Objectives: The purpose of the present controlled clinical trial was to compare the treatment of advanced periodontal disease with a combination of an Er:YAG laser (KEY II, KaVo, Germany) and scaling and root planing with hand instruments (SRP) to laser alone.
Material and methods: Twenty healthy patients with moderate to advanced periodontal destruction were randomly treated in a split-mouth design with a combination of an Er:YAG laser and SRP (test) or with laser (control) alone. The used energy setting for laser treatment was 160 mJ/pulse at a repetition rate of 10 Hz. Prior to treatment and 3, 6 and 12 months later the following parameters were evaluated by a blinded examiner: Plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), gingival recession (GR) and clinical attachment level (CAL). Subgingival plaque samples were taken at each appointment and analysed using darkfield microscopy for the presence of cocci,-non-motile rods, motile rods and spirochetes. No statistical significant differences in any of the investigated parameters between both groups were observed at baseline.
Results: Initially, the plaque index was 1.0 +/- 0.6 in both groups. At the 3-month examination the plaque scores were markedly reduced and remained low throughout the study. A significant reduction of the GI and BOP occurred in both groups after 3, 6 and 12 months (P < 0.05, P < 0.05, respectively). The mean PD decreased in the test group from 5.2 +/- 0.8 mm at baseline to 3.2 +/- 0.8 mm after 12 months (P < 0.05) and in the control group from 5.0 +/- 0.7 mm at baseline to 3.3 +/- 0.7 mm after 12 months (P < 0.05). The mean CAL decreased in the test group from 6.9 +/- 1.0 mm at baseline to 5.3 +/- 1.0 mm after 12 months (P < 0.05) and in the control group from 6.6 +/- 1.1 mm at baseline to 5.0 +/- 0.7 after 12 months (P < 0.05). Both groups showed a significant increase of cocci and-non-motile rods and a decrease in the amount of motile rods and spirochetes.
Conclusion: In conclusion, the present results have indicated that: (i) non-surgical periodontal therapy with both an Er:YAG laser + SRP and an Er:YAG laser alone may lead to significant improvements in all clinical parameters investigated, and (ii) the combined treatment Er:YAG laser + SRP did not seem to additionally improve the outcome of the therapy compared to Er:YAG laser alone.