ABSTRACT
At present, there is considerable evidence to support ultrasonic scaling as one of the most effective procedures for treatment of periodontal disease.However, sometimes, root anatomy precludes achievement of the desird results.The aim of this study is evaluation of clinical and microbiological effects of Nd:Y.A.G laser accompanied with scaling and root planning .Six patients with chronic periodonthiths, each of whom had two or more sites with probing depth measuring five or six mm in each quadrant were included in this clinical trial.52 sites were randomly assigned treatment with either conventional therapy [n=26] or Nd:Y.A.G accompanied by conventional therapy [n=26][2w-20pps-120seconds pulse duration 100ms]. At base line, one day, one month and two months after procedure, clinical measurments [probing depth, Gingival index, Bleeding index] were preformed and microbial flora[porphyromonas gingivalis] sampled using a cultural technique.Pockets depths after one month [P=0.004],bleeding index after one month [P=0.002] and after two months [P=0.006] were positively influenced by adjunctive laser therapy in comparision to conventional therapy. Gingival index after two months [P=0.0032]was positively influenced by laser therapy but there was no difference after one month [P=0.439].[P=0.852]. After one month, the average of p.g[P=0.064] in the test sites was less that control sites.The effectiveness of Nd:Y.A.G laser as an adjuvant in treatment of periodontitis was demonstrated .In term of bacteriocidal efficacy, the application of Nd :Y.A.G laser proves to be a complementary therapuetic measure but more studies are needed