The use of guided tissue regeneration principles in endodontic surgery for induced chronic periodontic-endodontic lesions: A clinical, radiographic, and histologic evaluation

Background: Chronic periodontic-endodontic lesions are not uncommon in clinical practice and their regenerative capacity has long been questioned. However, there are no published studies investigating the application of guided tissue regeneration techniques in combination with endodontic surgery using an induced perio-endo defect model. This study evaluated the clinical, radiographic, and histologic outcomes of three surgical procedures used to treat induced perio-endo lesions. Methods: Pulpal necrosis was induced in foxhounds along with surgical removal of radicular buccal bone. After 4 weeks, chronic lesions were clinically and radiographically assessed. Treatment surgery consisted of apicoectomy, root canal instrumentation, and retrofilling with mineral trioxide aggregate. Teeth were then assigned to one of the following treatment groups: open flap debridement only (OFD), OFD with bioabsorbable porcine-derived Collagen membrane (BG), or OFD with BG and anorganic bovine bone matrix (BO/BG). Clinical parameters and standardized radiographs were assessed at defect creation; treatment surgery; and at 1, 2, 4, and 6 months. Animals were sacrificed at 6 months and specimens prepared for histometric analysis. Results: Clinical and radiographic conditions improved during the study period. Mean epithelial attachment was similar between all groups. Mean connective tissue attachment for groups OFD, BG, and BO/BG was 3.79 mm, 2.63 mm, and 1.75 mm, respectively, and mean radicular bone height was 2.16 mm, 3.24 mm, and 3.45 mm, respectively. Statistically significant increases in the amount of new cementurn were observed in groups BG and BO/BG when compared with OFD (P < 0.05). Conclusions: Treatment of combined induced perio-endo lesions using bioabsorbable Collagen membranes alone or in combination with anorganic bovine bone matrix resulted in increased amounts of bone, periodontal ligament, and significant increases in the amount of new cementurn when compared to open flap debridement in a canine model.