MRI Changes in the Temporomandibular Joint after Mandibular Advancement.

PURPOSE: Esthetic dental and skeletal component correction can affect the temporomandibular joint (TMJ). Arthrogenic TMJ dysfunction can be present in the joint at the outset or it can develop during the treatment or later. The aim of the present study was to examine the changes found on magnetic resonance imaging (MRI) studies of the TMJ in patients with skeletal Class II malocclusion who had undergone combined orthodontic and bilateral sagittal split ramus osteotomy (BSSRO) advancement. Our objective was to measure the changes in the disc position, condylar translation, secondary bony changes, and joint effusion on MRI before and after treatment. MATERIALS AND METHODS: An analytical, single-surgeon, single-institution, retrospective radiological (MRI) study was designed. We included patients who had undergone combined orthodontic and BSSRO advancement from 2011 to 2018. All 36 patients were examined using a 1.5-Tesla MRI unit (Siemens Symphony, Erlangen, Germany) with a 6 × 8-cm diameter surface coil, which allowed for simultaneous imaging of both TMJs. RESULTS: Analysis using the Wilcoxon signed rank test revealed statistically significant differences in the pre- and post-treatment groups in the changes in the position of the disc from anterior disc displacement with reduction (ADDWR) to the normal position (P = .008), condylar translation from excessive to normal (P = .046), and an increase in secondary bony changes (P = .005). CONCLUSIONS: Combined orthodontic and orthognathic movement in the treatment of skeletal Class II malocclusion can increase secondary bony changes, improve the disc position in ADDWR cases, and control excessive translation of the TMJ. No improvement was noted in the position of the disc in those with anterior disc displacement without reduction, hypomobility and joint effusion.

Radiological evaluation of sphenozygomatic suture fixation for restoration of orbital volume: A retrospective study.

PURPOSE: Lateral displacement of fracture zygomaticomaxillary complex (ZMC) can cause significant increase in orbital volume leading to enophthalmos. The aim of this study was to radiologically evaluate the efficacy of sphenozygomatic (SZ) suture fixation for restoration of orbital volume after elevation of the temporalis in cases of fracture ZMC where the fixation of zygomatic arch (ZA) was deemed necessary through latero-posterior approach. MATERIALS & METHODS: 43 operated cases of fracture ZMC using 4-point fixation were divided into two groups. Group I (n = 24) cases had undergone reduction and fixation of SZ suture as fourth point of fixation by elevating temporalis muscle using hemicoronal approach. Group II (n = 19) cases had undergone reduction and fixation of Infraorbital (IO) rim as fourth point of fixation using preseptal transconjunctival approach. Both the groups were analyzed separately and compared for restoring the increased orbital volume on CT. RESULTS: Difference in the pre-surgical orbital volume of both the groups was found to be statistically insignificant [p = .678]. In group I, the average bony orbital volume significantly reduced by 3.6 cc from 25.5 cc to 21.9 cc [p = .000] post-surgically. In group II, the average bony orbital volume reduced by 1.5 cc from 25.6 cc to 24.1 cc post-surgically There was a significant difference in the reduction of the increased orbital volume among the 2 groups (Group I: 3.6 cc, group II: 1.5 cc). The amount of reduction was more and statistically significant [p = .000] in the group I than group II. CONCLUSION: SZ suture fixation is reliable in reducing fractures ZMC and restoring the increased orbital volume where the fixation of zygomatic arch (ZA) was deemed necessary through latero-posterior approach.

Is Delayed Release of Superior Oblique Muscle Entrapment in Orbital Roof Fracture Worth Correcting?

Acquired Brown's syndrome is a rare entity. Delay in treatment can cause fibrosis or scarring with questionable prognosis of vertical diplopia. To the best of the knowledge of the authors the present case of 22-year-old male is the first in existing literature where delayed release of superior oblique muscle entrapment in orbital roof fracture was found to be an effective technique.

Sagittal split ramus osteotomy for aneurysmal bone cyst of the mandibular condyle.

Aneurysmal bone cyst is a benign pseudocystic osseous lesion characterized by a fibrous connective tissue stroma with cellular fibrous tissue, multinucleated giant cells, and large blood-filled spaces with no endothelial lining. The entity is uncommon in facial bones, and it rarely involves the mandibular condyle. Resection of the lesion is the most accepted treatment. The present case is the 11th reported case of aneurysmal bone cyst of the mandibular condyle in the existing literature and the first where, rather than using conventional extra oral approach, sagittal split ramus osteotomy was used to excise the lesion successfully with no recurrence after 3 years of follow-up.