Healing following GTR treatment of intrabony defects distal to mandibular 2nd molars using resorbable and non-resorbable barriers

Aims: The objectives of the present, randomised clinical trial were (i) to evaluate the healing of periodontal intrabony defects at the distal aspect of mandibular 2nd molars using a resorbable polylactic acid (PLA) barrier a nd a non-resorbable polytetrafluoroethylene (e-PTFE) barrier and (ii) to co mpare the therapeutic effect of the bioresorbable versus the non-resorbable barrier. Method: 19 patients with intrabony defects distal to mandibular 2nd molars greater than or equal to 4 mm (on radiographs) were included in the study. The defects all remained 5 years after surgical removal of impacted 3rd mol ars. Following flap elevation and defect debridement, the defects were rand omly covered with, either a resorbable PLA or a non-resorbable e-PTFE barri er. Flaps were repositioned and sutured to completely cover the barriers. T reatment was evaluated clinically after 1 year by measurements of probing d epth (PD), probing attachment level (PAL), and probing bone level (PBL) and radiographically by measurements of bone levels on computer digitised imag es of radiographs taken immediately before and 1 year postsurgery. Results: Both treatments resulted in significant PD reduction, PAL gain, an d bone fill. The total PD reduction was 5.3+/-1.9 mm for the PLA treated si tes and 3.7+/-1.7 rum for the e-PTFE treated sites (p<0.05). The correspond ing values for PAL gain were 4.7+/-0.7 mm and 3.6+/-1.7 mm (p<0.05) and for PBL gain 5.1+/-1.2 and 3.3+/-2.0 mm (p<0.05). Radiographic bone fill avera ged 3.4+/-1.2 for the PLA and 2.0+/-1.6 mm for the e-PTFE barriers (p<0.05) . Radiographic bone level measurements were significantly smaller than the corresponding clinical measurements, indicating that radiographs tend to un derestimate bone fill. Conclusions: GTR treatment of deep intrabony defects distal to mandibular s econd molars using resorbable PLA barriers resulted in significant PD reduc tion, PAL gain and bone fill at least equivalent to the results obtained us ing nonresorbable e-PTFE barriers.