label: url

en: Analysis of the sublingual artery using contrast-enhanced computed tomography

en: This in vivo study aimed to clarify the position of the sublingual artery (SLA) relative to the mandibular bone and to infer the potential risk for injury during dental implant surgery. Contrast-enhanced computed tomography images of the mouth of 50 edentulous patients (100 sides) treated at Tokushima University Hospital were reviewed. Curved planar reconstructed images perpendicular to the alveolar ridge were processed and classified into molar, premolar, canine, and incisor regions. The SLA and its branches were identified, and the distance from the mandible to the SLA was measured. The SLA was located close to the mandible (<2 mm) in the molar, premolar, canine, and incisor segments in 12.0% (95% confidence interval 5.6%-18.4%), 20.6% (12.6%-28.7%), 30.5% (21.3%-39.8%), and 41.8% (28.8%-54.9%) cases, respectively. The SLA was located within ±3 mm craniocaudally to the upper wall of the mandibular canal in the molar and premolar regions in 50% of cases and within ±5 mm craniocaudally to the mylohyoid ridge in the canine and incisor regions in the other cases, with no sex or age-related differences. The vertical distance from the alveolar ridge to the SLA was influenced by sex and age owing to alveolar resorption, indicating that the alveolar ridge is not a reliable reference for predicting SLA position. As the risk of SLA injury always exist during dental implant placement and there is no way to confirm the SLA pathways in a patient, clinicians must avoid injuring the sublingual soft tissue.

en: Clinical Implant Dentistry and Related Research


en: Reconstruction of rabbit mandibular bone defects using carbonate apatite honeycomb blocks with an interconnected porous structure.

en: Carbonate apatite (COAp) granules are useful as a bone substitute because they can be remodeled to new natural bone in a manner that conforms to the bone remodeling process. However, reconstructing large bone defects using COAp granules is difficult because of their granular shape. Therefore, we fabricated COAp honeycomb blocks (HCBs) with continuous unidirectional pores. We aimed to elucidate the tissue response and availability of COAp HCBs in the reconstruction of rabbit mandibular bone defects after marginal mandibulectomy. The percentages of the remaining COAp area and calcified bone area (newly formed bone) were estimated from the histological images. COAp area was 49.1 ± 4.9%, 30.3 ± 3.5%, and 25.5 ± 8.8%, whereas newly formed bone area was 3.0 ± 0.6%, 24.3 ± 3.3%, and 34.7 ± 4.8% at 4, 8, and 12 weeks, respectively, after implantation. Thus, COAp HCBs were gradually resorbed and replaced by new bone. The newly formed bone penetrated most of the pores in the COAp HCBs at 12 weeks after implantation. By contrast, the granulation tissue scarcely invaded the COAp HCBs. Some osteoclasts invaded the wall of COAp HCBs, making resorption pits. Furthermore, many osteoblasts were found on the newly formed bone, indicating ongoing bone remodeling. Blood vessels were also formed inside most of the pores in the COAp HCBs. These findings suggest that COAp HCBs have good osteoconductivity and can be used for the reconstruction of large mandibular bone defects. The COAp HCB were gradually resorbed and replaced by newly formed bone.

en: Journal of Materials Science. Materials in Medicine


en: A Case of Ameloblastoma Removed Using a Three-dimensional Transparent Plastic Jaw Model Which Can Visualize Internal Jawbone Structures

en: Journal of Oral Health and Biosciences

ja: Journal of Oral Health and Biosciences


en: ピロカルピン塩酸塩を用いた口腔リンス法の有用性と安全性の検討

ja: ピロカルピン塩酸塩を用いた口腔リンス法の有用性と安全性の検討

en: Oral Care

ja: 日本口腔ケア学会雑誌


en: Soluble Factor from Oral Cancer Cell Lines Inhibits Interferon-γ Production by OK-432 via CD40/CD40Ligand Pathway

en: Cancers

ja: Cancers


en: Evaluation of anatomical references for locating the course of the posterior superior alveolar artery for dental implant surgery

en: This retrospective cohort study aimed to identify the best anatomical reference for predicting the posterior superior alveolar artery (PSAA) location. Computed tomographic images of 90 maxillary sinuses were evaluated. We studied five references, including the alveolar crest, maxillary sinus floor, zygomatoalveolar crest, hard palate and soft palate, and measured the distances between them and the PSAA. Variations in the distance were evaluated by the standard deviation and coefficient of variation (CV). The zygomatoalveolar crest was an unstable reference, owing to its high standard deviation and CV. The smallest CV was for the distance between the alveolar crest and PSAA, although the distance was smaller in edentulous jaws than dentulous jaws. The distance between the sinus floor and PSAA was larger in male and edentulous patients. The PSAA was detected in 40.0%, 44.4%, 54.4% and 56.7% of the sinus walls at the first and second premolar and the first and second molar positions, respectively. At these tooth positions, the respective heights above the hard palate were 11.2 ± 4.9, 8.2 ± 4.9, 6.2 ± 2.8 and 8.1 ± 2.9 mm. The hard palate was the most stable reference for predicting the location of the PSAA, irrespective of sex, age and dentition.

en: International Journal of Oral and Maxillofacial Surgery


en: A clinical study on malignant lymphomas arising in the oral region

ja: 口腔領域に発症した悪性リンパ腫の臨床的検討

en: We examined the clinical characteristics of 18 cases of malignant lymphomas arising in the oral region which were diagnosed at our department during the 11 years from 2008 to 2018. The patients consisted of 10 males and 8 females whose mean age was 70.2 years. The primary site was the upper gingiva in 10 cases (55.6%), and the initial symptoms were tumor mass and swelling in 15 cases (83.3%). Only 7 cases (38.9%) were clinically diagnosed as malignant lymphoma at first visit, but the other 11 cases were difficult to diagnose correctly. The various clinical symptoms such as mass formation and ulcer made differential diagnosis difficult, and a definitive diagnosis could not be obtained by only a single biopsy. Therefore, we examined whether blood test results might be used as an indicator of the diagnosis or not. Our results showed that LDH in 8 of 17 cases (47.1%) and sIL-2R in 11 of 16 cases (68.8%) were high values. Furthermore, we examined whether lymphocyte-monocyte ratio (LMR) helped the diagnosis or not. Thirteen of 17 cases (76.5%) showed a low value of LMR. There was a significant difference in LMR compared to non-malignant lymphoma patients. LMR in the blood tests was also considered to be a useful marker for the diagnosis.

ja: 2008年から2018年までの11年間に当科で口腔領域に発症した悪性リンパ腫の18例について臨床的特徴を調べた．患者は，平均年齢が70.2歳の男性10例，女性8例であった．原発部位の10例(55.6%)は上顎歯肉で，初期症状は15例(83.3%)で腫瘤と腫脹であった．7例(38.9%)が初診時に臨床的に悪性リンパ腫と診断されたが，その他の11例は正しく診断することが困難であった．腫瘤形成や潰瘍のような様々な臨床症状が診断を困難にしており，1回の生検では確定診断が得られなかった．そこで，血液検査値が診断の指標であるかどうかを検討した．われわれの結果は，17例中8例のLDH(47.1%)と16例中11例のsIL-2R(68.8%)が高い値を示していた．さらに，われわれはリンパ球/単球数比(LMR)が診断に役立つかどうかを調べた．LMRの値は，17例中13例(76.5%)が有意に低く，非ML患者と比較しても有意差を認めた．以上のことより，LMRの血液検査も診断の補助的なマーカーであると考えられた．

en: Journal of Japan Society for Oral Tumors

ja: 日本口腔腫瘍学会誌


en: Histological comparison of three apatitic bone substitutes with different carbonate contents in alveolar bone defects in a beagle mandible with simultaneous implant installation.

en: Since bone apatite is a carbonate apatite containing carbonate in an apatitic structure, carbonate content may be one of the factors governing the osteoconductivity of apatitic bone substitutes. The aim of this study was to evaluate the effects of carbonate content on the osteoconductivity of apatitic bone substitutes using three commercially available bone substitutes for the reconstruction of alveolar bone defects of a beagle mandible with simultaneous dental implant installation. NEOBONE, Bio-Oss, and Cytrans that contain 0.1, 5.5, and 12.0 mass% of carbonate, respectively, were used in this study. The amount of newly formed bone in the upper portion of the alveolar bone defect of the beagle's mandible was 0.7, 6.6, and 39.4% at 4 weeks after surgery and 4.7, 39.5, and 75.2% at 12 weeks after surgery for NEOBONE, Bio-Oss, and Cytrans, respectively. The results indicate that bone-to-implant contact ratio was the largest for Cytrans. Additionally, the continuity of the alveolar ridge was restored in the case of Cytrans, whereas the continuity of the alveolar ridge was not sufficient when using NEOBONE and Bio-Oss. Both Cytrans and Bio-Oss that have a relatively larger carbonate content in their apatitic structure was resorbed with time. We concluded that carbonate content is one of important factors governing the osteoconductivity of apatitic bone substitutes.

en: Journal of Biomedical Materials Research. Part B, Applied Biomaterials


en: A case of microcystic adnexal carcinoma arising in the upper gingiva

en: Microcystic adnexal carcinoma (MAC) is a rare malignant tumor of skin appendages. MAC grows slowly, but is locally aggressive. The metastatic potential is low, but the recurrence rates are very high owing to insufficient dissection. The most common location of MAC is the skin of the midface of middle-aged adults. There has been no report about MAC arising in the gingiva. We report here an extremely rare case of MAC of the upper gingiva in a 53-year-old woman. She presented to our hospital with a 6-year history of a gradually increasing gingival mass. Intraoral examination revealed a smooth, poorly circumscribed mass with white granules resembling Fordyce spots on her upper gingiva. There was no bone destruction or regional lymph node swelling. The histopathological diagnosis was a tumor of skin appendages. Tumor resection was performed. Postoperative pathological examination revealed that the tumor differentiated into hair follicles and the sweat-gland-like structures and deeply infiltrated into muscle, perineural spaces, and bone. Since the surgical margins were positive, additional resection was performed after preoperative mapping biopsy. Finally, the tumor was completely excised. No tumor recurrence or metastasis have been observed over 1 year.

en: Japanese Journal of Oral & Maxillofacial Surgery

ja: 日本口腔外科学会雑誌


en: Fabrication of porous carbonate apatite granules using microfiber and its histological evaluations in rabbit calvarial bone defects

en: Carbonate apatite (CO Ap) granules are known to show good osteoconductivity and replaced to new bone. On the other hand, it is well known that a porous structure allows bone tissue to penetrate its pores, and the optimal pore size for bone ingrowth is dependent on the composition and structure of the scaffold material. Therefore, the aim of this study was to fabricate various porous CO Ap granules through a two-step dissolution-precipitation reaction using CaSO as a precursor and 30-, 50-, 120-, and 205-μm diameter microfibers as porogen and to find the optimal pore size of CO Ap. Porous CO Ap granules were successfully fabricated with pore size 8.2-18.7% smaller than the size of the original fiber porogen. Two weeks after the reconstruction of rabbit calvarial bone defects using porous CO Ap granules, the largest amount of mature bone was seen to be formed inside the pores of CO Ap (120) [porous CO Ap granules made using 120-μm microfiber] followed by CO Ap (50) and CO Ap (30). At 4 and 8 weeks, no statistically significant difference was observed based on the pore size, even though largest amount of mature bone was formed in case of CO Ap (120). It is concluded, therefore, that the optimal pore size of the CO Ap is that of CO Ap (120), which is 85 μm.

en: Journal of Biomedical Materials Research. Part A


en: Effects of acidic calcium phosphate concentration on setting reaction and tissue response to β-tricalcium phosphate granular cement.

en: Beta-tricalcium phosphate granular cement (β-TCP GC), consisting of β-TCP granules and an acidic calcium phosphate (Ca-P) solution, shows promise in the reconstruction of bone defects as it sets to form interconnected porous structures, that is, β-TCP granules are bridged with dicalcium phosphate dihydrate (DCPD) crystals. In this study, the effects of acidic Ca-P solution concentration (0-600 mmol/L) on the setting reaction and tissue response to β-TCP GC were investigated. The β-TCP GC set upon mixing with its liquid phase, based on the formation of DCPD crystals, which bridged β-TCP granules to one another. Diametral tensile strength of the set β-TCP GC was relatively the same, at ∼0.6 MPa, when the Ca-P concentration was 20-600 mmol/L. Due to the setting ability, reconstruction of the rat's calvarial bone defect using β-TCP GC with 20, 200, and 600 mmol/L Ca-P solution was much easier compared to that with β-TCP granules without setting ability. Four weeks after the reconstruction, the amount of new bone was the same, ∼17% in both β-TCP GC and β-TCP granules groups. Cellular response to β-TCP granules and β-TCP GC using the 20 mmol/L acidic Ca-P solution was almost the same. However, β-TCP GC using the 200 and 600 mmol/L acidic Ca-P solution showed a more severe inflammatory reaction. It is concluded, therefore, that β-TCP GC, using the 20 mmol/L acidic Ca-P solution, is recommended as this concentration allows surgical techniques to be performed easily and provides good mechanical strength, and the similar cellular response to β-TCP granules. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B, 2019.

ja: Journal of Biomedical Materials Research. Part B, Applied Biomaterials


en: 新規骨補填材としての炭酸アパタイトの開発と骨再生医療に向けて

ja: 新規骨補填材としての炭酸アパタイトの開発と骨再生医療に向けて

en: Journal of the Japanese Academy of Maxillofacial Prosthetics

ja: 顎顔面補綴