Clinical, microbiological and cytomorphometric evaluation of low-level laser therapy as an adjunct to periodontal therapy in patients with chronic periodontitis

A clinical prospective study was designed to evaluate microbiological, cytomorphometric and clinical efficacy of low-level laser therapy (LLLT) as an adjunct to periodontal therapy in the treatment of chronic periodontitis.Sixty subjects were included and randomly assigned into 2 groups: SRP (scaling root planning) group (n = 30) and LLLT + SRP group (n = 30). Clinical parameters were measured before intervention, after the fifth treatment, and after a month. All subjects received oral hygiene instructions and full-mouth conservative periodontal treatment (removal of dental plaque followed by SRP). Afterwards, in group II, Kavo LLLT (980 nm, 0.2 W, 6 J/cm2 ) was applied. Subgingival samples were collected at baseline and after the fifth treatment to quantify Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Porphyromonas gingivalis, Tannerella forsythensis and Treponema denticola by polymerase chain reaction (PCR). Gingival swabs were taken, and direct smears were prepared on slides for cytomorphometric analysis.Evaluation using clinical parameters showed better results in LLLT group. A statistically significant decrease in the prevalence of bacteria after treatment in LLLT group was observed for the following: T. forsythensis and T. denticola (P < .001), P. gingivalis (P < .01), A. actinomycetemcomitans and P. intermedia (P < .05). The values of nuclear area, perimeter and Ferret's diameter were significantly lower in both studied groups after treatment, but statistical significance was higher in LLLT group (P < .001) than in the SRP therapy group (P < .05).Low-level laser therapy as an adjunct to periodontal therapy demonstrates short-term additional bacteriological, cytological and clinical benefits.