Biomechanical evaluation of plating techniques for fixing mandibular angle fractures: the introduction of a new 3D plate approach.
ABSTRACT The aim of this study was to comparatively evaluate the use of a three-dimensional (3D) square-shaped plate for the treatment of mandibular angle fractures.
Synthetic mandible replicas were used to evaluate the effectiveness of the 3D square plate along with three other mandibular angle plating techniques. The plating techniques consisted of: (1) a 3D miniplate (2 x 2 holes, square, 2 mm); (2) a 3D miniplate (6 x 2 holes, curved, 2 mm); (3) two miniplates (four holes, straight, 2 mm and 1.6 mm); and (4) one single miniplate (four holes, straight, 2 mm). Each group was subjected to incisal and homolateral molar region loading by a tensile materials testing machine (Monsanto Tensometer 20). Load stiffness values and peak measurements of the fracture gap distraction at the superior aspect of the mandible were measured. The mean values (+/-standard deviation) were derived and compared using one-way analysis of variance, with statistical significance set at p < 0.05.
For homolateral molar loading, statistically significant differences existed within groups (p < 0.05). For incisal edge loading, no statistically significant differences were found for stiffness among the fixation methods tested. Gap distraction at the superior aspect of the mandible was limited for three of the groups tested.
Under the conditions tested, the 3D square plate system provided the most favorable mechanical behavior.
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ABSTRACT: PURPOSE: The purpose of this study was to review the literature regarding the evolution of current thoughts on fixation of mandibular angle fractures (MAFs). METHODS: An electronic search in PubMed was undertaken in August 2012. The titles and abstracts from these results were read to identify studies within the selection criteria. Eligibility criteria included studies from the last 30 years (from 1983 onwards) reporting clinical studies of MAFs. RESULTS: The search strategy initially identified 767 studies. The references from 1983 onwards totaled 727 articles. Fifty-four studies were identified without repetition within the selection criteria. Two articles showing significance in the development of treatment techniques were included. Additional hand-searching yielded 13 additional papers. Thus, a total of 69 studies were included. CONCLUSIONS: Prospective randomized controlled studies of MAFs repair techniques are scarce. The available data at best predict that complications are associated with all kinds of fixation techniques. The similar results of complications in studies using different methods of fixation indicate that biomechanics are only one factor to be considered when treating MAFs. A second fracture in the mandible (which was observed in the majority of the studies' population) can confound the outcome data because the fixation requirements of a double fracture are often different from those for an isolated fracture. It can be necessary additional effort intended for increase of stability when using biodegradable plate system to fixate MAFs. The use of 1.3 mm malleable miniplates was associated with an unacceptable incidence of plate fracture, suggesting that this is not the most adequate system to treat MAFs. The use of the 3D grid plates has shown good clinical results. The efficiency of locking miniplate system is yet to be proven because there are few clinical studies with its use to fixate MAFs, although they have shown good results. When considering the use of semirigid or rigid fixation systems, the use of two miniplates outweigh the advantages of the use of one reconstruction plate, although the use of miniplates is not recommended for displaced comminuted MAFs. Although it has been shown that absolute rigid fixation is not necessary for fracture healing, any system that provides superior stability without impacting negatively on other aspects of the procedure, i.e., time, exposure, and cost, should be favored. MAFs can be treated in a highly effective way and with a relatively low rate of complications with monocortical miniplate fixation. The large number of studies on the treatment of MAF reflects the fact that a consensus has not been reached for a single, ideal treatment method.Oral and Maxillofacial Surgery 11/2012;