title: A preliminary study on the effects of the Nd:YAG laser on root surfaces and subgingival microflora in vivo.
abstract: The purpose of this study was to examine the effects of root preparation using the pulsed Nd:YAG laser, either alone or in combination with manual instrumentation. Study specimens consisting of 18 teeth with associated periodontal pockets from 8 different patients were treated as follows: 5 specimens were root planed with curets followed by laser exposure for 3 minutes using energy settings of 3.0 W at 20 pps; 2 specimens were root planed and then laser treated for 3 minutes using settings of 2.25 W and 20 pps; 4 specimens were treated by laser for 1 minute at settings of 1.75 W and 20 pps followed by root planing; 4 specimens were treated by laser only for 1 minute using settings of 1.75 W and 20 pps; and the remaining 3 teeth served as untreated controls. Both prior to and after completion of the laser and root planing treatments, microbiological samples were obtained from the treated pockets and submitted to a commercial laboratory for analysis of levels of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Prevotella intermedia. With the exception of two 7-day specimens, all others were extracted immediately post-therapy and processed for SEM examination. All treated specimens, regardless of treatment sequence, exhibited some degree of laser-induced root surface alteration. Notably, laser-treated calculus deposits were free of their characteristic surface layer of microbial plaque. Microbial sampling indicated a post-therapy reduction in levels of all 3 putative microbial pathogens compared to pre-treatment samples and control specimens. However, SEM examination revealed residual deposits of plaque and calculus in all treatment groups.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Periodontics, School of Dentistry, University of Missouri-Kansas City.
authors.forename: C M
authors.initials: CM
authors.lastname: Cobb
authors.forename: T K
authors.initials: TK
authors.lastname: McCawley
authors.forename: W J
authors.initials: WJ
authors.lastname: Killoy
mesh_terms: D000328:Adult; D000368:Aged; D016976:Aggregatibacter actinomycetemcomitans / Q000302:isolation & purification / Q000648:ultrastructure; D000538:Aluminum Silicates; D001419:Bacteria / Q000302:isolation & purification* / Q000648:ultrastructure; D001439:Bacteroides / Q000302:isolation & purification / Q000648:ultrastructure; D005260:Female; D005881:Gingiva / Q000382:microbiology*; D006801:Humans; D053685:Laser Therapy; D008028:Light Coagulation; D008297:Male; D008855:Microscopy, Electron, Scanning; D008875:Middle Aged; D009354:Neodymium; D010514:Periodontal Pocket / Q000382:microbiology / Q000628:therapy; D010518:Periodontitis / Q000382:microbiology / Q000628:therapy; D016966:Porphyromonas gingivalis / Q000302:isolation & purification / Q000648:ultrastructure; D016745:Root Planing / Q000379:methods; D014092:Tooth Root / Q000601:surgery* / Q000648:ultrastructure; D015019:Yttrium
chemical_list: D000538:Aluminum Silicates; D009354:Neodymium; D015019:Yttrium