Management of Teeth in the Line of Mandibular Angle Fractures Treated with Open Reduction and Internal Fixation: A Systematic Review and Meta-Analysis

Background: Mandibular angle fractures are common and frequently involve a tooth in the fracture line. Despite trends toward more conservative indications for tooth extraction during open repair, the literature remains heterogeneous. This review aims to ascertain the effect of tooth extraction/retention on patient outcomes following mandible open reduction and internal fixation and to evaluate the evidence surrounding indications for extraction. Methods: PubMed, EMBASE, the Cochrane Library, Elsevier text mining tool database, and were queried through March of 2018 for English language publication on adults with traumatic mandibular fractures. The review protocol was not registered online. Quality of evidence was assigned using the Grading of Recommendations Assessment, Development and Evaluation methodology. Meta-analyses were performed when definitions of outcomes were deemed similar. Results: Overall, 26 of 1212 identified studies met inclusion criteria. Indications for tooth extraction and rates of extraction varied considerably across studies. The quality of evidence was low or very low for all outcomes. Tooth retention was associated with lower overall complications (OR, 0.54; 95 percent CI, 0.37 to 0.79), major complications requiring readmission or reoperation (OR, 0.47; 95 percent CI, 0.24 to 0.92), and malocclusion (OR, 0.56; 95 percent CI, 0.32 to 0.97); there was no difference in wound issues or nonunion. Removal of asymptomatic teeth was associated with inferior alveolar nerve injury (39.4 percent versus 16.1 percent). Conclusions: The literature is limited by retrospective study deign and poor follow-up; however, when indicated, tooth extraction is not associated with an increased risk of infection or nonunion. Removal of asymptomatic teeth was associated with a risk of inferior alveolar nerve injury. Additional high-quality studies are needed to evaluate potentially expanded indications for tooth extraction.