RESUMEN
PURPOSE: Intraoral vertical ramus osteotomy (IVRO) has, traditionally, been accomplished without internal fixation, necessitating a period of maxillomandibular fixation (MMF). With advances in instrumentation, internal fixation of IVRO is feasible, obviating the need for MMF. The purpose is to investigate the effects of transoral internal fixation on the prevalence of third division trigeminal nerve (CNV3) injury, temporomandibular joint (TMJ) arthralgia, and surgical site bleeding following IVRO. MATERIALS AND METHODS: A retrospective study was conducted on patients who underwent IVRO at Vanderbilt University Medical Center between January 2017 and December 2020. The primary predictor variable was fixation status-internal fixation versus MMF. The primary outcome variable was postoperative CNV3 neurosensory disturbance. The secondary outcome variables were TMJ arthralgia and surgical site bleeding. Statistical analysis included Fisher's exact test and McNemar's Chi-squared test. RESULTS: Seventy two subjects (59 IVROs without internal fixation and 65 IVROs with internal fixation) were studied. The frequency of CNV3 neurosensory deficit was 0% in the IVRO without internal fixation group and 3.1% in the IVRO with internal fixation group (P = .49). Within group analysis showed a decreased frequency of postoperative TMJ arthralgia compared to preoperative records in both groups (IVRO without internal fixation group, P = .04 and IVRO with internal fixation group, P = .004). The frequency of active surgical site bleeding controlled with local measures was 1.7% in the IVRO without internal fixation group and 3.1% in the IVRO with internal fixation group (P = 1). CONCLUSION: Internal fixation of IVRO is associated with low incidence of neurosensory deficit, TMJ arthralgia, and active surgical site bleeding.
Asunto(s)
Osteotomía Sagital de Rama Mandibular , Prognatismo , Humanos , Osteotomía Sagital de Rama Mandibular/efectos adversos , Mandíbula/cirugía , Estudios Retrospectivos , Prognatismo/cirugía , Articulación Temporomandibular/cirugía , Técnicas de Fijación de Maxilares , Pérdida de Sangre QuirúrgicaRESUMEN
PURPOSE: Several studies have investigated risk factors of unfavorable splits associated with sagittal split osteotomies but yielded conflicting information. The purpose of this study is to estimate the frequency of and identify factors associated with unfavorable splits during sagittal split osteotomies (SSOs). MATERIAL AND METHODS: A retrospective cohort study was conducted on patients who underwent orthognathic surgery, including SSOs at our institution from January 2010 to October 2016. The independent variables were mandibular third molar (M3) status, age, gender, and preoperative dentofacial diagnosis. The outcome variable was the effectiveness of the sagittal split resulting in either favorable or an unfavorable split. Data analyses were performed using logistic regression models except in the case of small sample sizes of preoperative dentofacial diagnoses for which the Fisher's exact test was used. RESULTS: A total of 888 patients with an average age of 24.97 ± 5.09 years underwent 1,776 SSOs. Sixteen (0.90%) unilateral unfavorable splits occurred. Unfavorable splits were less common in patients with an M3 present than in patients with the M3 absent. Having an M3 present reduced the chance of an unfavorable split by 69%, adjusted for age and gender; OR (95% CI) = 0.308 (0.103, 0.919); P = .035. The odds of having an unfavorable split were increased by 8.8% for every year of age increase; adjusted OR (95% CI) = 1.088 (1.004, 1.178); P = .038. Based on this estimation, a 45-year-old is 2.3 times more likely to have an unfavorable split compared to a 35-year-old (95% CI:1.041, 5.146), and is 5.4 times more likely to have an unfavorable split compared to a 25-year-old (95% CI:1.083, 26.48). CONCLUSIONS: The presence of a mandibular third molar (M3) was associated with a decreased risk of an unfavorable split, independent of age and gender. There was a significant association between increased age and the incidence of an unfavorable split.