Third Molar Site Grafting
I recently attended a symposium on alveolar grafting and ridge preservation. One of the speakers, Thomas B. Dodson, DMD, presented an interesting paper dealing with the effects of mandibular third molar (M3) removal on the periodontal health of the adjacent second molar (M2). He also addressed weather additional surgical procedures at the time of removal such as guided tissue regeneration (GTR), grafting with bone substitute, or platelet-rich plasma (PRP), improved the outcome to M2. He reviewed about 20 quality articles on this subject.
In brief, his findings help answer the following clinical questions:
- Does the extraction of 3rd molars adversely affect the periodontal health of the 2nd molar? The bulk of evidence suggests that the periodontal status of M2 remains unchanged or improves following M3 extraction. Ninety percent of the time the periodontal attachment was unchanged or improved following M3 removal. In no case was there an increase in probing depth of greater then 2mm.
- Do additional surgical procedures at the time of M3 extraction improve the periodontal outcome of M2? Routine application of additional surgical procedures did not improve the periodontal parameters on the distal of M2 except in High Risk Patients where there was significant improvement over the control groups. The amount of pocket reduction varied from 2mm to 3mm in the control group to 4mm to 6mm in the treated group (bone grafting or PRP).
The high risk patients were identified as:
- Unusual large bony defect such as seen when there is an associated cyst involved with the M3.
- Patients over the age of 25 with a mesial or horizontal impaction and existing periodontal probing depth of greater than 4mm.
In summary, his presentation concluded that removal of M3 will improve the periodontal integrity of M2 in most cases. And, additional surgical procedures, such as bone grafting or PRP can significantly improve the periodontal health of M2 in specific individuals that are at risk for periodontal defects.