The effect of regenerative periodontal therapy in preventing periodontal defects after the extraction of third molars: A systematic review and meta-analysis.

BACKGROUND: Periodontal defect on the distal aspect of mandibular second molars is a common complication after mandibular third-molar extraction. Researchers have proposed different procedures, but no evidence has shown that a single effective method can prevent or treat this complication.
METHODS: The authors conducted a systematic review and meta-analysis to answer this clinical question: what is the effect of regenerative periodontal therapy on the periodontal tissue healing of the distal site of the mandibular second molar after impacted mandibular third-molar extraction compared with extraction alone without using any biomaterials during a follow-up period of at least 6 months? The authors conducted an electronic search for randomized controlled trials using MEDLINE, Embase, and other databases, and they assessed the quality of selected articles.
RESULTS: Among the 1,083 eligible articles found in the initial search, 7 studies fit all of the selection criteria. All of these studies had a follow-up period lasting at least 6 months. The authors found that regenerative periodontal therapy was significantly more effective in gaining clinical attachment level or reducing probing depth at the distal site of the mandibular second molar than extraction without therapy (weighted mean difference of clinical attachment level gain, 1.94 millimeters [95% confidence interval {CI}, 1.56-2.31]; weighted mean difference of probing depth reduction, 1.67 mm [95% CI, 1.15-2.19]). CONCLUSIONS AND PRACTICAL IMPLICATIONS: The results of our systematic review and meta-analysis demonstrated that regenerative periodontal therapy effectively prevents the periodontal defect associated with impacted mandibular third-molar extraction. Clinicians should consider performing guided tissue regeneration when the defect is anticipated.