Search

Peripheral ameloblastoma (PA) is an uncommon variant of ameloblastoma that occurs in extraosseous soft tissue. Our patient, a 10-year-old girl, was hospitalized with a mass in the anterior plate gingiva. The elastic hard mass was approximately 7 mm in length, the surface mucosa was normal, and no spontaneous or oppressive pain was present. Computed tomographic and panoramic X-ray examination revealed no infiltration into the anterior plate. First, we performed biopsy of the mass; pathologic study revealed that the tumor was a PA. The prognosis of patients with PA is generally good, but recurrence has been reported. In surgery, we resected the tumor with 5-mm margins, which included the periosteum. After surgery, no recurrence was observed, and the wound healed well. No evidence of recurrence was found at follow-up observation, but we plan to continue monitoring the patient carefully.

It is known that congenitally missing teeth can often cause differences in craniofacial morphology; however, there are few reported cases of orthognathic surgical treatment for these patients. Herein, the authors report a rare case of maxillary hypoplasia with congenital oligodontia treated by maxillary distraction osteogenesis with internal device. A 17-year-old male presenting with multiple tooth agenesis and maxillary recession was referred to our hospital for orthognathic surgical treatment. Preoperative simulation surgery was performed using Full-Color 3-dimensional salt model. After surgery, improvement in maxillary recession and occlusal stability was observed. This report demonstrates the advantages of the method used herein, which includes reduction in operating time with increase in the safety of the procedure.

Adult Cebpb KO mice incisors present amelogenin-positive epithelium pearls, enamel and dentin allopathic hyperplasia, fewer Sox2-positive cells in labial cervical loop epitheliums, and reduced Sox2 expression in enamel epithelial stem cells. Thus, Cebpb acts upstream of Sox2 to regulate stemness. In this study, Cebpb KO mice demonstrated cementum-like hard tissue in dental pulp, loss of polarity by ameloblasts, enamel matrix in ameloblastic layer, and increased expression of epithelial-mesenchymal transition (EMT) markers in a Cebpb knockdown mouse enamel epithelial stem cell line. Runx2 knockdown in the cell line presented a similar expression pattern. Therefore, the EMT enabled disengaged odontogenic epithelial stem cells to develop supernumerary teeth. Cebpb and Runx2 knockdown in the cell line revealed higher Biglycan and Decorin expression, and Decorin-positive staining in the periapical region, indicating their involvement in supernumerary tooth formation. Cebpb and Runx2 acted synergistically and played an important role in the formation of supernumerary teeth in adult incisors.

While the prevalence of supernumerary teeth (ST) is high in permanent dentition, the etiology of ST in humans remains unclear. However, multiple murine models of ST have elaborated on dated mechanisms traditionally ascribed to ST etiology: one involves the rescue of rudimental teeth, and the second considers the contribution of odontogenic epithelial stem cells. It remains unclear whether these mechanisms of ST formation in mice are applicable to humans. The third dentition is usually regressed apoptotic—that is, the teeth do not completely form in humans. Recently, it was suggested that ST result from the rescue of regression of the third dentition in humans. The present investigation evaluates the proportion of collected general ST cases that evinced a third dentition based on the clinical definition of ST derived from the third dentition. We also investigated the contribution of SOX2-positive odontogenic epithelial stem cells to ST formation in humans. We collected 215 general ST cases from 15,008 patients. We confirmed that the general characteristics of the collected ST cases were similar to the results from previous reports. Of the 215 cases, we narrowed our analysis to the 78 patients who had received a computed tomography scan. The frequency of ST considered to have been derived from the third dentition was 26 out of 78 cases. Evidence of a third dentition was especially apparent in the premolar region, was more common in men, and was more likely among patients with ≥3 ST. SOX2-positive odontogenic epithelial stem cells within the surrounding epithelial cells of developing ST were observed in non–third dentition cases and not in third dentition cases. In conclusion, the third dentition is the main cause of ST in humans. The odontogenic epithelial stem cells may contribute to ST formation in cases not caused by a third dentition.

OBJECTIVES The aim of this study was to examine the relationship between morphologic factors of mandibular protrusion patients and clinical indices of obstructive sleep apnea (OSA). METHODS Fifty-two Japanese patients divided into 2 groups: 1 jaw surgery group (30 patients) and 2 jaw surgery group (22 patients). Morphologic changes were studied using cephalograms taken before surgery and 1 year after surgery. Functional changes studied using impulse oscillometry and pulse oximetry during sleep, both of which are clinically useful measures in assessing OSA, taken before surgery and 1 year after surgery. RESULT Lower face cage area significantly decreased in 1 jaw group than in 2 jaw group patients. Positive significant correlation was found between changes in 3% oxygen desaturation index (ODI) and changes of tongue area and vertical position of the hyoid bone in 1 jaw surgery group. Multiple regression analysis indicates that tongue area and airway area were independently significant predictors of 3% ODI in 1 jaw group patients. CONCLUSION In 2 jaw surgery, maxillary surgery compensated for the effect of mandibular setback surgery. Mandibular setback surgery to mandibular protrusion patients was performed within the range of adequate movement distance, but precautions for risk of postoperative obstructive sleep apnea syndrome should be considered.

Robinow syndrome is very rare and is characterized by congenital anomalies of the head and neck. Symptoms occurring in the head and neck region include osteosclerosis of the skull, midface hypoplasia, cleft palate, and impacted teeth. There is no case report describing oral maxillofacial surgery in Robinow syndrome. We report the case of a 19-year-old female in whom a panoramic radiograph revealed a radiopaque lesion in the right maxillary molar region along with multiple impacted teeth, hypodontia, and retained deciduous teeth in her jaws. Impacted tooth was also present in the radiopaque lesion on the right maxilla. Computed tomography revealed a high-density area on the right maxilla, representing a lesion containing an impacted tooth. The general findings and the presence of impacted teeth indicated symptomatic disease, and biopsy examination confirmed an osteoma. After additional examinations, Robinow syndrome was diagnosed. Tooth extraction was performed under general anesthesia. About 8 months after operation, the wound showed epithelialization and osteoma-like tissue formation was confirmed in the extraction socket. We considered repeated observations to be necessary in this case because of the possibility of recurrence. It is necessary to be aware of the possible diagnosis of Robinow syndrome on the basis of intraoral symptoms after school age.

Bernard–Soulier syndrome is characterized by thrombocytopenia, giant platelets, and severe bleeding; although bleeding varies widely, it is usually evident from childhood and requires particular attention during surgeries. We extracted a fractured tooth and performed hemostasis management in a male patient with a Bernard–Soulier syndrome-related severe bleeding tendency after intracerebral hemorrhage. The preoperative platelet count was abnormally low (7 × 10 9 /L). Normal coagulability was observed. After intravenous hydrocortisone administration, he received 10 human leukocyte antigen-matched platelet units. The extraction sites were packed with gelatine sponges and a splint was used for hemostasis. Excellent hemostasis was achieved with minimal human leukocyte antigen-matched platelets.

Congenital thrombocytopenia is a rare, intractable hereditary disease characterized by thrombocytopenia and abnormalities of platelet function. In contrast, idiopathic thrombocytopenic purpura (ITP) is a more frequent thrombocytopenic disease. Furthermore, it is possible that chronic and refractory ITP include congenital thrombocytopenia. We describe a case in which we extracted a tooth and performed hemostasis in an 87-year-old man with a suspected congenital X-linked thrombocytopenia (XLT)-related severe bleeding tendency. XLT is very rare in congenital thrombocytopenia. The patient had a platelet count of 2.0 × 104/μL and received 20 units of platelet concentrate before and after the extraction in liaison with our hematology and oncology department. We have previously reported a model on hemostasis management and extraction of Bernard–Soulier Syndrome (BSS) patients with congenital thrombocytopenia. The extraction sites were packed with gelatin sponges, and sutured, then a splint was used for hemostasis. Excellent hemostasis was achieved with minimal required platelet infusion.

Adult Cebpb KO mice incisors present amelogenin-positive epithelium pearls, enamel and dentin allopathic hyperplasia, fewer Sox2-positive cells in labial cervical loop epitheliums, and reduced Sox2 expression in enamel epithelial stem cells. Thus, Cebpb acts upstream of Sox2 to regulate stemness. In this study, Cebpb KO mice demonstrated cementum-like hard tissue in dental pulp, loss of polarity by ameloblasts, enamel matrix in ameloblastic layer, and increased expression of epithelial-mesenchymal transition (EMT) markers in a Cebpb knockdown mouse enamel epithelial stem cell line. Runx2 knockdown in the cell line presented a similar expression pattern. Therefore, the EMT enabled disengaged odontogenic epithelial stem cells to develop supernumerary teeth. Cebpb and Runx2 knockdown in the cell line revealed higher Biglycan and Decorin expression, and Decorin-positive staining in the periapical region, indicating their involvement in supernumerary tooth formation. Cebpb and Runx2 acted synergistically and played an important role in the formation of supernumerary teeth in adult incisors.

Purpose: In this report, we had managed to perioperative of mandibular fractures in a patient with severe hyperthyroidism. Methods: A 26-year-old man required emergency admission to the hospital after having a fall and losing consciousness. A computed tomography (CT) scan revealed a fracture line in the mental region and both sides of the condyle. He had a previous history of hyperthyroidism and was prescribed thiamazole, propranolol hydrochloride, and potassium iodide, but he did not take medicine by self-judgement. His laboratory findings were as follows: FT3, 7.53[Formula: see text]pg/mL; FT4, 4.26[Formula: see text]ng/mL; and TSH, undetectable. Therefore, we planned for surgery immediately after his condition improved. We also postponed his maxilla-mandibular fixation (MMF) procedure because there was a probability that MMF procedure caused thyroid crisis. Result: Seventeen days after his injury, he had greatly reduced his risk of having thyroid crisis, he underwent open reduction of his mandibular fractures under general anesthesia. As perioperative management, the patient underwent an opening training and oral care before and after surgery in addition to thyroidal treatment. Conclusion: The procedures prevented adhesion of temporomandibular joint and recovered aperture size. Moreover, we diagnosed agranulocytosis from intraoral lesion and obtained good course in response to early.