Coronectomy: a surgical option for impacted third molars in close proximity to the inferior alveolar nerve

Damage to the inferior alveolar nerve (IAN) during the extraction of impacted mandibular third molars in close proximity to the mandibular canal is a postoperative complication that most frequently occurs in patients 40 years and older.

The authors evaluated the postoperative complications of 43 coronectomies of impacted mandibular third molars in 37 patients (17 men and 20 women, mean age [standard deviation] 31 [2] years). The authors used cone-beam computed tomographic images to determine that all of the teeth that underwent a coronectomy were in close proximity to the IAN.

The authors did not observe neurological injuries to the IAN or to the lingual nerve. One patient complained of intermittent pain and, 10 months after undergoing the coronectomy, underwent a second operation for extraction of the root fragments. The root extraction did not result in any neurological deficits, because the root fragments had migrated from the mandibular canal. One case of alveolitis was reported that manifested 15 days after the coronectomy.

Coronectomies are safer to perform than complete extractions in situations in which the third molar is in close proximity to the mandibular canal. Root migration generally is asymptomatic, but in a case in which the patient underwent a second operation, the risk of the patient's experiencing neurological injuries was reduced.

Coronectomy appears to be a valid surgical alternative in patients 40 years and older who are at a higher risk of experiencing neurological deficits than are younger patients.