Accuracy of multiplanar reconstruction and parasagittal images in evaluating the relationship between impacted mandibular third molars and the inferior alveolar canal: a retrospective cohort study.

OBJECTIVE

To evaluate the diagnostic accuracy of multiplanar reconstruction (MPR) and parasagittal images obtained from cone-beam computed tomography (CBCT) in determining the relationship between impacted mandibular third molars and the inferior alveolar canal (IAC).

STUDY

DESIGN

This retrospective cohort study included 67 impacted mandibular third molars from 38 patients. All cases were analyzed using standardized CBCT protocols, and both MPR and parasagittal views were independently evaluated by calibrated observers. Statistical analyses assessed differences in canal position classification and inter-observer agreement.

RESULTS

MPR images demonstrated greater sensitivity in detecting direct contact and penetration of the IAC compared to parasagittal images. Statistically significant differences were observed between the 2 modalities in identifying the canal's spatial relationship to the third molar roots. Inter-observer agreement was excellent, with both Cronbach's alpha and the intraclass correlation coefficient (ICC) exceeding 0.99.

CONCLUSIONS

MPR provided a more reliable method than parasagittal imaging for preoperative assessment of the proximity between mandibular third molars and the IAC. These findings support its use to help minimize the risk of inferior alveolar nerve injury during surgical extraction.