Association of Radiographic Signs in Determining the Proximity of Mandibular Third Molar Roots to the Mandibular Canal and Postoperative Occurrence of Neurosensory Disorders: A Cohort Study

BACKGROUND: The routine oral and maxillofacial procedure involving the surgical removal of impacted mandibular third molars comes with inherent risks to nearby anatomical structures. Proximity of mandibular third molar roots to the inferior alveolar nerve (IAN) poses a significant risk for injury, prompting the need for reliable assessment methods. Radiographic indicators, particularly those observed on intraoral periapical radiographs (IOPARs), offer a dependable means to evaluate proximity.

OBJECTIVES: This study seeks to examine the closeness between the mandibular canal and the roots of mandibular third molars using IOPARs and to assess the incidence of postoperative neurosensory disorders.

METHODS: A cohort of 100 subjects aged 18 to 25, presenting for partially erupted/ impacted mandibular third molar removal, underwent IOPAR examinations. Data analysis employed IBM SPSS Statistics for Windows, Version 12 (Released 2004; IBM Corp., Armonk, New York, United States), calculating frequencies, percentages, means, standard deviations, and ranges. Radiographic signs of proximity were evaluated, and a standardized surgical procedure was performed under local anesthesia. Postoperative neurosensory disorders were assessed using various methods.

RESULTS: Of the evaluated subjects, darkening of the root (52%) was the most prevalent radiographic sign, followed by interruption of the white line of the canal (20%). The prevalence of radiographic signs varied, with none of the patients experiencing narrowing of the root. Postsurgical paraesthesia assessment revealed no nerve sensitivity alterations in any patient.

CONCLUSION: Preoperative radiographic examination is imperative for determining the relationship between mandibular third molar roots and the inferior alveolar canal, aiding in preventing IAN damage during extraction. Contrary to radiographic signs, there was no observed association between impacted mandibular third molar radiographic signs and the occurrence of postoperative neurosensory disorders.