Evaluation of the mandibular ramus fracture line after sagittal split ramus osteotomy using 3-dimensional computed tomography.

PURPOSE: The true fracture line on the mandibular ramus after sagittal split ramus osteotomy cannot be observed using conventional x-ray techniques such as an orthopantomography. The aim of this study was to observe the fracture lines on the mandibular ramus after sagittal split ramus osteotomy by 3-dimensional computed tomography. PATIENTS AND METHODS: The subjects of this study were 30 patients with mandibular prognathism (7 men and 23 women). Their ages ranged from 17 to 45 years (mean age, 24 years). Osteotomy was performed by 3 techniques--the short medial cut, the lateral cut at the mandibular angle, and the connected cut. Sixty mandibular splits were evaluated by 3-dimensional computed tomography 1 to 2 weeks postoperatively. RESULTS: The mandibular ramus was fractured at 3 sites--the lingual surface, the posterior border, and the buccal surface. No fracture lines through the mandibular canal were observed. In relation to the 3 types of lateral bone cut end (A, lingual surface; B, inferior border; C, buccal surface) and the 3 fracture sites, 36 of the 37 lingual surface fractures were type A, 12 of the 14 posterior border fractures were type B, and 9 of the 9 buccal surface fractures were type C. CONCLUSION: A desirable splitting pattern occurred when a short lingual cut just above the lingula and a lateral bone cut of the mandibular angle were made, extending to the inside through the inferior border of the mandible. These observations also proved that the split patterns of the mandibular ramus could be controlled by the position of the lateral bone cut end.

Scar due to skin incision for screw fixation through the transbuccal approach after sagittal split ramus osteotomy.

Most rigid fixation techniques after sagittal split ramus osteotomies of the mandible involve the transbuccal approach. A skin incision in the cheek carries with it possible undesirable sequelae, such as noticeable scarring. The aim of this study was to investigate whether there is scarring in the face after this technique. For screw insertion, a 5-mm stab incision was performed on 40 Japanese patients (20 men and 20 women) with class III occlusion. After surgery, gross examination (via the naked eyes) of the skin incision was performed monthly for 1 year by the same oral surgeon. In all cases, the skin incision had disappeared by 1 year after the surgery.

Impact of inhaled ciclesonide on asymptomatic or mild COVID-19: A randomized trial.

The aim of this study was to determine the efficacy and safety of ciclesonide in the treatment of novel coronavirus disease 2019 (COVID-19) as gauged by pneumonia progression. This multi-center, open-label randomized trial was conducted with patients recruited from 22 hospitals across Japan. Participants were patients admitted with mild or asymptomatic COVID-19 without signs of pneumonia on chest X-rays. Asymptomatic participants were diagnosed after identification through contact tracing. Trial participants were randomized to either the ciclesonide or control arm. Participants in the treatment arm were administered 400 µg of ciclesonide three times a day over seven consecutive days. The primary endpoint was exacerbated pneumonia within seven days. Secondary outcomes were changes in clinical findings, laboratory findings, and changes over time in the amount of the viral genome. In the treatment group, 16 patients (39.0%) were classified as having exacerbated pneumonia compared to 9 (18.8%) in the control group. The risk ratio (RR) was 2.08 (95% confidence interval (CI): 1.15-3.75), indicating a worsening of pneumonia in the ciclesonide group. Significant differences were noted in participants with a fever on admission (RR: 2.62, 90% CI: 1.17-5.85, 95% CI: 1.00-6.82) and individuals 60 years of age or older (RR: 8.80, 90% CI: 1.76-44.06, 95% CI: 1.29-59.99). The current results indicated that ciclesonide exacerbates signs of pneumonia on images in individuals with mild or asymptomatic symptoms of COVID-19 without worsening clinical symptoms.

Periosteal reflection on the medial approach to the mandibular ramus in sagittal split ramus osteotomy.

We describe the modified medial opening to avoid blind procedures and to ensure periosteal dissection. The mucosal incision started behind the second molar and then wings laterally and forward at the lateral aspect. The medial subperiosteal dissection begins at the lingual border of the retromolar triangle. Minimal medial subperiosteal tunneling is performed only to identify the lingula. A medial osteotomy is performed above and 5 to 6 mm posterior to the lingula.

Screening for Gaucher Disease Using Dried Blood Spot Tests: A Japanese Multicenter, Cross-sectional Survey.

Objective For patients with Gaucher disease (GD), a rare, inherited lysosomal storage disease, obtaining a definitive diagnosis is currently time-consuming and costly. A simplified screening method to measure the glucocerebrosidase (GBA) activity using dried blood spots (DBS) on filter paper has recently been developed. Using this newly developed screening method, we evaluated real-world GD screening in patients suspected of having GD. Methods This multicenter, cross-sectional, observational study with a diagnostic intervention component evaluated real-world screening in patients suspected of having GD based on their clinical symptoms and a platelet count <120,000/µL. The endpoint was the number of patients with low GBA activity determined using DBS. Results In 994 patients who underwent initial DBS screening, 77 had low GBA activity. The assay was not repeated in 1 patient who was diagnosed as having a high possibility of GD due to clinical symptoms, and a further 21 patients completed the study without undergoing the second assay. Of the remaining 55 patients who had 2 DBS assays performed, 11 had a low GBA activity in both assays. Overall, DBS screening identified 12 (1.2%) patients with a low GBA activity, a proportion consistent with prior screening studies. Conclusion These results suggest that the simplified DBS method was less burdensome to patients, was easily utilized by many physicians, and could be a useful first-tier screening assay for GD prior to initiating burdensome genetic testing.

Accuracy of predicting the pharyngeal airway space on the cephalogram after mandibular setback surgery.

PURPOSE: The aim of the present study was to evaluate the accuracy of a formula predicting the change of pharyngeal airway space (PAS) on the cephalogram after mandibular setback surgery. PATIENTS AND METHODS: Twenty-nine female adults with mandibular prognathism underwent surgery by bilateral sagittal split ramus osteotomy. The postoperative anteroposterior (A-P) PAS dimension was calculated from the change of C3-Me (distance between the anteroinferior point of the third cervical vertebra and menton) using 2 cephalograms taken before treatment and at 1 year after surgery. The regression equation used was y = -21.105 + 0.402x (y: PAS; x: C3-Me; r = 0.854). RESULTS: The predicted and measured values were nearly same on average, and the difference between both ranged within +/-1.5 mm for each case individually. CONCLUSION: This study suggested that the postoperative A-P PAS dimension can be predicted from the change in C3-Me, matching the amount of the mandibular setback.

[Alveolar rhabdomyosarcoma of unknown origin mimicking acute leukemia at the initial presentation].

A 14-year-old boy presented with a short history of general fatigue. Laboratory examination of the peripheral blood revealed white blood cells 11,300/microl, hemoglobin 10.4 g/dl, platelets 45,000/microl, fibrinogen < 50 mg/dl, fibrin/fibrinogen degradation products 536 microg/ml and lactate dehydrogenase 1,684 U/l. A bone marrow aspirate contained 89.6% of undifferentiated tumor cells. A hematological malignancy was suspected and the patient was treated with idarubicin and cytarabine. However, further examination revealed that tumor cells were positive for CD56 and lacked lineage markers of lymphoid or myeloid cells. They were positive for PAS, HHF35 and desmin, and negative for MPO. Reverse transcriptase polymerase chain reaction demonstrated PAX3/FKHR fusion transcripts, confirming the diagnosis of alveolar rhabdomyosarcoma. Radiological examination revealed only one enlarged lymph node being 1.5 cm in diameter at the paraaortic region in the abdomen, and failed to find a primary tumor. After three courses of chemotherapy containing etoposide, cyclophosphamide, pirarubicin, cisplatin and vincristine, tumor cells were eradicated from the bone marrow. The patient received an allogeneic bone marrow transplantation eight months after diagnosis, although he died of hepatic veno-occlusive disease on day 21. Alveolar rhabdomyosarcoma often develops in older children and younger adults, and its bone marrow infiltration may mimic acute leukemia.

Tooth exfoliation and necrosis of the crestal bone caused by the use of formocresol.

A 68-year-old woman received a formocresol pulpectomy of the right lower lateral incisor. The temporary restoration was lost within hours. The next day, the patient suffered continuous pain, the gingiva sloughed, and the alveolar bone was exposed. Four days after treatment, the patient complained of moderate pain. Six days after the pulpectomy, the tooth spontaneously exfoliated. At this time she was referred to our hospital. The clinical diagnosis was chronic alveolitis. Treatment consisted of irrigation of the area. Three weeks after the pulpectomy, the dull pain had subsided, but the alveolar bone of the area showed increased mobility. Five weeks after the pulpectomy, the mobility of the alveolar bone was more significant and a sequestrectomy was performed with the patient under local anesthesia. The sequestrum of necrotic bone was approximately 10 x 5 x 5 mm in size. The patient has been symptom-free for 2 years since the sequestrectomy.

The stability of an alar cinch suture after Le Fort I and mandibular osteotomies in Japanese patients with Class III malocclusions.

We previously reported a modified technique for the placement of symmetrical cinch sutures after switching from a nasal to an oral endotracheal tube. We undertook a study to assess the effectiveness of our technique and the stability of changes in the nasolabial morphology after bimaxillary surgery. The study group comprised 30 patients aged 17-36 years who had skeletal Class III malocclusion. All patients had bimaxillary surgery with an alar base cinch suture and V-Y closure. The nasal region was measured directly or on cephalograms before, and 1 week and 1 year after operation. The suture did not alter the width of the alar base, but the nasolabial angle and projection of the tip increased significantly. The length of the upper lip did not change significantly.

Computed tomography morphology of the mandibular ramus in prognathism: effect on the medial osteotomy of the sagittal split ramus osteotomy.

PURPOSE: The purpose of this study was to investigate the distribution of cancellous bone relative to performance of the medial osteotomy of a sagittal split ramus osteotomy using computed tomography scanning. PATIENTS AND METHODS: Skeletal Class III patients consisted of 11 males and 22 females with a mean age of 23 years. The control patients without dentofacial deformity consisted of 10 males and 20 females with a mean age of 25 years. Scans were taken parallel to the mandibular occlusal plane, and morphologic measurements, including distribution of cancellous bone, were obtained. RESULTS: Compared with the control patients, the mandibular ramus of Class III patients was thinner with a more complicated and varied cancellous bone pattern, such as separate regions of cancellous bone and lack of cancellous bone posterior and anterior to the mandibular foramen. CONCLUSIONS: It was apparent that the safest region in which to establish the medial osteotomy line was just superior and 5 to 6 mm posterior to the lingula, directing the line slightly inferior.

Ultrastructural study of synovitis induced by trauma to the rat temporomandibular joint (TMJ).

BACKGROUND: Electron microscopy was used to examine the histologic effect of trauma on the rat temporomandibular joint synovial membrane. METHODS: Trauma to the TMJ in male Wister rats (100-200 g) was introduced through repeated forced condylar hypermobility. Ultrastructural observations were made 5 days and 6 weeks after the trauma. RESULTS: The early response of the synovial membrane was synovial hyperplasia, type A synovial cell loss, dilation of the r-ER in the type B synovial cells and fibrin deposition on the synovial surfaces. The late response included degeneration of synovial cells with swollen mitochondria and cell projections, and cell fragmentation. Large amount of fibrin deposition on opposing surface layers was also noticed. CONCLUSION: The type A cell loss and fibrin deposition followed by the occurrence of fibrinous materials at opposing surface layers of the synovial membrane suggest that traumatic synovitis causes synovial adhesions.