Assessment of the trapezoidal miniplate with posterior extension for open management of condylar fractures: Can it be used instead of straight miniplates?

Abstract Objective This study comparatively measures and evaluates the strength of five plating techniques for mandibular condylar fracture fixation when linear loading is applied. Materials and Methods The investigators designed and implemented a cross‐sectional in vitro study. The sample was composed of 60 polyurethane mandibles for the mechanical tests. For the photoelastic test, 10 photoelastic mandibles were used. The predictor variable is the plating technique, and it was categorized as groups G2P‐2.0: two 4‐hole 2.0 mm straight plates, G1TP‐2.0: 4‐hole 2.0 mm trapezoidal plate; G1TPPE‐2.0: 4‐hole 2.0 mm trapezoidal plate with posterior extension; G1TP‐1.5: 4‐hole 1.5 mm trapezoidal plate and G1TPPE‐1.5: 4‐hole 1.5 mm trapezoidal plate with posterior extension. The outcome variable is the strength of the plating techniques that was evaluated with the loading test: peak/ending load and peak/ending displacement measures collected. The photoelastic test was used to detect tension distribution throughout the structure helping to understand the material's behaviour. Values of the loading test were analysed using SAS (SAS Institute, Cary, NC, EUA). A p <0.5 ( p = 0.05) was considered significant and means were compared using the Tukey test. Results The results indicated that the fixation with two plates presented a higher resistance in the anteroposterior direction and fixation with a trapezoidal plate with posterior extension is more resistant towards mediolateral. The photoelastic analysis showed that the strain lines were best distributed when trapezoidal plates were used. Conclusion According to the results, the posterior extension of the trapezoidal plates increased the strength of the fixation system, and the use of trapezoidal plates with or without posterior extension was favourable to a more balanced stress distribution. However, clinical studies must be done to confirm the biomechanical findings.