THE GUIDED TISSUE REGENERATION PRINCIPLE IN ENDODONTIC SURGERY - ONE-YEAR POSTOPERATIVE RESULTS OF LARGE PERIAPICAL LESIONS

Twenty patients with large endodontic lesions, which failed to respond to conventional endodontic therapy, were selected for this study. The lesions had a radiographic diameter of at least 10 mm, were removed b y periradicular surgery, before retrofilling the apices with either su per EBA or dessicated zinc oxide-eugenol. In 10 test sites large e-PTF E membranes (Gortex) were placed to cover the lesions, while at the co ntrol sites the lesions were not covered before resuturing. Radiograph ic analysis of the lesions at 3, 6, 9 and 12 months revealed that lesi ons covered with the membranes healed quicker than the control lesions , and that the quality and quantity of the regenerated bone was superi or when membranes were used. Results of the study indicate that guided tissue regeneration (GTR) principles can be effectively applied to th e healing of large periapical lesions, especially in through-and-throu gh lesions.