Author(s)
Alan W. Johnson, MD MS
Affiliation(s)
Altru Health System
Abstract:
Educational Objective: At the conclusion of this presentation, the participants should be able to 1) understand how to harness the apical embrasure between teeth to secure noninvasive maxillomandibular fixation (MMF); 2) describe the development process of a new technology from initial design sketch, through engineering design, prototyping, cadaver testing, and ultimately to feasibility clinical trial validation; and 3) contrast dental occlusion ties from Erich arch bars and screw based and "hybrid" MMF techniques. Objectives: Maxillomandibular fixation (MMF) establishes dental occlusion to treat mandible and maxilla fractures. For decades, Erich arch bars have been the standard to establish MMF. While reliable, the approach risks sharps injury, consumes operating room time, and inflicts gingival trauma. Newer technologies including screw based techniques and hybrid techniques have improved MMF by reducing sharps injuries and operating room time, but risk injury to tooth roots, nerves, and gingiva. A need remains for an efficient, safe, and noninvasive MMF solution. Study Design: Prospective, non-blinded, human feasibility clinical trial. Methods: An iterative prototyping process was used to invent dental occlusion ties. Development included 3D printing, cadaver prototype testing, human apical embrasure dimensioning, and ultimately nonsignificant risk human clinical trial testing. In the IRB approved feasibility clinical trial, the devices were applied to mandible and maxilla fracture candidates with fractures amenable to intraoperative MMF with open reduction/internal fixation. The ties were removed prior to extubation. Pre-teens, comminuted fracture patients, and patients requiring postoperative MMF were excluded. Results: Fully optimized and manufactured prototypes secured MMF successfully in management of unilateral and bilateral mandible fractures as well as displaced maxilla fractures. All patients reported correction of fracture related malocclusion. Application times were consistently 12-15 minutes for a single surgeon to achieve MMF. Patients incurred negligible gingival trauma from the technology as the ties require no screw or wire penetration for application. Conclusions: Dental occlusion ties offer a noninvasive solution featuring operating room time efficiency, minimized sharps risk, and less bony and soft tissue trauma than current commercialized solutions.