Patterns of Root Morphology of Mandibular Third Molars and Their Clinical Implications in a Cohort of Sri Lankan Patients

Background: Mandibular third molar surgeries garnered recognition as one of the common treatment procedures provided by Oral & Maxillofacial practices across the globe. Mandibular third molars are not only impacted, often giving rise to bothering issues to patients ranging from pain to difficulty in opening mouth but create challenges in their surgical removal. Postoperative complications of those surgeries such as pain, swelling, trismus and alveolar osteitis (dry socket) could be prevented and controlled by meticulous preoperative assessment of tooth-related and patient-related factors. Pattern of root morphology could be one important tooth- related factor connected to difficulties and subsequent postoperative complications of mandibular third molar surgeries. Aim: Against this backdrop, the aim of this study was to explore the patterns of root morphology of mandibular third molars and to elucidate their associations with selected attributes of the surgeries, self-reported preoperative pain and selected postoperative complications among a cohort of Sri Lankan patients. Materials & Methods: A hospital based, descriptive cross-sectional study was conducted among 715 patients (represented wider age range from adolescents to older adults) who underwent surgical removal of mandibular third molars at the Department of Oral & Maxillofacial Surgery, Faculty of Dental Sciences, University of Peradeniya, Sri Lanka. Of extensive socio-demographic, clinical and radiological investigation data collected, those data on root morphology and numbers of roots, inferior dental canal relationship, self-reported preoperative pain, duration of the surgery, flap design, tooth sectioning and postoperative pain and swelling complications were used for the present analysis. Data entry and analysis was done using SPSS-21 Statistical Software Package. Results: Based on our findings on patterns of root morphology, straight two roots were the most common (34.4%) across all age groups, followed by convergent two- roots (19.3%) fused straight- roots (16.3%) and distally curved two- roots (13.8) among Sri Lankan patients. Almost half (46.8%), of patients had inferior dental nerve canal placed away from mandibular third molar roots. Moreover, root morphology was significantly associated with presence of preoperative pain, duration of the surgery as well as occurrence of postoperative swelling (p<0.05). Conclusions: Patterns of root morphology of mandibular third molars may implicate on certain processes of their surgical removal and its outcomes. Therefore, careful preoperative assessment of root morphology and related factors of those teeth becomes useful in tailored patient care for minimal postoperative complications, better patient experience and quality-of-life.