Single-flap Approach in Guided Tissue Regeneration for Periodontal Intraosseous Defects

Objectives: A single-flap approach (SFA) is an elevation of only one-side periodontal flap to access intraosseous defects. The purpose of this study was to evaluate clinical and radiographic outcomes of SFA for guided tissue regeneration (GTR) with a collagen membrane and bone graft.
Methods: This retrospective study was conducted under the approved IRB protocol (HP-00078777). Nine patients who received GTR therapy using a collagen membrane and demineralized freeze-dry bone allograft via SFA by SO from 2012 to 2017 were reviewed. The data for gingival recessions (GRs) at the flap sides and pocket depths (PDs) and crestal bone loss (CBL) at the defect sites were retrieved. A blind evaluator (SJ) measured crestal bone levels on radiographs from the cementoenamel junction to the deepest point in intraosseous defects. Differences in outcome variables between presurgery and postsurgery were evaluated using a paired t-test for GRs and Wilcoxon signed-rank test for PD and CBL.
Results: Eleven cases in 5 males and 4 females with the mean age of 58±18 year-old were included. One patient was diabetic with HbA1c 6.5%. Pearson’s r was 0.94, demonstrating a high degree of agreement between SO and SJ in measurement of crestal bone loss (CBL) on radiographs. There were a significant reduction in mean PD from 7.6±2 mm presurgery to 4.1±1 mm postsurgery (p=0.006) and a significant bone regeneration from 8.6±4 mm presurgery mean CBL to 6.7±3 mm postsurgery mean CBL (p=0.011) at the defect sites during 16±4 months follow-up. Although a significant gingival recession (GR) at the mesial site in the flap side was observed, the mean amount of GR (0.55mm) was clinically insignificant.
Conclusions: A SFA for GTR with bone graft is effective to regenerate alveolar bone in intraosseous defects. This approach is also minimally-invasive, resulting in significant decreased PD and minimum GR in the flap side during 16±4 months.