Intra-Operative Temporary Rigid Fixation of Mandible Fractures Allows Dynamic Occlusal Assessment and Makes Maxillomandibular Fixation Unnecessary
Mark C. Martin, MD, DMD, FRCSC, Gustavo R. Machado, MD, David C. Cho, MD, Brinda Thimmappa, MD, Grigoriy Arutyunyan, BS.
Loma Linda University Medical Center, Loma Linda, CA, USA.
Purpose: Maxillomandibular fixation (MMF) is an imperfect method to secure the occlusion in simple mandible fractures. MMF is time consuming procedure that places the surgeon at risk of blood borne disease transmission. The aim of this retrospective clinical study is to evaluate clinical and radiographic outcomes in a series of 100 consecutive mandibular fractures treated with a specific method of intra-operative temporary rigid fixation (TRF) and dynamic occlusal assessment followed by definitive rigid fixation eliminating MMF.
Methods: A single-surgeon series of one hundred consecutive non-comminuted mandible fractures treated with TRF from June 2006 to November 2008 from two Level 1 Trauma Centers. Contraindications for the TRF technique were defined as: 1. Patients with other injuries requiring application of MMF or 2. Patient refusal of the technique during informed consent procedures. Patient demographics, operative records, pre and post-reduction CT scans, and occlusal outcomes were examined and tabulated.
Intra-oral incisions are used to expose and debride the fracture. Temporary rigid fixation is applied as the fragments are manipulated into anatomic reduction using a mini external fixator or a special bone clamp depending on the anatomic region. A detailed, dynamic occlusal assessment is performed and if the pre-morbid occlusion has been restored then final rigid fixation is applied and the TRF removed.
Results: A consecutive series of 100 fractures were treated with the TRF technique. The patient demographics, etiology, fracture distribution, and complications were tabulated (Table 1). The overall complication rate was 12.5% (8 patients), infection in 8% (5 patients), followed by one case (1.5%) of each: hardware failure, delayed union and hardware exposure. The TRF technique was successful in establishing a stable maximal intercuspal position (MIP) without prematurity, open bites, or new cross bites in all patients. Pre-morbid occlusion was accomplished in 100% of patients as determined in the post-operative clinic. No patient required revision of fixation for malreduction and/or malocclusion. Postoperative CT scans were reviewed by four facial trauma surgeons who graded the fracture reductions on a five point Likert scale. Reductions were graded as “Excellent” for 96%, “Good” for 3%, “Fair” or “Poor” for 1% based on the CT scans.
Conclusion: The TRF technique offers benefits over the traditional method of MMF to secure the occlusion: 1. Eliminating MMF shortens the procedure 2. Wires which are a health hazard to surgeons are dispensed with 3. TRF allows the dynamic evaluation of intercuspation, excursive relations, and protrusive relations before fixation 4. Iatrogenic lingual-tilt in the coronal plane and lingual-splay in the axial plane caused by MMF is avoided. Finally, our technique is suitable for practitioners of all experience levels since if a pre-morbid occlusion is not easily confirmed once TRF is applied subsequent conversion to an MMF-established jaw relation is simple, although we have not encountered this problem in treating one hundred consecutive fractures.
|Patients Demographics (n=64)|
|Mean Age (y)||30 years|
|Operating Time Per Fracture||72 minutes|
Table 1. Key Patient Demographics