title: Bond strength to primary tooth dentin following disinfection with a chlorhexidine solution: an in vitro study.
abstract: OBJECTIVE
  The aim of this study was to determine the effect on shear bond strength of chlorhexidine used as a cavity disinfectant on primary tooth dentin.
  
  
  METHODS
  Thirty specimens were randomly divided into 3 groups (N = 10) and treated as follows: (1) in Group I, the dentin was acid etched with a 37% phosphoric acid for 15 seconds, washed and dried; (2) in Group II, a 2% commercial chlorhexidine solution (Cav Clean) was applied for 40 seconds, washed and dried following acid etching for 15 seconds; and (3) in Group III, dentin was treated with a 37% phosphoric acid gel containing 2% digluconate of chlorhexidine (Cond AC) for 15 seconds. In all specimens, the adhesive Single Bond (3M) was applied, and composite cylinders (Filtek Z 250) were built. The specimens were sheared with a universal testing machine (Instron) running at a crosshead speed of 0.5 mm/min, and the results calculated in MPa. The specimens were also observed to record the failure mode.
  
  
  RESULTS
  ANOVA analysis revealed that the shear bond strength of Group II (17.99+1.15 MPa) was significantly lower than Group I (19.88+1.02 MPa) and Group III (19.57+1.02 MPa). After debonding, 63% of the specimens presented cohesive failure of the material, 24% adhesive failure and 10% cohesive failure of dentin.
  
  
  CONCLUSIONS
  The commercial cavity disinfectant containing 2% chlorhexidine had an adverse effect on Single Bond and produced significantly lower shear bond strength than the etch gel with chlorhexidine and the acid etch alone.
authors.affiliation: Pediatric Dentistry Division, Santa Catarina Federal University, Florianópolis, Brazil. rvieira@ccs.ufsc.br
authors.forename: Ricardo de Sousa
authors.initials: Rde S
authors.lastname: Vieira
authors.forename: Ivo Alves
authors.initials: IA
authors.lastname: da Silva
mesh_terms: D000134:Acid Etching, Dental; D000268:Adhesiveness; D000704:Analysis of Variance; D000891:Anti-Infective Agents, Local / Q000627:therapeutic use*; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D002710:Chlorhexidine / Q000031:analogs & derivatives* / Q000627:therapeutic use*; D003188:Composite Resins / Q000737:chemistry; D001840:Dental Bonding; D003737:Dental Cavity Preparation; D003793:Dental Restoration, Permanent; D003804:Dentin / Q000648:ultrastructure*; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D004203:Disinfection; D006801:Humans; D010756:Phosphoric Acids / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D014094:Tooth, Deciduous / Q000648:ultrastructure*
chemical_list: D000891:Anti-Infective Agents, Local; D003188:Composite Resins; D017220:Dentin-Bonding Agents; C444701:Filtek Z250; D010756:Phosphoric Acids; C115612:single bond; D017438:Bisphenol A-Glycidyl Methacrylate; C010882:chlorhexidine gluconate; D002710:Chlorhexidine