Abstract
The bond strength of light-cured composite resin with a bonding agent, which contained 2-methacryloxyethyl hydrogen maleate to dentin treated with 37% phosphoric acid solution(PA solution)and 10% citric acid-3% ferric chloride solution(10-3 solution)was measured after being immersed in water for 1 day, 1 month, 3 months, 6 months and 1year to investigate the influence of water on bonding.The bond strength to dentin treated with a PA solution did not change with the time spent immersed in water up to 6 months, but significantly decreased with any further increases in time.For 10-3 solution, the bond strength did not change with time.The bonding agent created an acid-proof dentin layer with different thickness on the treated dentin surfaces as observed by SEM.The layer thickness was about 5μm for PA solution and about 2μm for the 10-3 solution.When treatment with PA solution was used, the SEM of 1-day-old specimens after the bond test revealed resin-dentin interface failure and superficial dentin cohesive fracture.The 1-year-old specimens had resin cohesive fracture, dentin cohesive fracture and resin-dentin interface failure.When the treatment with 10-3 solution was used, the SEM of 1-day-old specimens revealed resin-dentin interface failure and superficial dentin cohesive fracture.The 1-year-old specimens showed resin cohesive fracture, superficial dentin cohesive fracture and resin-dentin interface failure.
