[Clinical and microbiologic follow-up evaluations after non-surgical periodontal treatment with Nd: YAG laser and scaling and root planning].

OBJECTIVE Our research aimed to detect the efficacy of non-surgical periodontal treatment with Nd: YAG laser and scaling and root planning (SRP) for chronic periodontitis. METHODS We recruited chronic periodontitis patients who have more than four teeth with clinical pocket depth of 4-8 mm. These teeth were distributed in four different zones within the oral cavity. Moreover, the teeth were single root teeth and not adjacent to each other. The subordinated teeth were randomized into four groups, as follows: no treatment (C group), simple SRP (SRP group), Nd: YAG laser after SRP treatment (SRP+L group), and SRP after Nd: YAG laser treatment (L+SRP group). The four experimental observation points were as follows: before treatment (baseline) and 1 week, 1 month, and 3 months after treatment. We measured clinical indicators and collected subgingival deposits in the four time points to analyze changes of red complex in periodontitis. RESULTS The clinical indicators were better in all treatment groups than in the control group. Comparison among treatment groups indicated that the value of bleeding on probing, periodontal probing depth, and clinical attachment loss showed no difference. However, the value of plaque index in SRP+L and L+SRP presented a significant reduction at 3 months after treatment. The percentages of Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola in all treatment groups decreased after clinical treatment, and differences were observed among the treatment groups at different time points. CONCLUSIONS Non-surgical periodontal treatment with SRP and Nd: YAG laser is not more effective than SRP monotherapy. The sequence of laser treatment and SRP has no significant effect on the treatment. However, SRP with Nd: YAG laser was beneficial for plaque control. Non-surgical periodontal treatment with Nd: YAG laser may be used as an alternative to reduce and control the proliferation of microorganisms in persistent periodontitis, but it still needs further verification.