OPG vs CBCT in Evaluating Difficulty Index of Impacted Mandibular Third Molar Extraction in South Indian Population

Aim: This study aimed to compare cone beam computed tomography (CBCT) and orthopantomogram (OPG) in assessing mandibular third molar impactions and their relationship with the inferior alveolar nerve (IAN) canal in South Indian population. Methods: The study compared OPG & CBCT images from 254 individuals aged 18-45 years with unilateral or bilateral mandibular third molar impaction, was evaluated for the effectiveness in identifying key parameters, including mandibular height, second molar angulation, and canal placement. Result: CBCT demonstrated higher accuracy than OPG, particularly for assessing mandibular canal position and cases in specific angulation ranges (70-79 degrees). CBCT also identified more cases of distal cusp coverage and available space for impacted teeth compared to OPG. While root morphology and follicular diameters showed no significant differences between imaging methods, a statistically significant association was found between mandibular height and canal location (p-value <0.05). CBCT achieved a mean score of 4.58, reflecting its enhanced precision in complex cases such as impacted third molars. The findings emphasize CBCT’s superiority in providing detailed anatomical information essential for surgical planning, reducing the risk of iatrogenic damage to critical structures like the IAN during mandibular third molar extractions. Conclusion: The study concludes that CBCT is a more effective diagnostic tool than OPG for preoperative assessment, particularly in cases where precise anatomical relationship visualization is necessary, and recommends further research to improve preoperative assessments and reduce extraction complications.