Remodeling of the Temporomandibular Joint After Mandibular Setback Surgery: A 3D Cephalometric Analysis.

BACKGROUND: Condylar adaptations following orthognathic surgery remain an area of interest. Prior studies do not use 3-dimensional imaging modalities and lack standardization in the choice of osteotomy and movement when assessing condylar changes. PURPOSE: The purpose of this study was to use 3-dimensional cephalometry to measure the association between osteotomy type (sagittal split osteotomy [SSO] vs vertical ramus osteotomy [VRO]) and changes in condylar volume and position. STUDY DESIGN, SETTING, AND SAMPLE: This is a retrospective cohort study from January 2021 through December 2022 of patients at Bellevue Hospital in New York City, New York who were treated with either SSO or VRO for the correction of Class III skeletal malocclusion. PREDICTOR/EXPOSURE/INDEPENDENT VARIABLE: The primary predictor was the type of mandibular osteotomy, sagittal split osteotomy, and vertical ramus osteotomy. MAIN OUTCOME VARIABLES: The primary outcomes were changes in condylar volume (change measured in mm3) and relative position (anterior-posterior change utilizing the Pullinger and Hollinder method). COVARIATES: Covariates included patient age, sex, setback magnitude, temporomandibular joint symptoms, and fixation method for SSO patients. ANALYSES: Univariate comparisons were performed between independent variables and study outcomes. Volume changes were compared within each predictor using paired t-tests. Position changes were compared within each predictor using χ2 tests. If there were multiple significant univariate predictors, multiple regression models were created to predict volume and position changes. A P < .05 value was considered statistically significant. RESULTS: The final sample comprised 30 condyles derived from 30 subjects. Mean age was 22.7 years (SD = 5.7) and mean setback was 3.9 mm (SD = 0.9). Twenty two condyles (73.3%) were subject to SSO with fixation, while the remaining 8 (26.7%) condyles were subject to intraoral VRO without fixation. When compared to VRO, condyles manipulated with SSO had greater volume loss (-177.2 vs -60.9 mm3; P = .03) and positional change (68.2 vs 12.5%; P < .01). Self-reported measures of postoperative pain, internal derangement, and myofascial symptoms were not significantly associated with either volume or positional changes. CONCLUSIONS AND RELEVANCE: The SSO resulted in greater postoperative condylar volume loss and positional changes. These volume and positional changes were not correlated with self-reported temporomandibular disorder symptoms.

Does Open Reduction and Internal Fixation Provide a Quality-of-Life Benefit Over Traditional Closed Reduction of Mandibular Condyle Fractures?

PURPOSE: This study sought to estimate patient-reported outcomes and compare quality-of-life (QOL) measures between patients electing for either open reduction internal fixation (ORIF) or closed reduction with intermaxillary fixation (CRIMF). PATIENTS AND METHODS: This was a retrospective cohort study of patients with unilateral condyle fractures who had undergone either ORIF or CRIMF at the New York University Tisch Hospital and Bellevue Hospital Center. The primary study predictor was treatment choice (ORIF or CRIMF). Other study predictors were patient age, gender, and the presence of any other coexisting facial fractures. The 9 study outcomes were derived from an 11-item postoperative QOL questionnaire evaluating self-reported perceptions of pain and function. Univariate comparisons and multivariate regression models were calculated. RESULTS: A total of 38 patients (21 CRIMF and 17 ORIF) comprised the study sample. All patients were eligible for either ORIF or CRIMF, and the choice of treatment was decided through shared decision making after a comprehensive discussion of risks and benefits. With respect to pain outcomes, patients who underwent ORIF reported lower overall pain scores at 2 weeks (P < .01) and 2 months (P = .01), less mastication pain at 3 months (P = .01), and a lower rate of persistent headaches after 6 weeks (P = .04). With respect to functional outcomes, patients who underwent ORIF reported better range of motion at 3 months (P = .01), less treatment-related weight loss (P = .01), and more ease when performing physical (P < .01) and work-related (P < .01) activities. In the multivariate regression models, ORIF was independently associated with decreased pain at 2 weeks (P < .01) and decreased difficulty in obtaining nutrition (P < .01), performing physical activities (P = .02), and performing work-related activities (P < .01). CONCLUSIONS: Patients who underwent ORIF appeared to experience subjective favorable pain and functional QOL outcomes. Given the clinical controversy, the choice of treatment should synthesize patient-reported outcomes and be approached through shared decision making.

Are Motorized Scooters Associated With More Severe Craniomaxillofacial Injuries?

PURPOSE: The purpose of the present study was to compare the severity of craniomaxillofacial injuries between accidents involving motorized and nonmotorized standup scooters. MATERIALS AND METHODS: This is a 20-year cross-sectional study of the National Electronic Injury Surveillance System. Injuries from powered and unpowered standup scooters were included in this study if they involved the head, face, eyeball, mouth, or ear. Study predictors were obtained from both patient and injury characteristics. The study outcome was the probability of hospital admission from the emergency department. A multiple logistic regression model was created to model the probability of admission using all significant univariate predictors. RESULTS: A total of 11,916 records were included in the present study, of which 9.5% involved motorized scooters. The proportion of motorized injuries more than tripled from 2014 (5.8%) to 2018 (22.1%). Motorized injuries occurred more often in older individuals (24.0 vs 8.5 years; P < .01). A greater proportion of motorized injuries involved the head (55.0 vs 36.9%; P < .01) and resulted in concussion (11.5 vs 5.6%; P < .01), fractures (6.7 vs 2.0%; P < .01), and other nonspecified internal organ injuries (31.1 vs 19.6%; P < .01). Motorized scooter injuries had more than triple the admission rate compared to nonmotorized injuries (13.9 vs 3.7%; P < .01). After controlling for potential confounders, injuries from motorized scooters still had double the odds of hospital admission (odds ratio, 2.03; P < .01). CONCLUSIONS: Motorized standup scooters appear to cause more severe injuries than conventional nonmotorized scooters. The recent growth of rentable electric scooters may pose a future public health concern. Ride-sharing companies should ensure that customers are capable of safely and responsibly operating these vehicles.