The Effect of Timing of Orthodontic Therapy on the Outcomes of Regenerative Periodontal Surgery in Patients with Stage IV Periodontitis: A Multicenter Randomized Trial.

Aim To compare the outcomes after early (4 weeks post surgery) or late (6 months post surgery) orthodontic therapy (OT) following regenerative surgery of intra-bony defects (IDs). Materials and methods In a multi-center, parallel-group, randomized clinical trial, 43 patients with stage IV periodontitis were randomized to receive either early (n = 23) or late OT (n = 20) following regenerative surgery of IDs. Primary outcome was change in clinical attachment level (CAL) in one target ID at 12 months after surgery. Secondary outcomes were changes of probing pocket depth (PPD), bleeding on probing (BOP), and frequency of pocket closure. Results No statistically significant differences between groups could be observed for CAL gain (5.4 mm [+/- 2.1 mm] for early; 4.5 mm [+/- 1.7 mm] for late OT). PPD was reduced by 4.2 mm (+/- 1.9 mm) in the early group and by 3.9 mm (+/- 1.5 mm) in the late group (p > .05). Pocket closure (PPD <= 4 mm) was obtained in 91% of defects in early compared to 85% in late OT. Conclusion In the inter-disciplinary treatment of periodontitis stage IV, OT can be initiated already 4 weeks after regenerative surgery of IDs with favourable results, thus reducing the overall treatment time.