Risk assessment of inferior alveolar neurovascular bundle by multidetector computed tomography in extractions of third molars.

PURPOSE: This study aimed to assess the reliability of multidetector computed tomography (MDCT) in determining the surgical risk of the inferior alveolar neurovascular bundle in extractions of third molars.

METHODS

The sample comprised thirty-three individuals (63 third molars) who underwent preoperative evaluation by MDCT before extraction of impacted mandibular third molars. MDCT was used to determine the relationship between the roots of the third molars and the mandibular canal, and the course of the mandibular canal. Inferior alveolar nerve (IAN) exposure and the presence of hemorrhage were analyzed after removal of the teeth. IAN neurosensory deficit was recorded after 7 days. Clinical and MDCT findings were compared using Fisher's exact test (P < 0.05).

RESULTS

There was a statistically significant association between IAN exposure and the tomographic relationship between the roots of third molars and the mandibular canal (P = 0.015). Conventionally, all cases of IAN neurosensory deficit and hemorrhage occurred when the roots of the third molar presented in an at-risk relationship with the mandibular canal, however, this association was not statistically significant (P > 0.05). A statistically significant association was found between the lingual course of the mandibular canal and IAN exposure (P = 0.03).

CONCLUSIONS

MDCT is an effective tool for determination of the surgical risk to the inferior alveolar neurovascular bundle in extraction of mandibular third molars.