The effect of a dental unit waterline treatment regimen on the shear bond strength of resin-based composite.
BACKGROUND
Numerous methods of disinfecting dental waterlines have been suggested. This study evaluates the effects of one disinfecting technique on the strength of resin-based composite's bond to enamel and to dentin.


METHODS
The authors bonded resin-based composite cylinders to enamel and dentin surfaces similarly mounted and prepared using three irrigation solutions. After undergoing acid etching, the tooth surface was rinsed with either distilled water, water from a municipal water source or a mixture of distilled water and mouthwash concentrate. The authors shear-tested the samples and analyzed the data statistically.


RESULTS
The group rinsed with distilled water mixed with mouthwash exhibited the lowest shear bond strengths. However, a one-way ANOVA indicated no statistically significant differences in the mean values among the treatment groups for either enamel (P = .295) or dentin (P = .393). Specimens bonded to enamel demonstrated primarily adhesive fracture at the tooth/composite interface. Those bonded to dentin showed a similar pattern, with some sites of cohesive fracture in the resin-based composite.


CONCLUSIONS
There was no significant difference in shear bond strengths of resin-based composite to tooth structure when rinsed with distilled water mixed with mouthwash, distilled water or water from a municipal source.


CONCLUSIONS
Dental unit waterlines disinfected using a diluted mouthwash solution may be used while bonding resin-based composite to either enamel or dentin.
Knight
J S
JS
Division of Operative Dentistry, Medical University of South Carolina College of Dental Medicine, 173 Ashley Ave., Charleston, S.C. 29425, USA. knightjs@musc.edu
Davis
S B
SB
McRoberts
J G
JG
D000134:Acid Etching, Dental; D000268:Adhesiveness; D000704:Analysis of Variance; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D003743:Dental Enamel / Q000648:ultrastructure; D003748:Dental Equipment; D003804:Dentin / Q000648:ultrastructure; D017220:Dentin-Bonding Agents / Q000737:chemistry; D004203:Disinfection; D006801:Humans; D009067:Mouthwashes / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D007507:Therapeutic Irrigation; D014867:Water / Q000737:chemistry; D018508:Water Purification
D003188:Composite Resins; D017220:Dentin-Bonding Agents; D009067:Mouthwashes; D014867:Water