporter activity in subjects with severe sleep bruxism and control

The aim of this study was to evaluate the correlation between sleep bruxism (SB) frequency and serotonin transporter (SERT)-driven serotonin (5-HT)-uptake in platelets. Subjects were dental trainee residents and faculty members of Okayama University Hospital who were aware of having severe or no SB. SB frequency was assessed for 3-consecutive nights by a self-contained electromyographic detector/analyzer, which indicated individual SB levels as one of four grades (score 0, 1, 2 and 3). Subjects were classified as normal control (NC) when SB scores indicated only 0 or 1 during the 3 nights, or as severe SB for scores 2 or 3. Those subjects whose scores fluctuated from 0 to 3 during the 3 nights were omitted from further analysis. Fasting peripheral venous blood samples were collected in the morning following the final SB assessment. Amounts of SERTs proteins collected from peripheral platelets were quantified using ELISA, and SERTs transport activity was assessed by uptake assay using [(3)H]-5-HT. Thirteen severe SB subjects and 7 NC subjects were eligible. Gender distribution, mean age, 5-HT concentration and total amounts of SERT protein in platelets showed no significant differences between NC and severe SB (p=0.85: Chi-squared test; p=0.64, 0.26, 0.46: t-test). However, [(3)H]-5-HT uptake by platelets was significantly greater in NC compared to severe SB subjects (12.79±1.97, 8.27±1.91fmol/10(5) platelets/min, p<0.001, t-test). The results of this pilot study suggest a possible correlation between peripheral platelet serotonin transporter uptake ability and SB severity.


Effect of an exclusion range of jaw movement data from the intercuspal position on the estimation of the kinematic axis point

In patients who have lost natural occlusal contacts, the centric relation is usually estimated based on several anatomical factors such as the temporomandibular joint and masticatory muscles except dental arch. The clinical procedure to record the centric relation often depends on the clinician's expertise and technique; an objective method to determine proper occlusal position is desirable. The kinematic axis point (KAP) is kinematically estimated from sagittal movements and is an ideal posterior reference point that is used in dental articulators for reproducing jaw movement. Occlusal registration using the KAP may serve as a definite objective technique. The aim of this study is to investigate the effect of the exclusion range of sagittal jaw movement data from the intercuspal position (ICP) on the estimation of the KAP. The complete and incomplete sagittal border movement data of dentate subjects were used to estimate the KAPs. The locations of the estimated KAPs were compared. The results indicate that the incomplete sagittal border jaw movement data set does not include data points inside a 7mm distance from the ICP can be used for estimation of the KAP. In conclusion, the sagittal border jaw movement data around the ICP is not indispensable in the valid identification of the KAP.


Case report of recurrent temporomandibular joint open lock associated with abrupt reduction of displaced articular disk

This report describes the case of a 51-year-old male patient who initially presented at age 23 with a habitual intermittent open lock (at >35mm) in the left temporomandibular joint (TMJ). The patient was able to manage this affliction through rapid-repetition jaw opening and closing. Tomography of the joint showed no irregular morphology, but intraoral examination revealed an occlusal interference at the mandibular left third molar during leftwards excursion. For this patient, alteration of lateral guidance using a palatal plate attached to the maxillary left canine precluded this intermittent open lock, but at 22 years of age, the open lock recurred and could not be relieved by the patient, who was unable to assume an occlusal position. Because conservative treatment was ineffective, a pumping manipulation technique was applied to reduce the open lock, after which the patient has maintained good jaw function. MRI taken before and after repositioning indicated that abrupt reduction of a displaced articular disk was the cause of the open lock, and that this articular disk was restored to its proper position during the manipulation. Most TMJ open locks occur as anterior dislocation, where the mandibular head becomes trapped anterior to the articular eminences, causing excessive opening and difficulty closing. Our clinical findings from this patient indicate that open lock can occur through abrupt reduction of a displaced articular disk, particularly in patients with chronic internal derangement of the TMJ. TMJ open lock can occur following abrupt reduction of a displaced articular disk.


Clinical application of removable partial dentures using thermoplastic resin Part II: Material properties and clinical features of non-metal clasp dentures

This position paper reviews physical and mechanical properties of thermoplastic resin used for non-metal clasp dentures, and describes feature of each thermoplastic resin in clinical application of non-metal clasp dentures and complications based on clinical experience of expert panels. Since products of thermoplastic resin have great variability in physical and mechanical properties, clinicians should utilize them with careful consideration of the specific properties of each product. In general, thermoplastic resin has lower color-stability and higher risk for fracture than polymethyl methacrylate. Additionally, the surface of thermoplastic resin becomes roughened more easily than polymethyl methacrylate. Studies related to material properties of thermoplastic resin, treatment efficacy and follow-up are insufficient to provide definitive conclusions at this time. Therefore, this position paper should be revised based on future studies and a clinical guideline should be provided.


Clinical application of removable partial dentures using thermoplastic resin-Part I: Definition and indication of non-metal clasp dentures

This position paper proposes a definition and naming standard for removable partial dentures (RPDs) using thermoplastic resin, and presents a guideline for clinical application. A panel of 14 experts having broad experience with clinical application of RPDs using thermoplastic resin was selected from members of the Japan Prosthodontic Society. At a meeting of the panel, "non-metal clasp denture" was referred as the generic name of RPDs with retentive elements (resin clasps) made of thermoplastic resin. The panel classified non-metal clasp dentures into two types: one with a flexible structure that lacks a metal framework and the other having a rigid structure that includes a metal framework. According to current prosthetic principles, flexible non-metal clasp dentures are not recommended as definitive dentures, except for limited cases such as patients with a metal allergy. Rigid non-metal clasp dentures are recommended in cases where patients will not accept metal clasps for esthetic reasons. Non-metal clasp dentures should follow the same design principles as conventional RPDs using metal clasps.


Potential Risk of Metal Allergy Associated with Pierced Earrings Containing Nickel

ニッケル含有ピアスによる金属アレルギー発症の危険性について

Journal of Environmental Dermatology and Cutaneous Allergology

日本皮膚アレルギー・接触皮膚炎学会雑誌


Mandibular Movement during Sleep Bruxism: Mandibular Position with Peak Masseter Muscle Activity

The Journal of Japan Association of Oral Rehabilitation


Retrospective investigation of the remaining teeth status of patients with implant-supported fixed partial dentures in unilateral free-end edentulism

This study aimed to compare the various complication-free rates and survival rates of remaining teeth among implant-supported fixed dentures (IFDs), removable partial dentures (RPDs) and no-restoration (NR) patients with unilateral free-end edentulism. The study subjects were selected among those who received prosthodontic treatment at Okayama University Dental Hospital for their unilateral free-end edentulism (2 or 3 missing teeth). Thirty-three patients were included in the IFD group, 41 matched patients in the RPD group, and 10 patients who received RPDs but refused their use were regarded as NR group. The remaining dentition was classified into five subcategories in relation to the missing portion: adjacent teeth to the missing portion (AD), contralateral posterior dentition in the same jaw (CS) and in the opposite jaw (CO), ipsilateral opposing posterior dentition (IO), and anterior dentition (AN). Complications were defined as tooth extraction, periodontal lesions, periapical lesions or loss of retention of the prosthesis and were assessed by one examiner based on the hospital chart records. The cumulative complication-free rates in the remaining teeth were significantly different among each of the three groups (p<0.01), with a significantly lower incidence rate in the IFD group. Regarding the cumulative survival rate of the remaining teeth, there was a significant difference only between IFD and NR group (p=0.01), especially in the CO region (p=0.04). Stable posterior occlusal support obtained with IFD treatment for unilateral free-end edentulism may reduce the incidence of complications in the remaining teeth, by decreasing the adverse mechanical stress.


熱可塑性樹脂を用いた部分床義歯 (ノンメタルクラスプデンチャー)の臨床応用

熱可塑性樹脂を用いた部分床義歯 (ノンメタルクラスプデンチャー)の臨床応用


One of the patients with difficulty, there is a case to complain of discomfort or abnormal sense of occlusion, the dentist is able to encounter patients with objective findings that can not be confirmed. Usually, although confirmation is using articulating paper, wax, and silicone materials, no abnormalities found in the state especially occlusal contact. In addition, for the insistent demand of the patient to the discomfort occlusion, the dentist may easily gone the occlusal adjustment. As a result, not only does not improve the patient's complaint, its symptoms may even also be worse in reverse. And the relationship of trust between the patient and the dentist will break. And it may even be caught in a direction unfavorable unexpected. For discomfort related to occlusion, in clinical practice guidelines committee in Japan Prostjodontic Siciety, creating clinical practice guidelines related to occlusal dysesthesia were studied.In the development of clinical practice guidelines, we have attempted to formulate guidelines created by a panel of the Commission, there are few high-quality paper sufficiently related to occlusal dysesthesia, did not lead to the creation of clinical practice guidelines. Therefore, a consensus meeting held on occlusal discomfort as Japan Prosthodontic Society, examined the appropriate designation of this disease. From the results of the pre-survey, this disease has to be called and "occlusal discomfort syndrome".For the purpose of indicating the direction of research activities and creating clinical practice guidelines in the future, the position paper of this time, a multi-center was carried out on the current situation and the course of dental treatment up to this syndrome patients uncomfortable occlusion literature and one of the few in the past was created from the findings of a patient with.

難症例の1つに咬み合わせ異常感や違和感があり，その訴えに対応する客観的所見が確認できない症例に遭遇することがある．通常，咬合紙，ワックス，シリコーンなどを用いて確認はするものの，咬合接触状態に特に異常は見つからない．さらに，患者の咬合に関する執拗な訴えに対して歯科医師が患者に問題の部位を確認してもらい，患者の指示により咬合調整を行ってしまうといった患者の感覚主導型治療に陥ってしまうことがある．その結果，患者の訴えは改善しないばかりか，逆に悪化することもさえもある．そして，患者と歯科医師の信頼関係が壊れ，思わぬ方向に陥ってしまうことも珍しくない． このような患者が訴える咬合に関する違和感に対して，社団法人日本補綴歯科学会，診療ガイドライン委員会において，平成23年度「咬合感覚異常(症)」に関する診療ガイドラインの策定が検討された．診療ガイドラインの策定に際し，委員会の作成パネルによるガイドライン策定を試みたが，咬合感覚異常(症)に関する十分に質の高い論文は少なく，診療ガイドラインの作成には至らなかった．そこで，本委員会のパネルで協議した結果，「咬合感覚異常(症)」に対する日本補綴歯科学会としてのコンセンサス・ミーティングを開催して本疾患の適切な呼称の検討を行った．また事前のアンケート調査結果から，このような病態を「咬合違和感症候群(occlusal discomfort syndrome)」とした． 今回のポジションペーパーは，今後の診療ガイドラインの作成とそれに対する研究活動の方向性を示す目的で，過去の文献と咬合違和感症候群患者のこれまでの歯科治療の経過や現在の状況について実施した多施設による患者の調査結果をもとに作成された．


Primary treatment of temporomandibular disorders: The Japanese Society for the temporomandibular joint evidence-based clinical practice guidelines, 2nd edition

the Evidence-based Clinical Practice Guidelines Task Force


Reliability and validity of diagnostic nomenclature system of prosthetic dentistry

補綴歯科治療病名システムの信頼性と妥当性の検討

Purpose: The Japan Prosthodontic Society (a public interest incorporated association) proposed a new diagnostic nomenclature system method that is based on pathogenesis and etiology for providing adequate prosthodontic treatment to patients. This diagnostic nomenclature system is based on "factor" and "disability", and assumes that a disability is caused by a factor. The aim of this study was to analyze the reliability and validity of several dentists' diagnoses on mock patient charts.Methods: The Clinical Guideline Committee of the Japan Prosthodontic Society made mock patient charts and decided the disease name with the new diagnosis system. Fifty evaluators (prosthodontic specialists and hospital residents) answered the disease name with the new diagnosis system. The reliability and validity of the diagnoses were analyzed.Results: Krippendorff's α, which evaluates the reliability, was 0.378 (prosthodontic specialists) and 0.401 (hospital residents). The value was 0.524 with the top 10 evaluators, and 0.628 with the top 2 evaluators. There was no difference between the prosthodontic specialists and hospital residents in the correct answer rate. The correct answer rate for common dental diseases was high and that for uncommon dental diseases was low. Moreover, there was no relation between the correct answer rate and answering time or years of experience.Conclusion: The reliability of the answers among all evaluators was not high, but it was high among the evaluators who showed a high correct answer rate in this study. The correct answer rate for common dental diseases was high and that for uncommon dental diseases was low.

目的:(社)日本補綴歯科学会は病態とその発現機序の把握に基づく適切な補綴歯科治療を国民に提供するために，補綴歯科治療における新たな病名システムを提案した．これは患者に生じている「障害」を病名の基本とし，この障害を引き起こしている「要因」を併記して病名システムとするものであり，「A(要因)によるB(障害)」を病名システムの基本的な表現法としている．本研究の目的は考案した方法に従って決定した補綴歯科治療における病名の信頼性と妥当性を検討することである．方法:模擬患者カルテを作成し，(社)日本補綴歯科学会診療ガイドライン委員会で模範解答としての病名(以下，模範病名)を決定した．その後，合計50 名の評価者(日本補綴歯科学会専門医(以下，補綴歯科専門医)ならびに大学病院研修歯科医(以下，研修医))に診断をしてもらい，評価者間における病名の一致度(信頼性)ならびに(社)日本補綴歯科学会診療ガイドライン委員会による模範病名との一致度(妥当性)を検討した．結果:評価者間の一致度を検討するための算出したKrippendorff's αは全体では0.378，補綴歯科専門医では0.370，研修医では0.401 であった．Krippendorff's αは模範病名との一致度の高い上位10 名の評価者(補綴歯科専門医:3 名，研修医:7 名)では0.524，上位2 名の評価者(補綴歯科専門医:1 名，研修医:1 名)では0.648 と上昇した．日常的に頻繁に遭遇する病名に関しては模範病名との一致度が高かったが，日常的に遭遇しない病名は模範病名との一致度は低い状況であった．さらに，模範病名との一致度とアンケート回答時間や診療経験年数の関連性を検討したところ，相関関係はみられなかった．結論:全評価者間の一致度を指標とした本病名システムの信頼性は高くはなかったが，模範病名との一致度の高い評価者間では一致度が高かった．日常的に遭遇する補綴関連病名については模範病名との一致度が高かった．以上から(公社)日本補綴歯科学会の新しい病名システムは臨床上十分な信頼性と妥当性を有することが示唆された．


A retrospective comparative ten-year study of cumulative survival rates of remaining teeth in large edentulism treated with implant-supported fixed partial dentures or removable partial dentures

This study aimed to compare the survival rates of remaining teeth between implant-supported fixed dentures (IFDs) and removable partial dentures (RPDs) in patients with large edentulous cases. The second goal was to assess the risk factors for remaining tooth loss. The study subjects were selected among those who received prosthodontic treatment at Okayama University Dental Hospital for their edentulous space exceeding at least four continuous missing teeth. Twenty-one patients were included in the IFD group and 82 patients were included in the RPD group. Survival rates of remaining teeth were calculated in three subcategories: (1) whole remaining teeth, (2) adjacent teeth to intended edentulous space, and (3) opposing teeth to intended edentulous space. The ten-year cumulative survival rate of the whole remaining teeth was significantly higher in the IFD group (40.0%) than in the RPD group (24.4%). On the other hand, there was no significant difference between two groups in the survival rate of teeth adjacent or opposing to intended edentulous space. A Cox proportional hazard analysis revealed that RPD restoration and gender (male) were the significant risk factors for remaining tooth loss (whole remaining teeth). These results suggest that IFD treatment can reduce the incidence of remaining tooth loss in large edentulous cases.


Identification of risk factors for fracture of veneering materials and screw loosening of implant supported fixed partial dentures in partially edentulous cases

This retrospective study identified the risk factors for fracture of veneering materials and screw loosening of implant-supported fixed partial dentures in partially edentulous cases. The study group included a total of 182 patients who were installed 219 suprastructures at the Fixed Prosthodontic Clinic of Okayama University Dental Hospital between February 1990 and March 2005 and were subdivided in two subgroups: 120 patients (149 facing suprastructures) were included in the subgroup to investigate the risk factors of fracture of veneering materials, and 81 patients (92 suprastructures) were included in the subgroup to identify the risk factors of abutment screw loosening. Each patient was followed up from the day of suprastructure installation until March, 2005. A Cox proportional hazards regression model was used to identify the risk factors related to technical complications, and eight factors were regarded as candidate risk factors. Screw retention was the significant risk factor for fracture of veneering materials, whereas connection of suprastructures with natural tooth was the significant risk factor for screw loosening. It was suggested that screw retention was a significant risk factor for the fracture of veneering materials, and connection of suprastructures with natural tooth was a significant risk factor for screw loosening. Future studies, involving dynamic factors (e.g. bruxism) as predictors as well, are more helpful to discuss the risk factor of fracture of veneering materials and screw loosening.


Self-reported aural symptoms, headache and temporomandibular disorders in Japanese young adults

To investigate the associations of aural symptoms, headache and depression with the presence of temporomandibular disorder (TMD) symptoms in a young adult population in Japan. A personal interview survey was conducted on first-year university students (n = 1,930) regarding symptoms of TMD, aural problems, headache, shoulder pain and depression. Logistic regression was applied to assess the associations of these problems with the presence of TMD symptoms after controlling for age and gender. Among the 1,930 students, 543 students exhibited TMD symptoms and were classified into 7 groups: clicking only (Group I, n = 319), pain in the TMJ only (Group II, n = 21), difficulty in mouth opening only (Group III, n = 18), clicking and pain (Group IV, n = 29), clicking and difficulty in mouth opening (Group V, n = 48), difficulty in mouth opening and pain (Group VI, n = 11), and combination of three symptoms (Group VII, n = 97). The control group (n = 1,387) were subjects without any TMD symptoms. After adjusting for age and gender, a strong association was observed between TMD symptoms (Group II and IV) and tinnitus (OR = 12.1 and 13.2, respectively). TMD symptoms (Group I, II and III) were also associated with vertigo and headache. Otalgia and depression were significantly associated with the presence of clicking only. TMD symptoms were significantly correlated to aural symptoms and headache. A functional evaluation of the stomatognathic system should be considered in subjects with unexplained aural symptoms and headache.


A retrospective comparative 8-year study of cumulative complications in teeth adjacent to both natural and implant-supported fixed partial dentures

To compare the complication rate of natural teeth adjacent to implant supported dentures (IFDs) with that of teeth serving as abutments for fixed partial dentures (FPDs). The second goal was to assess the risk factors for complications in teeth adjacent to bounded edentulous spaces. The study subjects were selected from patients who received prosthodontic treatment for their bounded edentulous space not exceeding two missing teeth between February 1990 and March 2007. Sixty-one patients were included in the IFD group and 66 patients were included in the FPD group. Tooth complications were defined as tooth extraction, periodontal lesion, periapical lesion, and loss of prosthesis and were assessed by one examiner based on dental records. The 8-year cumulative complication rate for the IFD group (7.9%) was significantly lower than for the FPD group (40.7%). Additionally, the 8-year cumulative complication rate of vital teeth (6%) was significantly lower than that of nonvital teeth (45.9%). A cox proportional hazard analysis revealed that nonvitality of dental pulp was a significant risk factor for tooth complications, whereas treatment modality was not. Teeth adjacent to IFD-treated edentulous spaces presented fewer complications than natural teeth serving as abutments for FPDs. Conservation of teeth adjacent to edentulous spaces as vital teeth was the key finding to limit further tooth loss.

The International Journal of Prosthodontics


A Problem-Based Learning Tutorial for Dental Students Regarding Elderly Residents in a Nursing Home in Japan

This educational trial was an eight-day problem-based learning (PBL) course for fourth-year predoctoral students at Okayama University's dental school who interviewed elderly residents living in a nursing home. The purpose of this PBL course was to introduce geriatric dentistry to the students by allowing them, independently, to discover the clinical problems of elderly patients as well as the solutions. The sixty-five students were divided into nine small groups and received patient information (age, gender, degree of care needed, medical history, food type, medications, and oral condition) in datasheets before visiting the nursing home. Each group of students directly interviewed one patient and the caregivers and identified the patient's medical, psychological, and social problems. After the interview, the students participated in a PBL tutorial to delineate a management approach for the patient's problems. To measure the efficacy of this program, the students completed a questionnaire before and after the course regarding their level of understanding of and attitudes toward geriatric dentistry, clinical research, and self-study. The results showed that student's perceptions of their knowledge about and attitudes toward oral health care for the elderly significantly increased after the PBL course, which suggests that such tutorials should be an option for dental curricula.


主機能部位でのストッピング嚙みしめ時の顆頭運動

主機能部位でのストッピング嚙みしめ時の顆頭運動


Matrix metalloproteinase-8 is the major potential collagenase in active peri-implantitis.

PURPOSE: Current clinical procedures to control or regenerate bone loss due to peri-implantitis are not predictable neither accomplish complete resolution. Therefore, early detection of the onset and the active periods of bone loss are crucial for prevention of extensive peri-implant bone resorption. This study aimed to determine a possible association between the presence of collagenases (MMP-1, MMP-8 and MMP-13) in peri-implant sulcular fluid (PISF) and active periods of bone loss by annually adjusted vertical bone loss (AVBL) measurements. METHODS: Intended sample consisted of 76 consecutive patients who received oral implant treatment at the Fixed Prosthodontic Clinic of Okayama University Hospital from 1990 to 2000. Twelve subjects were lost to follow-up or refused to participate. Consequently, the actual sample consisted of 64 patients who were followed-up for at least one year. Those patients with AVBL>0.6mm were included in the severe peri-implantitis group, and randomly selected, age-, gender- and implantation site-matched healthy patients (AVBL<0.3mm) comprised the control group. PISF samples were collected from both groups and further analyzed by western blot for detection of collagenases. RESULTS: Four patients presented severe peri-implantitis. MMP-8 was the only collagenase detected in peri-implant sites with ongoing bone loss. PISF samples from control group showed no positive reactions to any collagenase. CONCLUSION: This study showed MMP-8 as a possible marker for progressive bone loss in peri-implantitis.


Application of Purified Botulinum Type A Neurotoxin to Treat Experimental Trigeminal Neuropathy in Rats and Patients with Urinary Incontinence and Prostatic Hyperplasia.

Type A neurotoxin (NTX) of Clostridium botulinum was purified by a simple procedure using a lactose gel column. The toxicity of this purified toxin preparation was retained for at least 1 year at -30°C by supplementation with either 0.1% albumin or 0.05% albumin plus 1% trehalose. When purified NTX was used to treat 49 patients with urinary incontinence caused by either refractory idiopathic or neurogenic detrusor overactivity, 36 patients showed significant improvement in symptoms. These beneficial effects were also observed in cases of prostatic hyperplasia. The results obtained with NTX were similar to that of Botox. The effects of NTX on trigeminal neuralgia induced by infraorbital nerve constriction (IoNC) in rats were also studied. Trigeminal ganglion neurons from ipsilateral to IoNC exhibited significantly faster onset of FM4-64 release than sham-operated contralateral neurons. Intradermal injection of NTX in the area of IoNC alleviated IoNC-induced pain behavior and reduced the exaggerated FM4-64 release in trigeminal ganglion neurons.


Occlusal dysesthesia: a qualitative systematic review of the epidemiology, aetiology and management.

Summary Occlusal dysesthesia refers to a persistent complaint of uncomfortable bite sensation with no obvious occlusal discrepancy. This systematic review aimed to draw a picture of such patients, to present an agreement of previously reported diagnostic criteria and to analyse the evidence level of the recommended management approaches. An electronic search for all relevant reports on occlusal dysesthesia was thoroughly performed based on previous nomenclatures (e.g. phantom bite, occlusal hyperawareness) in PubMed and The Cochrane Library in July, 2011. A total of 84 reports were matched, among which only 11 studies were included after a two-step (abstract and detailed full-text revision) screening process. Additionally, a thorough manual review of reference lists of the included reports enabled the inclusion of two additional studies. Data analysis revealed that 37 occlusal dysesthesia patients presented a mean age of 51·7 ± 10·6 years and were predominantly women (male/female: 1/5·1) with symptom duration of more than 6 years (average: 6·3 ± 7·5 years) and with concomitant psychological disturbances (e.g. mood disorders, somatoform disorders, personality disorders). Only four authors presented diagnostic criteria for occlusal dysesthesia, which served as the basis for an agreement in the diagnostic criteria. Treatment approaches included psychotherapy, cognitive/behaviour therapy, splint therapy and prescription of anti-depressants or anti-anxiety drugs. Classification of evidence level of management approaches, however, revealed that most of them were expert opinions with single- or multiple-case report(s). Future studies are necessary for a deeper understanding of the mechanisms behind the occlusal dysesthesia symptoms, and consequently, for improvements in evidence-based management approaches.


Multiple sleep bruxism data collected using a self-contained EMG detector/analyzer system in asymptomatic healthy subjects.

PURPOSE: Small, self-contained electromyographic (EMG) detector/analyzer (D/A) devices have become available for the detection of jaw muscle activity events above threshold. These devices claim to be less intrusive to the subjects sleep so it is less prone to induce disturbed sleep. The objective of this study was to evaluate for night-to-night variability and examine for a systematic alteration on the first night in EMG levels. METHODS: Ten asymptomatic healthy volunteers (mean age, 26.8 ± 3.78) were recorded for six sequential nights in their home environment using EMG D/A system. The device yields a nightly EMG level above threshold score on a 0-4 level. Because the data are categorical and nonparametric, the data of the ten subjects across six nights were submitted to a Friedman repeated measures ANOVA. The significant level was set as alpha equal to 0.05. RESULTS: The median and mode values of the subjects were tabulated and analyzed and we did not find a significant difference in EMG D/A level across the six nights (p = 0.287, Kendall's coefficient of concordance = 0.124, Friedman two-way repeated measures ANOVA). The data did show clear and substantial night-to-night variability. CONCLUSION: Substantial night-to-night variability in masseter EMG activity levels was clearly observed in our subjects. There was no evidence of a suppressed or elevated first-night effect-like variability on masseter muscle EMG level seen in these subjects using a small portable self-contained EMG detector/analyzer. These data suggest that recordings should be at least 5-6-nights duration to establish a reasonable measure of an individual's average nightly masseter EMG level.


Influence of resin coating materials on Porphyromonas gingivalis attachment.

Resin coating materials have been used for composite resin or provisional restoration in order to prevent plaque accumulation on their surfaces. However, it is not clear whether the coating materials influence attachment of periodontal bacteria. Therefore, we investigated the effect of resin coating materials on the attachment of Porphyromonas gingivalis (Pg). The polymerized auto cure resin plates were coated with two resin coating materials. To estimate the Pg attachment, each plate was immersed in brain heart infusion medium containing Pg. The quantity of bacteria attached on each plate was evaluated by crystal violet quantification. Morphological change of Pg was recorded using scanning electron microscopy. Both coating groups presented significantly lower Pg attachment compared to the control. The Pg shapes on the plates with resin coating materials were similar to the non-treated control plates. The resin coating materials clearly prevent Pg attachment on the polymerized auto cure resin plate.


Response shift in oral health-related quality of life measurement in patients with partial edentulism.

The purposes of this study were to determine whether a response shift was observable after partial denture treatment and to identify the predictors that influenced the response shift magnitude and direction. A total of 173 consecutive patients with no more than eight missing teeth who received implant-supported, fixed or removable partial dentures at Okayama University Dental Hospital were asked to complete a full-version Oral Health-Related Quality of Life (OHRQoL) questionnaire before (pre-test) and after treatment (post-test). Additionally, a short form (then-test) consisting of seven questions selected from the full version had its reliability verified and was utilised to retrospectively assess the pre-treatment OHRQoL status. The difference between the summary scores of the then-test and the pre-test determined the response shift magnitude and direction. The then-test mean score (22·9 ± 6·6) was significantly lower (worse OHRQoL) than that of the pre-test (26·4 ± 5·2). The response shift effect size was of moderate magnitude and negative direction (d = -0·78). A multiple regression analysis showed that age (younger patients) (P < 0·01), number of replaced teeth (fewer) (P < 0·01) and pre-test scores (lower) (P < 0·01) were the significant predictors for response shift. In conclusion, a response shift phenomenon with negative and moderate effect size was observed after partial denture treatment. The significant predictor variables were young age, fewer numbers of replaced teeth and lower pre-test scores.


Intradermal injection of Botulinum toxin type A alleviates infraorbital nerve constriction-induced thermal hyperalgesia in an operant assay.

Recent studies have shown that infraorbital nerve constriction (IoNC)-induced mechanical allodynia has been attenuated by administration of highly purified 150-kDa Botulinum neurotoxin type A (BoNT/A). Here, we extend these studies to determine whether BoNT/A could attenuate IoNC-induced symptoms of thermal hyperalgesia. Instead of testing head withdrawal thresholds, a thermal operant assay was used to evaluate cortical processing of sensory input following IoNC. In this assay, a fasted rat's desire to obtain a food reward (sweetened condensed milk) is coupled to its ability to tolerate facial contact with a warm (45 °C) thermode. Bilateral IoNC decreased the ratio of thermode contact duration/event, which is an indicative of thermal hyperalgesia. BoNT/A injection intradermally in the area of infraorbital nerve (IoN) innervation 7 days after IoNC resulted in decreased number of facial contacts and increased the ratio of contact duration/event (measured at 14 days after IoNC). The BoNT/A (2-200 pg) effects were dose dependent and statistically significant at 100 and 200 pg (P < 0·05). Complete reversal of thermal hyperalgesia symptoms was obtained with a 200-pg dose, without affecting sham rat behaviour. Off-site (neck) injection of BoNT/A did not relieve thermal hyperalgesia, while co-injection of BoNT/A with a neutralising antibody in the area of IoN innervation prevented relief of thermal hyperalgesia. Neither IoNC nor BoNT/A injection affected operant assay parameters with a 24 °C thermode, indicating selectivity of thermal hyperalgesia measurements. These results strongly suggest that intradermal injection of BoNT/A in the area of IoN innervation alleviates IoNC-induced thermal hyperalgesia in an operant assay.


施設に入所している要介護高齢者の問題点を抽出するテュートリアル演習の試み

施設に入所している要介護高齢者の問題点を抽出するテュートリアル演習の試み


Guidelines and recommendations for assessment of somatosensory function in oro-facial pain conditions--a taskforce report.

The goals of an international taskforce on somatosensory testing established by the Special Interest Group of Oro-facial Pain (SIG-OFP) under the International Association for the Study of Pain (IASP) were to (i) review the literature concerning assessment of somatosensory function in the oro-facial region in terms of techniques and test performance, (ii) provide guidelines for comprehensive and screening examination procedures, and (iii) give recommendations for future development of somatosensory testing specifically in the oro-facial region. Numerous qualitative and quantitative psychophysical techniques have been proposed and used in the description of oro-facial somatosensory function. The selection of technique includes time considerations because the most reliable and accurate methods require multiple repetitions of stimuli. Multiple-stimulus modalities (mechanical, thermal, electrical, chemical) have been applied to study oro-facial somatosensory function. A battery of different test stimuli is needed to obtain comprehensive information about the functional integrity of the various types of afferent nerve fibres. Based on the available literature, the German Neuropathic Pain Network test battery appears suitable for the study of somatosensory function within the oro-facial area as it is based on a wide variety of both qualitative and quantitative assessments of all cutaneous somatosensory modalities. Furthermore, these protocols have been thoroughly described and tested on multiple sites including the facial skin and intra-oral mucosa. Standardisation of both comprehensive and screening examination techniques is likely to improve the diagnostic accuracy and facilitate the understanding of neural mechanisms and somatosensory changes in different oro-facial pain conditions and may help to guide management.


非歯原性歯痛のガイドライン

非歯原性歯痛のガイドライン