Hybrid Arch Bars Reduce Placement Time and Glove Perforations Compared With Erich Arch Bars During the Application of Intermaxillary Fixation: A Randomized Controlled Trial

Abstract

The purpose of this study was to compare the time for placement and removal, the effect on the gingiva, and the operator safety of the Stryker Universal SMARTLock Hybrid MMF system (Stryker Craniomaxillofacial, Kalamazoo, MI) with traditional Erich arch bars. We designed a parallel-group, randomized controlled trial to compare the 2 types of arch bars. Patients with mandibular fractures presenting to our institution were enrolled in the study and randomized into 1 of 2 groups: the Erich arch bar group and the hybrid arch bar group. The primary outcome variable was arch bar placement time. Secondary outcomes were glove tears or penetrations during application, gingival appearance score at removal, loose hardware at removal, removal time, and glove tears or penetrations at removal. The groups were compared using t tests. We enrolled 90 patients in the study, with 43 randomized to the Erich arch bar group and 47 randomized to the hybrid arch bar group. The mean application time was 31.3±9.3minutes for Erich arch bars and 6.9±3.1minutes for hybrid arch bars (P<.0001). Significantly more glove tears or penetrations occurred during application in the Erich Arch Bar group (0.56±0.91 per application) than in the hybrid group (0.11±0.32 per application) (P=.0025). At removal, no difference in overall gingival appearance or amount of loose hardware was noted. The time for removal was significantly less for the hybrid arch bar group (10.5±5.1minutes vs 17.9±10.7minutes, P=.0007). Hybrid arch bars with bone-borne locking screws offer a number of advantages over traditional Erich arch bars and circumdental wires, including shorter placement and removal times and a greater margin of safety for the operating surgeon as shown by significantly fewer glove tears and penetrations.