Risk Factors for Hardware Removal Following Bimaxillary Surgery: A National Database Analysis

Abstract

Orthognathic surgery typically relies on the rigid fixation of fracture fragments using metal hardware. Though hardware is usually intended to be implanted permanently, the removal of hardware (ROH) is sometimes indicated for a variety of reasons. The authors sought to identify risk factors for ROH following orthognathic surgery. The authors conducted a retrospective analysis of the Merative MarketScan Research Databases, 2007–2021 using Current Procedural Terminology (CPT) and International Classification of Disease (ICD-9 and ICD-10) codes to identify patients who underwent an index Le Fort 1 osteotomy and bilateral sagittal split osteotomy operation on the same day. Statistical analysis involved χ2, Shapiro-Wilk, Wilcoxon-Mann-Whitney, Poisson regression, and multivariable logistic regression tests. 4698 patients met the inclusion criteria. The mean age at surgery was 25 years, and 57% were female. ROH occurred in 5.9% of patients. The mean time to hardware removal was 190.5±172.4 days. In a multivariate logistic regression, increased odds of ROH were associated with older patient age [OR: 1.02 (1.01–1.03), P=0.046], sleep apnea [OR: 1.62 (1.13–2.32), P=0.018], and craniofacial syndrome and/or cleft diagnoses [OR: 1.88 (1.14-2.55), P<0.001]. In the same model, postoperative oral antibiotic prophylaxis was not associated with ROH (P=0.494). The incidence of all-cause complications [IRR: 1.03 (1.01–1.05), P<0.001] rose over the study period, while the incidence of ROH did not change significantly (P=0.281). Patients at elevated risk should be counseled on the increased possibility of a second operation for ROH before having orthognathic surgery to ensure expectations and health care utilization decisions align with the evidence.