Evaluation of Efficacy of Herbert Bone Screw and Lag Screw in Management of Oblique Mandibular Fractures: A Prospective Randomized Comparative Study

Purpose: To assess the efficacy of Herbert cannulated bone screw versus Lag screw in fixation of oblique mandibular fractures.

Materials and method: Study composed of two groups of 20 patients each and descriptive statistics were performed with p value set at 0.05 with confidence interval of 95%. Group A was treated by Titanium Lag screws; while, Group B was treated by Titanium Herbert Cannulated Bone Screws for the management of oblique mandibular fractures. Postoperatively, all the patients were evaluated clinically and radiographically by recording the incidence of complications (if any) which included trismus, neurosensory deficit, swelling, infection. Parameters such as occlusal discrepancy, rigid fixation (interfragmentary gap) and duration of surgery were also recorded for all the patients.

Results: All the patients were followed for a period of three months. Difference in mouth opening was found to be statistically significant during 1st month follow-up (p-Value-0.002). Postoperatively, the mean interfragmentary gap in Group A was significantly more than Group B (p-Value-0.000). Other parameters like neurosensory deficits, occlusal discrepancies, chewing efficiency, stability of fractured fragments and post-operative complications in terms of swelling, hardware exposure, radiolucency surrounding screw and wound dehiscence did not show any statistically significant difference.

Conclusion: The obtained results showed that both lag screws and Herbert cannulated bone screws fulfill the treatment goals of adequate reduction, fixation and stabilization of oblique mandibular fractures. Herbert screws have shown to have better results in terms of interfragmentary gap reduction as compared to lag screws.