OBJECTIVES: To analyze the effects of different surface moisture on bond strength (BS) durability of an ethanol/water based, Single Bond (SB); an acetone-based, One-Step (OS); and a water-based, Syntac Single Component (SC) adhesive system to dentin. METHODS: Forty-five human third molars had their superficial dentin surface exposed flat by abrasion. The adhesives were applied to a delimited area of 52 mm(2) on either air-dried (30 s) or rewetted surfaces (2.5 or 4.0 microl) followed by resin composite build-ups. After storage in water at 37 degrees C (24 h), the teeth were sectioned to obtain bonded sticks with a cross-sectional area of 0.8 mm(2). The sticks, from each tooth, were divided, stored in water at 37 degrees C and tested either immediately or after 6 months (6 M) at 0.5 mm/min. BS was expressed as an index that considers cohesive failures and estimated values of premature debonded specimens. RESULTS: Three-way ANOVA showed statistically significant effects for moisture degree, storage time and double interactions (p < 0.05). While SB and SC achieved higher BS at 0 and 2.5 microl of water, for OS the BS was higher at 4.0 microl of water. Regardless of the moisture degrees, reductions in BS were observed after 6 M storage for SB and OS (p < 0.05), but not for SC (p > 0.05). No difference in BS between the 24 h and 6 M storage was found when the moisture was set at the extreme conditions. Significant reduction in BS was observed when the moisture was set at 2.5 microl. SIGNIFICANCE: The bond strength of different solvent-based adhesive systems gradually decreases over time, regardless of the variable moisture pattern used for the bonding procedure.
OBJECTIVES: To analyze the effects of different surface moisture on bond strength (BS) durability of an ethanol/water based, Single Bond (SB); an acetone-based, One-Step (OS); and a water-based, Syntac Single Component (SC) adhesive system to dentin. METHODS: Forty-five human third molars had their superficial dentin surface exposed flat by abrasion. The adhesives were applied to a delimited area of 52 mm(2) on either air-dried (30 s) or rewetted surfaces (2.5 or 4.0 microl) followed by resin composite build-ups. After storage in water at 37 degrees C (24 h), the teeth were sectioned to obtain bonded sticks with a cross-sectional area of 0.8 mm(2). The sticks, from each tooth, were divided, stored in water at 37 degrees C and tested either immediately or after 6 months (6 M) at 0.5 mm/min. BS was expressed as an index that considers cohesive failures and estimated values of premature debonded specimens. RESULTS: Three-way ANOVA showed statistically significant effects for moisture degree, storage time and double interactions (p < 0.05). While SB and SC achieved higher BS at 0 and 2.5 microl of water, for OS the BS was higher at 4.0 microl of water. Regardless of the moisture degrees, reductions in BS were observed after 6 M storage for SB and OS (p < 0.05), but not for SC (p > 0.05). No difference in BS between the 24 h and 6 M storage was found when the moisture was set at the extreme conditions. Significant reduction in BS was observed when the moisture was set at 2.5 microl. SIGNIFICANCE: The bond strength of different solvent-based adhesive systems gradually decreases over time, regardless of the variable moisture pattern used for the bonding procedure.
Authors: Adriana Pigozzo Manso; Rosa Helena Miranda Grande; Ana Karina Bedran-Russo; Alessandra Reis; Alessandro D Loguercio; David Henry Pashley; Ricardo Marins Carvalho Journal: Dent Mater Date: 2014-05-09 Impact factor: 5.304