The Use of Coronectomy to Manage Symptomatic Mandibular Third Molars: Techniques, Pitfalls and Suggested Guidelines

Coronectomy remains a hotly debated issue in the management of the symptomatic mandibular third molar. Use of the technique varies greatly between practitioners, and often fails to adopt an evidence-based approach. While many operators still do not recognize the technique as a valid method of managing a symptomatic third molar, others have inappropriately adopted use of the technique in all cases judged as ‘high risk’. It is widely accepted that the principal factor influencing a decision to undertake coronectomy should be an increased risk of inferior alveolar nerve (IAN) injury, although the exact risk threshold for coronectomy to be warranted remains poorly defined and open to interpretation. Some evidence through randomized controlled trials undermines the routine use of the technique, as the significance of reduced permanent nerve injury when compared to full surgical removal appears questionable.^1,2 Indeed, primary endpoints for trials have analysed temporary rather than permanent nerve injury owing to the large patient numbers required to demonstrate differences in permanent injury rates between coronectomy and full surgical removal. This may indicate that, although a statistically significant difference could exist, it is not clinically important to the general ‘high-risk’ population. Compounding this finding is the fact that a small number of coronectomied roots will become symptomatic over time, exposing the patient to the further risk of repeat treatment in a surgical field that lacks the usual anatomical landmarks afforded by the presence of a crown.