010: Avoid Nerve Injury In Lower Third Molars

In this episode, I want to discuss a very specific but important topic—how I use panorex X-rays to evaluate lower third molars and decide on the best treatment approach, whether that's deferral, coronectomy, or extraction.

While CBCTs provide 3D imaging, I still find panorex to be a valuable screening tool that I use all the time in my oral surgery practice.

When looking at a panorex in relation to lower third molars and the inferior alveolar nerve canal, there are several key things I assess to determine nerve injury risk:

1. Is the superior cortical border of the canal intact or disrupted where it crosses the tooth roots?

2. Are the third molar roots deflected?

3. Does the canal divert or change direction as it approaches the tooth?

4. Is there narrowing of the canal near the tooth roots?

5. Is there darkening of the tooth roots, indicating canal involvement?

6. Do the roots appear narrowed near the canal?

7. In rare cases, is there bifurcation or perforation of the roots by the canal?

Disruption of the cortical border, root darkening, and canal diversion are the findings I see most often that point to high nerve injury risk. When I note these signs, I'm likely to recommend either CBCT for further evaluation or coronectomy/deferral rather than proceeding with extraction.

I explain these panorex risk factors not just for my oral surgery colleagues, but to help referring dentists understand what I look for and why I may recommend a certain approach after they send a patient my way.

I'm always eager to discuss these topics further, so please leave a comment if you have any other thoughts or questions. Thanks for tuning in!