[Implementation of transgingival antibacterial photodynamic therapy (PDT) supplementary to scaling and root planing. A controlled clinical proof-of-principle study].

Background: The antibacterial photodynamic therapy (PDT) has been effective in the periodontal therapy. The laser light application reported in the literature so far is the subgingival placement of a light fibre.

Objectives: To study the effect of PDT with a transgingival laser application.

Materials and methods: In 19 patients with untreated periodontitis 1 test and 1 control site were selected. Both pockets were treated by scaling, root planing. the Test site received additional PDT (LASOTRONIC MED 701 by ORCOS MEDICAL, Switzerland) at baseline, after 2 and 6 months. The control sites were rinsed with ringer solution. Clinical parameters (ST, BOP, CAL) and bacterial monitoring (PADO, IAI, Switzerland) at baseline, 2 and 6 months were recorded.

Results: Mean pocket reduction was after 6 months 2.1 mm (+/-1.4) in the test group, 1.5 mm (+/-1.6) in the control group significantly different. The 95% confidence interval for the difference of the mean reductions of the test and control group after 6 months is (1.5, 3). Mean CAL gain after 6 months was 1.5 mm (+/-1.3) in the test, 0.9 mm (+/-1.7) in the control group. T. denticola showed lower number after 2 and 6 months in the test versus the control. The total bacterial load (TBL) showed significantly better reduction in the test group at 6 months.

Conclusions: The transgingival application of PDT with the MED 701 showed clinical and bacteriological effects which are comparable to those reported in the literature with the subgingival method. The transgingival method is convenient, harmless and easy to perform.