An interesting article titled “Orthodontic Extraction of High-Risk Impacted Mandibular Third Molars in Close Proximity to the Mandibular Canal: A Systematic Review,” written by Mahmood Reza Kalantar Motamedi and et al. appears in the 2015 Journal of Oral and Maxilofacial Surgery (issue 73, pp. 1672-1685). The article describes extraction of lower wisdom teeth in close proximity to the mandibular canal which is high risk and called orthodontic extraction.
The authors searched for case reports, case series, retrospective analyses, and clinical trials that reported orthodontic extraction of wisdom teeth with high risk of inferior alveolar nerve injury. The study population included patients scheduled for elective surgical removal of impacted mandibular wisdom teeth in close proximity to the mandibular canal as visualized by radiographic examination. Various databases were searched.
The selected studies consisted of publications from August 1996 to March 2014 and the number of impacted mandibular wisdom teeth ranged from 1 to 64, with a total of 143 cases of mandibular impactions. Of these, 123 underwent orthodontic extraction and only 2 patients developed temporary paresthesia. A panoramic radiograph was the primary diagnostic predictor in all the included studies. If the wisdom teeth was deemed to be in close proximity to the mandibular canal, then a CBCT or CT scan was ordered for further evaluation. Different orthodontic mechanical therapies were carried out in these studies.
Based on reviewing the studies the authors came up with a series of recommendations. After the diagnosis of an impacted wisdom teeth with high risk of nerve injury orthodontic extraction technique should be used in the follow situations:
1. For horizontally and distally impacted wisdom teeth or when it appears that a 1-stage coronectomy will not move the tooth far enough from the mandibular canal.
2. For impacted wisdom teeth associated with cysts.
3. When the postoperative osteo-periodontal status of the adjacent second molar is a concern.
4. When wide-sectioning of the wisdom teeth is needed and consequent pulp exposure and infection are probable.
Regardless of the drawbacks of orthodontic extraction, removal of deeply impacted wisdom teeth is safe with regard to mandibular nerve injury and neurologic damage.