SP15. Arch Bars Versus IMF Screws: A Comparison of Outcomes

PURPOSE: Closed reduction of mandible fractures may be achieved through a variety of maxillomandibular fixation (MMF) approaches. Current literature offers little insight into best practices, and choice of MMF is often left to surgeon preference. This study aims to compare the outcomes of arch bars versus intermaxillary fixation (IMF) screws for closed reduction of mandible fractures. METHODS: A retrospective chart review was conducted on patients who underwent treatment of mandible fractures via MMF with arch bars or IMF screws at a single institution between 2009 and 2024. Patients with concurrent maxillary fractures were excluded. Patient demographics, MMF treatment course, and postoperative outcomes were analyzed. Student’s t-test and Fisher’s exact test were used for continuous and categorical variables, respectively (significance p<0.05). Data is reported as arch bars vs IMF screws, and continuous data are reported as a mean and standard deviation (SD). RESULTS: A total of 256 patients underwent MMF via arch bars (69%) or IMF screws (31%). Groups were comparable with respect to gender (87% vs 89% male, p=0.8), recreational drug use (35% vs 46%, p=0.14), and number of mandible fractures (1.8 SD 0.5 vs 1.6 SD 0.6, p=0.13). Tobacco use was more common among patients receiving IMF screws (56% vs. 71%, p=0.038). Patients received IMF screws later than arch bars (2.8 SD 3.7 vs. 4.5 SD 7.7 days after injury, p=0.032). IMF screws provided a shorter operative time than arch bars (80 SD 34 vs. 49 SD 65 min, p<0.0001). Of patients followed to arch bar or IMF screw removal, length of follow-up was 151 SD 412 and 98 SD 135 days, respectively (p=0.4), with similar time in MMF (36 SD 21 vs 32 SD 17 days, p=0.3) and time with hardware (100 SD 193 vs 91 SD 132 days, p=0.8). More patients self-released MMF in the IMF screw group (15% vs 24%), though this was nonsignificant (p=0.2). Patients self-removed 4% of arch bars and no IMF screws (p=1). IMF screws were more frequently removed in clinic (44%) compared with arch bars (9%, p<0.001). Groups had similar rates of infection (7% vs 6%, p=1), hardware loosening (7%, p=1), mucosal injury/overgrowth (14% vs 19%, p=0.5), return to ED for pain (23% vs 28%, p=0.6), hardware loosening (17% vs 13%, p=0.8), malocclusion after removal (10% vs 11%, 0.8), and exchange for other fixation methods (5% vs 7%, p=0.5). Neither tobacco use nor drug use were associated with infection (p=0.10, p=0.3) or malocclusion (p=0.3, p=0.8). Tobacco use and drug use were positively associated with return to the ED for pain (p=0.018 and p=0.011, respectively) but MMF modality did not influence this (p=0.4 and p=0.8, respectively). CONCLUSION: IMF screws provide a shorter operative time, ease of awake removal, and noninferior outcomes compared with arch bars.