title: Chlorhexidine's effect on sealing ability of composite restorations following Er:YAG laser cavity preparation.
abstract: OBJECTIVE
  The aim of this study was to evaluate the influence of chlorhexidine on microleakage of composite restorations in class V cavities prepared with a carbide bur (CB) and a erbium:yttrium-aluminum-garnet (Er:YAG) laser.
  
  
  METHODS
  Cavity preparations were created on the buccal surfaces of 48 bovine incisors using different methods then equally dividing them into four groups. Groups I and II were prepared with a #56 CB in a high speed handpiece while Groups III and IV were prepared with a Er:YAG laser at 350m J/4Hz on enamel and at 80.24 J/cm2 on dentin. The cavity preparations were rinsed with 2% chlorhexidine solution before the application of Clearfill SE Bond system and placement of a Z100 composite resin restoration. After 24 hours, the teeth were polished, thermocycled, and sealed with cosmetic varnish. The samples were then immersed in 2% methylene blue for four hours and sectioned in the buccolingual direction to determine the degree of microleakage.
  
  
  RESULTS
  After statistical analysis (Kruskal-Wallis, p<0.05), no significant differences were verified among the tested groups and between the evaluated cervical or incisal margins of the restoration.
  
  
  CONCLUSIONS
  The use of the chlorhexidine did not interfere with the adhesion process regardless of whether a CB or the Er:YAG laser were used to prepare class V cavities when restored with the tested self-etching adhesive system.
authors.affiliation: Department of Restorative Dentistry, University of Sao Paulo, Brazil. vinigmartins@yahoo.com
authors.forename: Vinicius R
authors.initials: VR
authors.lastname: Geraldo-Martins
authors.forename: Fabio R P
authors.initials: FR
authors.lastname: Robles
authors.forename: Adriana B
authors.initials: AB
authors.lastname: Matos
mesh_terms: D000818:Animals; D000891:Anti-Infective Agents, Local / Q000009:adverse effects*; D002417:Cattle; D002710:Chlorhexidine / Q000009:adverse effects*; D004396:Coloring Agents; D003188:Composite Resins; D003737:Dental Cavity Preparation / Q000295:instrumentation*; D003763:Dental Leakage / Q000175:diagnosis / Q000209:etiology / Q000517:prevention & control; D018772:Dental Marginal Adaptation; D003793:Dental Restoration, Permanent / Q000379:methods; D017220:Dentin-Bonding Agents; D004871:Erbium; D053685:Laser Therapy; D008751:Methylene Blue; D008855:Microscopy, Electron, Scanning; D019279:Resin Cements; D012822:Silicon Dioxide; D015040:Zirconium
chemical_list: D000891:Anti-Infective Agents, Local; C438313:Clearfil SE Bond; D004396:Coloring Agents; D003188:Composite Resins; D017220:Dentin-Bonding Agents; D019279:Resin Cements; C083568:Z100 composite resin; D012822:Silicon Dioxide; D004871:Erbium; D015040:Zirconium; D002710:Chlorhexidine; D008751:Methylene Blue