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Schwannomas are benign tumours that originate from the Schwann cells of the nerve. Despite the frequency of their occurrence in the head and neck, data relating to their clinicopathological features in the region are limited. This study reviews the clinicopathological characteristics and specific pathology of ancient (degenerative) change in 40 cases in the oral and maxillofacial region. Medical records were reviewed of the 40 cases treated at Tokyo Medical and Dental University Hospital Faculty of Dentistry between 2000 and 2020. The most frequently involved site was the tongue, and the average tumour size was 13.2 mm. Degenerative changes were observed in eight cases. All tumours were completely excised through biopsy or local excision, and no recurrence was observed on clinical follow up. Statistical analyses revealed significant associations (p 0.05) between ancient change and tumour size, and between ancient change and the apparent diffusion coefficient (ADC) value derived from diffusion-weighted magnetic resonance imaging (MRI). Analysis suggests that schwannoma progresses over a long period and subsequently undergoes secondary ancient changes. Pathological events such as cystic formation and haemorrhage that are associated with ancient changes, cause hypocellularity and lead to high ADC values. These values may indicate ancient change and should be considered when distinguishing schwannoma from other lesions.

Objectives Cysts of the mandible are common and are often found clinically in oral surgery. Marsupialization for relatively large cystic lesions may be performed to reduce the size of the lesion and to obtain a histopathological diagnosis. For cystic lesions of the mandible, the effect of marsupialization has many advantages, such as a reduction in lesion size, the avoidance of mental nerve palsy, and preservation of the teeth. It is still unclear whether there is a difference in the reduction rate based on patient age and pathology (dentigerous cyst, odontogenic keratocyst, radicular cyst, ameloblastoma (unicystic type)) and initial size of the lesion. Methods The subjects included 55 patients with cystic lesions with a major axis of 3 cm or greater (16 dentigerous cysts, 20 odontogenic keratocysts, 7 radicular cysts, and 12 ameloblastoma) who underwent treatment at our department. Using simulation software (ProPlanCMF®), the volume of the lesion was extracted from the CT data before and after the marsupialization, and the three-dimensional reduction rate before and after marsupialization was calculated. Results No significant difference was observed between the subgroups in terms of histopathological diagnosis, patient age or size of lesion. Although the effect of marsupialization on cystic lesions with a major axis of 3 cm or more showed a significant difference between 3.0 months and 4.5 months, the difference was not significant between 4.5 months and 6.0 months. Conclusions An indication for the enucleation timing after marsupialization is 4.5 months when the rate of decrease after fenestration slows down.

Owing to a high recurrence rate, radical jaw resection is regarded as the first choice of treatment for odontogenic myxoma. However, there have been several reports on the effectiveness of conservative surgical treatment preserving inferior alveolar nerve for odontogenic myxoma of the mandible. A 37-year-old woman presented with a complaint of pain around her mandibular left third molar. Odontogenic myxoma was diagnosed by using biopsy. The tumor occupied a part of the cortical bone and contained the inferior alveolar nerve. We performed enucleation and curettage, which preserved the inferior alveolar nerve. Ten years after the treatment, there were no symptoms of recurrence or nerve paralysis. Here, we discuss the conservative treatment of odontogenic myxoma, focusing on inferior alveolar nerve preservation.

A dermoid cyst is lined by an epidermis-like epithelium with dermal adnexal structures contained within the cyst wall. The “sac of marbles” sign is a characteristic image finding of a dermoid cyst but its pathogenesis is unknown. In this report, we aim to elucidate the cause of the sac of marbles using immunohistological studies. We report the case of a 39-year-old man with a dermoid cyst in the floor of the mouth with a “sac of marbles” sign that was revealed by magnetic resonance imaging. We analyzed the histology of the sac of marbles in dermoid cysts and performed an immunohistological analysis of keratin subtypes. Histopathologically, the sac of marbles contained a spherical accumulation of anucleated epithelial cells; immunohistochemistry revealed that it was positive for keratin1 and keratin 10 and was negative for keratin 15 and keratin 17, demonstrating the same direction of differentiation as the cyst-lining epithelium. The results of this study show that the sac of marbles originates from denatured keratin derived from the lining epithelium.

Purpose To retrospectively evaluate skeletal stability after Le Fort I maxillary impaction surgery and mandibular autorotation without bilateral sagittal split osteotomy (BSSO) in high-angle class II patients. Materials and methods Seven female high-angle class II patients who underwent maxillary impaction surgery and mandibular autorotation without bilateral sagittal split osteotomy were included in this study. Surgical changes and relapse were measured on lateral cephalograms taken preoperatively and at 1 month, 6 months and 1 year postoperatively. Results The horizontal movement of the maxilla at point A was 5.8 ± 3.3 mm backward, and the upward movement at the posterior nasal spine was 3.3 ± 1.4 mm. The mean horizontal change at point A during the 1-year follow-up period was 0.1 ± 0.2 mm, and the vertical change at posterior nasal spine was 0.2 ± 1.3 mm, which were not statistically significant. The horizontal surgical change at point B was 4.0 ± 1.8 mm forward and the vertical surgical change at point B was 4.7 ± 1.8 mm upward. Postoperative relapse was 10.9% and 13.7% in the horizontal and vertical directions, respectively. Conclusions Le Fort I maxillary impaction surgery with mandibular autorotation may be 1 of the suitable procedures for high-angle class II patients.

BackgroundMaxillary gingival squamous cell carcinoma (MGSCC) occurs rather infrequently, compared to tongue and mandibular gingival carcinomas, among the cancers of the oral cavity. Therefore, significant numbers of MGSCC cases have not been statistically analysed. The aim of this study is to clarify the prognostic factors for MGSCC. MethodsWe performed the statistical analysis of 90 MGSCC cases primarily treated in our department from 1999 to 2014. ConclusionsThe patients (male: 36, female: 54) were aged between 38 and 93 years, and the mean age was 68.7 years. The number of patients in each tumour stage according to the TNM classification was as follows: T1: 15 cases, T2: 32 cases, T3: 13 cases, and T4: 30 cases. Forty-two patients were treated only by surgery, 5 only by radiotherapy, 3 by preoperative radiotherapy and surgery, and 40 patients were treated by combination therapy with preoperative chemoradiotherapy and surgery. Neck dissections were performed in 40 cases including 29 cases (11 primary and 18 secondary cases) of histopathologically diagnosed lymph node metastases. Extranodal extension was found in 74.3% cases with metastatic lymph nodes. The 5-year overall survival rate was 81.9%. In univariate analysis, the site of occurrence, stage of tumour, lymph node metastasis, and treatment contributed to the 5-year survival rate. Multivariate analysis demonstrated that the site of occurrence (posterior region) was an independent prognostic factor. Seventeen deaths occurred due to the primary disease, while three deaths were caused by other diseases. ConclusionThe posterior region cancers, according to the classification based on site of occurrence, were independent predictors of poor 5-year overall survival rate.

Objective The objective of this study was to investigate the prognostic effects of clinical and histologic findings in patients with mucoepidermoid carcinoma (MEC) of minor salivary glands. Study Design This retrospective clinical review included 63 patients (30 males, mean age 52.8 years) with minor salivary gland MEC treated at our hospital from 1994 to 2019. Overall survival (OS) or disease-free survival was determined using the Kaplan-Meier limit method. Correlations between different factors and survival rates were assessed using chi-square tests. Results The 10-year OS rate was 91.2%. Low- or intermediate-grade MEC had a good prognosis regardless of the surgical margin, whereas high-grade MEC had a poor 10-year OS rate (64.2%). Ten patients developed recurrence or metastasis after primary surgical resection, of whom 6 were diagnosed with a high-grade tumor. The most frequently affected site was the palate, whereas the mandibular gingiva was the most commonly affected site during recurrence. Of 4 patients who received chemotherapy and/or radiotherapy postsurgery, 2 had local recurrence and/or neck lymph node metastasis and 1 died from MEC. Conclusion Patients with low- or intermediate-grade MEC exhibited satisfactory survival after surgery. In patients with high-grade tumors, it has been suggested that survival rates are poor and do not improve following adjuvant therapy.

Summary: Total joint replacement (TJR) of the temporomandibular joint (TMJ) is a promising surgical procedure and device for treating end-stage diseases of the TMJ. For the functional and aesthetic reconstruction of the oral and maxillofacial head and neck region, TMJ TJR significantly helps maintain the patient’s quality of life in terms of a better diet, mastication, speech and social interaction. TMJ TJR was approved by regulatory authorities in 2019 in Japan, thus enabling the clinical application of the TJR system. However, the surgery demands particularly difficult and high-risk procedures, necessitating the prudent selection of indicated patients. The joint committee of the Japanese Society of Oral and Maxillofacial Surgeons and Japanese Society for Temporomandibular Joint is working together to develop an appropriate clinical guideline for TMJ TJR.

Objective Regenerating loss of bone and nerve tissue is a serious concern among oral and maxillofacial surgeons, yet there is little information regarding the connection between bone metabolism and the nervous system. This study aimed to obtain evidence of this connection. Methods Osteocyte and Schwann cell lines were maintained in a non-contact co-culture system. Quantitative reverse-transcription polymerase chain reactions, immunoblot analyses, and cell proliferation assays were performed. The dendrite length of osteocytes was analyzed quantitatively. Results The dendrite length of osteocytes co-cultured with Schwann cells was significantly increased and associated with E11 protein expression. Schwann cell culture supernatant inhibited osteocyte proliferation and promoted dendrite elongation. However, myelin basic protein in Schwann cells was upregulated in the presence of osteocyte culture supernatant without changes in proliferation and dendrite extension. Schwann cells express the Sema3A gene and co-culture with osteocytes enhanced Sema3A mRNA expression. Conclusions Our data suggest that Schwann cells promote osteocyte maturation via humoral factors including Sema3A and osteocytes regulate myelination of Schwann cells.

Objective: Bone and nerve reconstruction is crucial for treating various diseases of the oral and maxillofacial region. However, the relationship between the bone and the nervous systems is not fully elucidated. Methods: Osteoblastic and sympathetic neuronal cell lines were maintained in contact co-culture. Quantitative reverse-transcription polymerase chain reaction (RT-qPCR), immunoblot analysis, RNA interference, alkaline phosphatase (ALP) activity, and mineralization assays were performed. Results: Contact co-culture enhanced osteoblast calcification, promoted ALP activity, and increased the expression of Bglap and Runx2. Knockdown of Sema3A by RNA interference did not completely inhibit RUNX2 expression in contact co-culture. Sympathetic neuronal cells produce BMP-2; Bmp2 expression was upregulated in contact co-culture. Conclusions: We showed that sympathetic neuronal cells promote osteoblast differentiation by contact co-culture with osteoblasts, partly via SEMA3A. BMP-2 from sympathetic neuronal cells may promote osteoblast differentiation in a contact co-culture system.

Objective The aim of this study was to investigate postoperative horizontal relapse of the mandible in terms of the effects of the magnitude of mandibular setback movement and ramus inclination after LeFort I osteotomy and sagittal split ramus osteotomy. Study Design A retrospective study of patients who underwent orthognathic surgery for mandibular prognathism was performed. Postoperative relapse at point B was analyzed with regard to the magnitude of mandibular setback and the ramus inclination. Serial cephalograms were used to measure surgical changes and evaluate postoperative relapse. Results Nineteen men and 31 women (mean age 23.1 years) were retrospectively enrolled. Mean surgical backward movement of the mandible at point B was 8.2 mm, mean ramus inclination was 3.56 degrees, and mean relapse 1 year postoperatively was 0.95 mm (11.6%). Horizontal relapse of the mandible was significantly correlated with the magnitude of mandibular setback (r = –0.52; P = .007) and ramus inclination (r = 0.48; P = .014). Conclusions Increased horizontal mandibular relapse after bimaxillary surgery was associated with greater mandibular setback movement and increased proximal segment clockwise rotation. Mandibular relapse after bimaxillary surgery may be minimized via adequate control of intraoperative clockwise rotation of the proximal segment.

Giant cell arteritis (GCA) is a granulomatosis accompanied by angiitis that affects medium- and large-sized arteries. We present a case of GCA in a patient who presented with jaw claudication and occlusal pain. A 78-year-old man visited our department with left-sided facial pain associated with mastication. He also reported spontaneous left-sided facial pain and diminished vision. Based on his age, his new-onset left-sided headache, and a high erythrocyte sedimentation rate, he was diagnosed with GCA with immediate initiation of prednisolone (PSL) therapy. His fever subsided the following day. A temporal artery biopsy (TAB) was performed 7 days after hospitalization and showed a false-negative result. His left-sided facial pain and headache subsided 29 days after therapy initiation. He was diagnosed with bladder cancer 3 months later, and we considered a probable association between his left-sided facial pain and paraneoplastic syndrome. GCA was diagnosed clinically based on the American College of Rheumatology criteria. Prompt PSL treatment is warranted without waiting for TAB results to avoid visual loss or other complications in this patient population.

Maxillary non-union is a rare complication that occurs after an orthognathic surgery such as Le Fort I osteotomy. Here, we report a case of refractory non-union after maxillary osteotomy, which required a second surgery with bone graft. A 33-year-old man who had undergone bimaxillary osteotomy complained of an abnormal sensation in the right alar part about 1 year after the surgery. The patient was diagnosed as having maxillary non-union. Although surgical stabilization was performed using titanium plates, the non-union remained. The re-fusion surgery was performed about 3 years after the bimaxillary osteotomy with autologous bone graft using a biodegradable fixation system. At the 1-year follow up, the maxillary non-union was healed both clinically and radiographically. Re-fusion surgery using bone graft with biodegradable fixation might be an effective treatment option in cases of prolonged non-union that becomes evident after a long period following the initial maxillary osteotomy.

The aim of this study is to report the differences in clinicopathological features of oral tongue squamous cell carcinoma (OTSCC) and survival between adolescent and young adult (AYA) patients and elderly patients and to find the prognosticators. The medical records of 101 AYA patients and 175 control patients with OTSCC who underwent surgery were reviewed. Variables related to prognosis and their clinicopathological associations were analyzed. The 5-year overall survival (5y-OS) rates of AYA and control patients with stage I and II OTSCC were 94.4% and 89.6% (P = .353), respectively, and their 5-year disease-free survival (5y-DFS) rates were 82.0% and 76.6%, respectively (P = .476). The 5y-OS rates of patients with stages III and IV OTSCC were 83.3% and 66.7% (P = .333), respectively, and their 5y-DFS rates were 75.0% and 57.1% (P = .335), respectively. Logistic regression analysis revealed that there was no significant clinicopathological difference in AYA and control group. Furthermore, there was no significant difference in 5y-OS rates between patients who underwent elective neck dissection (END) and those who underwent therapeutic neck dissection (TND) in both group (P = 0.717 and 0.688). Overall, the present study revealed the clinicopathological features and prognosis of OTSCC were similar in AYA patients and elderly patients. Moreover, as there was no significant difference in OS between patients who underwent END and those who underwent TND in AYA and control groups, our results suggest that the indication for END in AYA patients with clinical N0 OTSCC is similar to that for elderly patients.

Introduction and importance Pediatric temporomandibular joint (TMJ) ankylosis can lead to significant difficulties in opening the mouth, as well as stunted mandibular growth resulting in a small mandible and facial asymmetry. For pediatric TMJ ankylosis, the ideal time to perform TMJ mobilization in order to achieve standard mandibular growth is unclear. Case presentation An 11-year-old boy with limited mouth opening was referred to our hospital. The patient had previously sustained a fracture of the left articular process of the mandible. Clinical examination revealed bony ankylosis of the left TMJ, and the condylar head was dislocated anteromedially. The bony ankylosis was removed at the age of 12 years. Mouth-opening exercises were started postoperatively. His mouth opening recovered without the development of severe facial asymmetry, and the dislocated condylar process served as a new joint and provided good jaw function until the most recent follow-up at the age of 21 years. Clinical discussion It is practical to perform surgical intervention after the child has achieved some growth and at a time when the surgery would not interfere with jaw development because the mouth opening can be improved by postoperative physical therapy. No interpositional implant was used because strict postoperative mouth opening exercises and the displaced condylar process, which was maintained to almost normal TMJ structure, were expected to preserve the gap between the ramus and the zygomatic arch. Conclusion Surgical intervention in the appropriate growth period is important to prevent the sequelae of mandibular growth suppression due to pediatric TMJ ankylosis., Highlights • We describe a case of pediatric temporomandibular joint ankylosis. • It can cause limited mouth opening, a small mandible, and facial asymmetry. • We observed good treatment outcomes and jaw function with a 9-year follow-up. • Mouth opening recovered without the development of severe facial asymmetry. • Arthroplasty in the appropriate growth period can prevent adverse effects.

Patients with masticatory muscle tendon-aponeurosis hyperplasia (MMTAH) experience limited mouth opening due to restricted muscle extension. Hyperplastic aponeurosis and tendons lead to the restriction of muscle extension. The criteria for the diagnosis of MMTAH are limited mouth opening that progresses very slowly from adolescence, intraoral palpation reveals a hard cord-like structure along the overhang of the anterior border of the masseter muscle on maximum mouth opening, and a square mandible. Conservative treatment, including pharmacotherapy, occlusal splint and physical therapy are ineffective. The standard therapy is surgical treatment, such as anterior partial aponeurectomy of the masseter muscle and coronoidectomy. The long-term results are very satisfying.

The purpose of the current study was to compare the 1-year stability of skeletal after original Le Fort I osteotomy and maxillary step osteotomy. Fifty-two patients with prognathism underwent sagittal split ramus osteotomy with either original Le Fort I osteotomy or maxillary step osteotomy (26 patients each). Twelve cephalometric parameters were measured to evaluate postsurgical stability (lesser change was considered as enhanced stability) at 1 month (T1), 6 months (T2), and 1 year (T3) postoperatively. Only 3 parameters—vertical and horizontal distance of menton and vertical distance of point B—showed minimal but significant differences between the two groups. Lesser degrees of changes were observed after maxillary step osteotomy than after original Le Fort I osteotomy, and the differences were significant during the period between T1 and T2, but not from T1 to T3. Differences between the two groups were less in asymmetry cases required correction of the occlusal plane. In conclusion, differences between original Le Fort I osteotomy and maxillary step osteotomy were observed at the frontal points of the mandible; however, they were not clinically significant. It may be suggested that there is no significant difference in skeletal stability at 1 year after the two procedures.

Objective Masticatory muscle tendon-aponeurosis hyperplasia (MMTAH) is a disease which exhibits limiting mouth opening caused by hyperplasia of the tendon and aponeurosis of bilateral masticatory muscles. Although it is unclear whether hyperplasticity of tendons in MMTAH is due to cyclic stretch, we hypothesize that cyclic stretch is the main cause of force on MMTAH. In this study, we examined decorin expression in the masticatory muscle tendon of MMTAH patients. We also examined decorin (Dcn) expression of tenocytes on which stretch forces are loaded to explore whether stretch forces affect yes-associated protein (YAP) signaling and whether Dcn expression is regulated by YAP. Methods Quantitative reverse-transcription polymerase chain reaction, immunoblot analysis and immunohistochemistry were performed in tendons of patients having MMTAH. Mechanical loading experiment for TT-D6 tendon fibroblastic cells using RNA interference technique was conducted. Results We found that Dcn expression is increased in tendons of MMTAH patients. We also showed that cyclic stretch force increases decorin expression in TT-D6 tendon fibroblastic cells and that Dcn expression is regulated via YAP in TT-D6 tendon fibroblastic cells acted upon by cyclic stretch. Conclusions Our results, for the first time, demonstrated that cyclic stretch induces decorin expression via YAP in tenocytes and Dcn is upregulated in tendons of MMTAH, suggesting that tendons of MMTAH were subjected to cyclic stretch conditions.

Pyogenic granuloma (PG) is a granulomatous elevated lesion that occurs on the skin and mucous membranes. We herein report two cases of intra-oral PG that developed during the administration of ramucirumab for gastric cancer. Case 1 involved a 55-year-old man with a 6-mm tumor on the right tongue, and case 2 involved a 67-year-old man with a 5-mm tumor on the upper lip. The imbalance in angiogenesis caused by ramucirumab and the deterioration in the local oral environment were suggested to have caused the PG. Medical and dental collaboration is essential during the administration of ramucirumab.

To evaluate the stiffness of tongue squamous cell carcinoma (TSCC) using ultrasound strain elastography, a relatively new sonographic imaging technique, and to identify the factors that affect this stiffness. We treated 62 patients diagnosed with muscle invasive TSCC, who were treated at the department of oral surgery of our institution. Each patient’s tumor stiffness was semi-quantified according to the ratio of cancer to tongue muscle strain measured using ultrasound strain elastography (the strain ratio). Histopathological diagnosis was made on the same section as the ultrasound strain elastography. We set the following histopathological parameters: cancer cell content in the tumor area (%CCC), collagen fiber content in the tumor area (%CFC), and tumor-infiltrating inflammatory cell content in the stromal compartment (%TIIC). Spearman's rank correlation (rs) was used to assess correlations, and P values

BackgroundDiffuse large B-cell lymphoma (DLBCL) is the most common type of lymphatic tumor; however, extranodal DLBCLs that exhibit initial symptoms in the maxilla and mandible are rare. Moreover, DLBCL is clinically classified as a moderate to highly malignant lymphatic tumor that can progress rapidly; therefore, early diagnosis is crucial. However, diagnosis is difficult because the disease causes a diverse range of clinical symptoms with no characteristic imaging findings. We conducted a clinical investigation to clarify the clinical characteristics of DLBCL exhibiting initial manifestation in the maxilla and mandible.MethodsOf the 2748 patients with malignant tumors of the oral and maxillofacial region examined during a period of 11 years between January 2006 and December 2016 at our hospital, 27 primary cases diagnosed with DLBCL based on the chief complaint of symptoms in the gingiva and bone of the maxilla and mandible were enrolled. We evaluate on sex, age, whether treatment was provided by a previous physician, symptoms, disease period until seeking treatment, clinical diagnosis, laboratory findings, and imaging results.ResultsThere were 15 cases with maxilla involvement and 12 with mandible involvement. The median disease period until seeking of treatment was 60 d (3–450 d). All cases exhibited a tumor or a mass, and hypoesthesia of the chin was confirmed in 8 cases with mandible involvement. The clinical stage was stage I in 8 cases, stage II in 10 cases, and stage IV in 9 cases. Serum lactate dehydrogenase (LDH) levels were elevated in 13 of 22 patients. The overall survival rate was 63%.ConclusionThe possibility of Malignant Lymphomas (MLs), such as DLBCL, must be considered while treating lesions of the oral and maxillofacial region.

Adenoid cystic carcinoma (AdCC) is a rare, indolent salivary gland tumor that is reported to be driven by fusion genes. However, MYB/MYBL1-NFIB fusions have been detected in60% of all AdCC cases and the oncogenic driver mutations in approximately 40% of AdCC remain unknown. Our aim was to identify novel gene fusions in AdCC.We investigated 20 AdCC cases using a targeted RNA sequencing panel to identify gene fusions and performed quantitative real-time reverse transcription polymerase chain reaction to assess MYB, MYBL1, and NFIB expression levels.A total of 36 fusion transcripts in 15 cases were detected and validated by Sanger sequencing. The MYB-NFIB and MYBL1-NFIB fusion genes were detected in 9 and 3 cases, respectively, in a mutually exclusive manner. Furthermore, novel gene fusions, namely, NFIB-EPB41L2, MAP7-NFIB, NFIB-MCMDC2, MYBL1-C8orf34, C8orf34-NFIB, and NFIB-CASC20, were identified. Among them, NFIB-EPB41L2 and NFIB-MCMDC2 are thought to activate MYB and MYBL1 expression, respectively, through the insertion of a genomic segment in proximity to MYB and MYBL1 genes, respectively.Six novel gene fusions other than MYB/MYBL1-NFIB were identified. The detection of novel fusion genes and investigation of the molecular mechanism will contribute to the development of novel molecular targeted therapies for this disease.

Summary Background Currently, sequential morphological changes of vascularized scapular bone for mandibular reconstruction have remained unreported. Methods We retrospectively analyzed 18 patients with defects on the lateral segment of the mandible who underwent postoperative computed tomography (CT) scanning at 1, 6, 12, and 24 months postoperatively. Using the cross-sectional coronal CT images during each assessment, we measured the height and thickness of the grafted scapular bone at points 10 and 30 mm away from the mesial segment and evaluated their differences over time. Then, the relationship between the morphological changes of the grafted scapular bone and the distance from the mesial bone segment, the number of occlusal supports on the contralateral side of the mandible, and the correlation of sex and age were evaluated. Results The height of the grafted scapular bone decreased by approximately 11% and its thickness increased by 14% within 24 months postoperatively. The bone thickness increase was greater at point 30 mm from the mesial bone segment. Patients with two occlusal contacts (premolar and molar) on the contralateral side had a significantly higher rate of bone thickness increase. Furthermore, the graft morphology was not associated with age or sex. Conclusion A vascularized scapular bone thickens over time, which depends on the distance from the mesial bone segment and the occlusal contact regions on the contralateral side of the mandible.

In the bilateral sagittal split osteotomy, a short lingual cut is made on the medial side of the ramus; however, in some cases, a true fracture occurs on the buccal side of the ramus. The purpose of this study was to evaluate the relationship between the splitting pattern of the mandible and the form of the mandible, the surgical technique used, and the postoperative occurrence of relapse after 'unfavorable' splits. The investigation examined 143 patients in whom a short lingual cut was attempted. The rate of unfavorable split was 14.7% (42/286). A strong correlation was observed between the reach of the lateral bone cut to the inferior border of the mandible and an unfavorable split. According to multivariate regression, the factors leading to an insufficient lateral bone cut were the degree of inward curvature of the ramus (P=0.001) and the position of the lateral bone cut (P=0.002). There was no significant difference in relapse between cases of unfavorable and normal splits. An unfavorable split does not affect the prognosis of the occlusion, but it is important to confirm the inward curvature of the ramus and set the position of the lateral bone cut adequately to avoid unfavorable splits.

Fifty-four patients diagnosed with paresthesia on one side of the lower lip or skin in the chin area, were examined by multiple sensory tests and assessed self-reported subjective symptoms and the psychological state through questionnaires. Additionally, they were followed over time. Each sensory test threshold was evaluated and classified according to the individual way of scoring system, and the average sensory score (ASS) was used to analyze the correlation between self-reported symptoms and psychological state. On the second visit, all sensory test results had improved. The ASS was positively correlated with the pain questionnaire on the first visit; however, it did not correlate with psychological state or personality. There was a positive correlation between neuroticism and anxiety scores. The index of change (IC) of the ASS over time did not correlate with the IC of patients' self-reported symptoms or mental state. The IC of ASS data improved in all patients, but self-reported subjective symptoms did not show signs of improvement in all patients. When patients were divided into two groups according to age or sex, older females showed significantly more improvement than younger males on the psychological test.

OBJECTIVE Masticatory muscle tendon-aponeurosis hyperplasia, which is associated with limited mouth opening, progresses very slowly from adolescence. The prevalence rates of this disease are higher among women than among men, suggesting oestrogen involvement. As parafunctional habits are frequently observed, mechanical stress is likely involved in the pathogenesis and advancement of this disease. To elucidate the pathological condition, we examined the effect of oestrogen on tenocyte function and the relationship between mechanical stress and crystallin beta A4 (Cryba4), using murine TT-D6 tenocytes. MATERIALS AND METHODS Cell proliferation assays, RT-PCR, real-time RT-PCR, Western blot analysis and mechanical loading experiments were performed. RESULTS The physiological dose of oestrogen increased the levels of scleraxis and tenomodulin in TT-D6 tenocytes. In contrast, forced expression of Cryba4 inhibited scleraxis expression in these cells. Surprisingly, oestrogen significantly promoted cell differentiation in the Cryba4-overexpressing TT-D6 tenocytes. Moreover, tensile force induced Cryba4 expression in these tendon cells. CONCLUSION Oestrogen and Cryba4 may be associated with the progression of masticatory muscle tendon-aponeurosis hyperplasia.

It is well known that osteonecrosis of the jaw is induced by the adverse effect of medication including bisphosphonates and anti-receptor activator of nuclear factor-kappa B ligand antibody. Recently, a few case reports showed that methotrexate is capable of inducing osteonecrosis of the jaw in the absence of antiresorptive or antiangiogenic agents. We herein introduce a case of osteonecrosis of the jaw with pancytopenia by low-dose methotrexate administration for rheumatoid arthritis. The patient of this case has been extracted teeth and subsequently suffered from the pain osteonecrosis of the jaw. Referring to our hospital, the patient was diagnosed as disseminated intravascular coagulation. Being received appropriate treatment, his condition was gradually recovered and he was discharged at thirty days after admission. We should bear this case in mind in examining patients being prescribed methotrexate.

Objectives In patients with advanced oral squamous cell carcinoma (OSCC), surgical treatment is often administered in combination with radiotherapy-based postoperative adjuvant therapy. The aim of the present study was to determine the most appropriate dose by comparing patient outcomes between doses of 50- and 66-Gy for postoperative cervical irradiation. Materials and methods This retrospective study included patients who underwent postoperative cervical irradiation following neck dissection for OSCC with lymph nodes metastases, and their primary lesions were controlled. They were divided into the 50- and 66-Gy irradiation groups and were examined for sex, age, primary lesion site, tumor/node/metastasis stage, initial treatment for primary cancer, neck dissection procedure, number of metastatic lymph nodes, presence or absence of extranodal extension (ENE), concomitant anticancer agents, and therapeutic outcomes. Results A total of 78 patients met the clinical criteria for study enrollment. The 50- and 66-Gy postoperative cervical irradiation groups included 40 and 38 patients, with neck dissection performed at 45 and 38 sites, respectively. Cervical control rate was 97.5% and 97.3% in the 50- and 66-Gy irradiation groups (p = 0.74). The cumulative disease-specific 5-year survival rate was 85.6% and 88.3%, respectively, with no significant difference (p = 0.64). Conclusion The findings of our study indicate that the irradiation dose of 50 Gy is appropriate for postoperative cervical irradiation in patients with OSCC.

This study re-examined the usefulness of surgery for the management of masticatory muscle tendon-aponeurosis hyperplasia (MMTAH) through a comparison of the outcomes between patients who underwent surgery and those who did not. The duration of follow-up was 2 years. Twenty-eight patients who attended the study hospital and were given a diagnosis of MMTAH were included. Nineteen patients underwent surgery (surgical group) and nine patients were instructed to open their mouths wide once a day and did not undergo surgery (non-surgical group). Maximum mouth opening, impairment of daily activities, satisfaction, and the status of mouth opening training were evaluated after surgery. The mean increase in mouth opening after 2 years was 20.2mm in the surgical group and 2.4mm in the non-surgical group. Adequate mouth opening training led to satisfactory results 2 years postoperative, and sustained mouth opening training for 6 months after surgery was a key factor for obtaining good outcomes. The general condition and personality of individual patients should be evaluated carefully before surgery to estimate whether or not they can endure the pain associated with postoperative mouth opening training. The results of this study suggest that the surgical procedure is useful for the management of MMTAH.

Objective Peripheral blood-derived inflammation-based scores, such as the neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), and the combination of platelet count and NLR, have recently been proposed as prognostic markers in solid tumors. The purpose of this study was to investigate the validity of inflammatory markers as predictive prognostic factors for locally advanced oral squamous cell carcinoma (OSCC). In addition, we evaluated the potential correlation between systemic inflammation and local expression of COX2. Study Design Retrospective chart review and histologic analysis. Setting Tertiary referral academic center. Subjects and Methods We conducted a retrospective analysis of 94 patients with advanced OSCC treated with surgery at our hospital between 2007 and 2015. The relationship among patient survival, systemic inflammatory markers, and local COX2 expression was evaluated. Local COX2 expression in surgical specimens was measured by immunohistochemistry. Results High NLR and high PLR were associated with significantly shorter overall survival and cancer-specific survival. Multivariate analysis revealed that cN stage, NLR, and postoperative radiation/chemoradiation were significantly associated with overall survival and cancer-specific survival. PLR and combination of platelet count and NLR were significantly correlated with tumor expression of COX2. Finally, patients with cN2 stage disease and high local COX2 expression had a significantly worse prognosis than other patient groups. Conclusion Pretreatment inflammatory markers are useful as prognostic factors in advanced OSCC. Our study suggests that local COX2 may be affected by systemic inflammation and that the prognostic impact of COX2 expression depends on host factors and tumor characteristics.

Purpose In 2013, we reported the results of a third-generation oral moisture-checking device in a multicentre clinical study involving patients with dry mouth and healthy volunteers. Subsequently, several improvements have been made to the third-generation device, and a fourth-generation device is now commercially available. This study aimed to confirm the usefulness of this improved fourth-generation device in the diagnosis of dry mouth and to assess the physiological wetness of lingual mucosa by using this device. Materials and Method This multicentre study comprised subjects with dry mouth (dry mouth group) and those without dry mouth (healthy group). Results In this study, the degree of moisture was considerably different between the two groups. Receiver operating characteristic analysis revealed an area under the curve value of 0.831. Sensitivity and specificity values were close to 80% in cases where the degree of moisture ≥29.6 was defined as normal, ≤27.9 was defined as dry mouth, and 28.0–29.5 was defined as borderline dry mouth. Conclusions These results suggest that the improved fourth-generation moisture-checking device can be used for the diagnosis of oral dryness.

Background: Synovial chondromatosis is usually detected at a late stage based on free bodies in joint space. The purpose of this study was to identify biomarkers for cell proliferation and chondrogenesis in the primary stage of synovial chondromatosis in the temporomandibular joint (TMJ).Clinical Presentation: A 67-year-old female was referred for right side TMJ pain. Magnetic resonance imaging (MRI) findings suggested an intra-joint space lesion, but no free bodies were observed intraoperatively. Pathological examination led to diagnosis of Milgram stage 1 synovial chondromatosis. Biomarkers related to mesenchymal stem cells (MSCs), cell proliferation, and chondrogenesis were observed in immunohistopathological examination of specimens.Clinical Relevance: The findings suggest that MSCs with chondrogenic potential and growth activity are present at the start of cartilage formation in the synovial membrane. These cells may be the origin of disease. Those findings improve understanding of the etiology and disease progression of synovial chondromatosis in the TMJ.

Objectives: To investigate the role of non-receptor tyrosine kinases (NRTKs) in inflammation-induced osteoclastogenesis.Methods: Microarray analyses of global mRNA expression during recepto...

This paper reports data on the bone, specifically the tibia and mandible, of nonobese diabetic mice with severe combined immunodeficiency disease (NOD–SCID mice) treated with zoledronic acid (ZA) and prednisolone (PSL). The data described here are related to the research article titled “Zoledronic acid basically increases circulating soluble RANKL level in mice, and in glucocorticoid-administrated mice, more increases lymphocytes derived sRANKL by bacterial endotoxic stimuli” [1]. The present data and the NOD–SCID mice experiments described contain insights into the role of bone-remodeling factors induced by ZA treatment. Keywords: Zoledronic acid, NOD–SCID mice, Medication-related osteonecrosis of the jaw

Summary Limited mouth opening is a common health problem that interferes with eating, makes examination of the oral cavity difficult, and may increase the mortality rate during emergency intubation. Here we introduce a disease designated as masticatory muscle tendon-aponeurosis hyperplasia, which is a new clinical condition of limited mouth opening. Most oral surgeons and dentists are still unaware of this disease condition, thus increasing the risk of incorrect diagnosis as some other disease, such as temporomandibular joint disorder. We will review the clinical features, epidemiology, pathophysiology, etiology, diagnosis, treatment, and prognosis of this disease and also appraise the literature available on the subject.

A 28-year-old man visited our hospital with the chief complaint of trismus. Computed tomography revealed a well-defined, soft tissue tumor, 66 × 45 × 21 mm, with a distinct boundary in the inner region of the zygomatic arch. The mass contained various sizes of bone-like hard tissue, some of which adhered to the right coronoid process. A contrast-enhanced magnetic resonance image showed that the mass was composed mainly of adipose tissue. Tumorectomy was performed, and the histopathological diagnosis was osteolipoma. At 2-year follow-up, mouth opening had increased from 31 mm to 50 mm. (J Oral Sci 58, 141-144, 2016).

Certain patients with facial deformities require superior repositioning of the maxilla via Le Fort I osteotomy; however, the magnitude of superior repositioning of the maxilla is often less than expected. In this study, the correlation between the accuracy of superior repositioning of the maxilla and the anatomical form of the maxillary posterior region was examined. Seventy-five patients who underwent Le Fort I osteotomy without forward movement of the maxilla but with superior repositioning of the maxilla were included in this study. The bone volume around the descending palatine artery (DPA), the angle of the junction between the pterygoid process and the tuberosity, and the distance between the upper second molar and the pterygoid process were measured via three-dimensional analysis. A significant negative correlation (r = −0.566) was found between the bone volume around the DPA and the ratio of repositioning (actual movement divided by expected movement). It is possible that the superior repositioning of the maxilla expected prior to surgery was not sufficiently attained because of the large volume of bone around the DPA. The results of this study show that in some patients, superior repositioning was not achieved at the expected level because of bone interference attributable to the anatomical form of the maxillary posterior region.

This study included 30 patients (17 males and 13 females; mean age, 73.7 ± 13.1 years) who were diagnosed with dehydration based on vital signs, skin symptoms, and blood test findings by emergency medicine physicians. First, the attending physician of our department measured oral mucosal dryness. Subsequently, the emergency medicine physician blindly divided the severity of dehydration into three stages according to clinical findings and blood test results. In this study, the oral moisture‐checking device (Mucus®; Life Co., Ltd., Saitama, Japan) was used to measure the oral mucosal dryness. We examined the oral moisture level for each dehydration severity level and the correlations of each severity level of dehydration with the measured values. Spearman's correlation coefficient (Medcalc version 11.3 for Windows) was used for statistical analysis. P

Background. Acquired hemophilia A (AHA) is a rare disorder which results from the presence of autoantibodies against blood coagulation factor VIII. The initial diagnosis is based on the detection of an isolated prolongation of the activated partial thromboplastin time (aPTT) with negative personal and family history of bleeding disorder. Definitive diagnosis is the identification of reduced FVIII levels with evidence of FVIII neutralizing activity. Case report. We report a case of a 93-year-old female who was diagnosed as AHA after tooth extraction at her home clinic. Prolongation of aPTT and a reduction in factor VIII activity levels were observed with the presence of factor VIII inhibitor. AHA condition is mild. However, acute subdural hematoma of this patient occurred due to an unexpected accident in our hospital. Hematoma was gradually increased and the patient died 13 days after admission. Discussion. Although AHA is mild, intracranial bleeding is a life-threatening condition. We also should pay attention to the presence of AHA patients when we extract teeth.

Intraductal carcinoma of the salivary gland is a rare, indolent neoplasm characterized by intraductal malignant cell proliferation but lacking invasiveness, in contrast to conventional salivary duct carcinoma, a clinically aggressive neoplasm with invasive characteristics. The tumor affects the major salivary glands much more frequently than the minor salivary glands. This report describes an extremely rare intraductal carcinoma arising from the buccal mucosa in a 61-year-old man who presented with a painless mass in the left buccal mucosa, which he had had for 1 month. A biopsy of the tumor indicated it was most likely an adenocarcinoma, but accurate preoperative diagnosis was difficult. The tumor was completely removed, along with sufficient margins. Histological examination revealed that the lesion was composed of proliferating epithelial cells surrounded by an intact myoepithelial layer, with no evidence of invasion. The final diagnosis was intraductal carcinoma of the salivary gland. No recurrence has been observed for over 3 years. In conclusion, the difficulty in preoperatively diagnosing this rare entity suggests that complete surgical excision with sufficient margins remains the best treatment option.