Effect of a triclosan/copolymer/fluoride dentifrice prophylaxis on the shear bond strength of a composite resin to enamel.

A new fluoride dentifrice formulation containing triclosan and a copolymer has been introduced. The purpose of this study was to evaluate the shear bond strength of a resin composite bonded to enamel previously cleaned with this new dentifrice formulation. A total of 45 human extracted permanent molars were used. A flat enamel surface was obtained with 600 grit SiC paper and the teeth randomly distributed into 3 groups of 15 teeth each: Group 1: Pumice prophylaxis with a rubber cup and slow-speed handpiece; Group 2: Prophylaxis with a conventional fluoridated dentifrice (Colgate); Group 3: Prophylaxis with a triclosan/copolymer/NaF dentifrice (Colgate). After prophylaxis, the teeth were acid-etched with a 37% phosphoric acid gel for 30 seconds, rinsed and dried. An unfilled resin (Coe Bond) was thinly applied with a brush and cured for 30 seconds. A nylon ring was placed over the area and filled with a light-cured resin composite (Occlusin). The teeth were thermocycled for 100 cycles, mounted in plastic cups and plaster, and sheared with a knife-edged blade in an Instron running at a crosshead speed of 1 mm/min. The results in MPa were as follows: Group 1: 11.34 +/- 4.57; Group 2: 13.46 +/- 3.60; Group 3: 13.84 +/- 4.33. An ANOVA showed that there was no statistically significant difference among the groups. Fracture within the enamel occurred in 27% in Group 1, 47% in Group 2, and 67% in Group 3. The results support the use of the fluoride dentifrices tested in this study for prophylaxis prior to bonding procedures.