Periodontal regeneration of intrabony defects with resorbable and non-resorbable membranes: 30-month results

The aim of this prospective split-mouth-study was to compare the healing results in intrabony defects 12 and 30 months after placement of resorbable (polyglactin-910) and non-resorbable (e-PTFE) GTR-membranes. 11 healthy patients with 30 defects participated. 10 patients with 10 pairs of contralateral lesions, which were treated with both membrane types, were included in the split-mouth-design. Furthermore, in an additional group-design all 30 (16 polyglactin-910 and 14 e-PTFE) treated sites were evaluated, Clinical examinations (PBI, REC, PPD PAL) and radiographic examinations were carried out under standardized conditions immediately before as well as 12 and 30 months after surgery. Additionally, for the assessment of the effectiveness of the 2 membranes by comparing the regeneration results of different defects, the vertical relative attachment gain (V-rAG) was calculated as a % of the PAL gain related to the maximum possible attachment gain (expressed by the baseline depth of the osseous defect intraoperatively measured). Digital subtraction radiography (DSR) was carried out for the quantitative assessment of bone density changes due to GTR. In the split-mouth-design, both types of membranes provided significant V-rAGs (median) after 12 months (polyglactin: 81.7%; e-PTFE: 100.0%) and after 30 months (polyglactin: 69.1%; e-PTFE: 83.8%) compared to baseline. In 90.0% of the polyglactin and e-PTFE sites, a probing attachment gain of at least; 2 mm was maintained over the 30-month period. However, in 2 polyglactin treated sites, and 5 e-PTFE treated sites, a new attachment loss was found between 12 and 30 months. DSR showed bone density gain 12 and 30 months postsurgically. No statistically significant differences could be observed between the 2 membrane materials with regard to clinical and radiographic findings. This was confirmed when considering the total number of defects (group-design). In conclusion, based on this 30-month-study resorbable polyglactin membranes may be regarded as a useful alternative to the well established e-PTFE membranes for the treatment of intrabony defects.