Aim: A randomized-controlled clinical pilot trial was designed to evaluate photodynamic therapy (PDT) for its bactericidal potential and clinical effect in the treatment of periodontitis.
Material and methods: Fifty-eight subjects with chronic periodontitis were included. Each subject exhibited at least three active periodontal pockets 5mm or deeper, bleeding on probing and the presence of Porphyromonas gingivalis. Subjects were randomly assigned to a control group treated by subgingival ultrasound only or to a study group additionally treated by PDT. Baseline clinical values of gingival index, bleeding on probing, probing pocket depths and clinical attachment levels were recorded and re-evaluated 90 days later. Pathogen screening for P. gingivalis, Tannerella forsythia and Treponema denticola was conducted at baseline as well as 10, 42 and 90 days after treatment.
Results: P. gingivalis was significantly reduced in both groups (laser group: p=0.020; control group: p=0.042). No significant reductions of T. forsythia and T. denticola were observed in either group. For the microbial parameters, no significant difference was found between the laser and the control group. All clinical parameters were significantly reduced in both groups after treatment. The mean probing pocket depths decreased from 5.79 to 4.55mm in the laser group and from 5.54 to 4.51 in the control group. The intergroup difference was not significant (p=0.82). Bleeding on probing was reduced from 100% evaluated at baseline to 47% in the laser group and 59% in the control group. The intergroup difference was not significant (p=0.28). No significant differences were observed in any other parameters.
Conclusion: Application of a single cycle of PDT was not effective as an adjunct to ultrasonic periodontal treatment. There were no extra reductions in pocket depths and bleeding on probing. With regard to eradicating bacteria, however, there are no additional effects as compared with conventional treatment alone.