Effects of residual water on microtensile bond strength of onebottle dentin adhesive systems with different solvent bases

• Published in: Chinese medical journal Vol. 118; no. 19; pp. 1623 - 1628
• Main Author: ZHANG Zhi-xing HUANG Cui ZHENG Tie-li WANG Sa CHENG Xiang-rong
• Format: Journal Article
• Language: English
• Published: 2005
• Subjects: 干燥症状; 牙质黏合剂; 预防措施
• ISSN: 0366-6999; 2542-5641

Background The wet-bonding technique is recommended for the one-bottle dentin adhesive systems, but the moisture concept varies widely among the instructions of manufacturers as well as among investigators. The aim of this study was to evaluate the effects of different dentin surface moisture on the microtensile bond strength （s） of an ethanol/water-based adhesive system and an acetone-based system to dentin. Methods Forty intact human premolars extracted for orthodontic reasons were used. Superficial occlusal flat dentin surfaces of these premolars were exposed, finished with wet 600-grit silicon carbide paper. Under four wet and dry conditions （overwet, blot dry, one-second dry and desiccated）, resin composite was bonded to dentin by using Single Bond （SB） or Prime ＆ Bond NT （PB） according to the manufacturers＇ instructions. The teeth were longitudinally sectioned in the “x” and “y” directions to obtain bonded beams with a cross-sectional area of 0. 81 mm^2 with a slow-speed diamond saw. The bonded specimens were tested in tension at a crosshead speed of 1 mm/min until failure of the bonds. Failure modes were observed with a scanning electron microscope. The mean bond strengths were analyzed by one-way ANOVA and Turkey＇s test. Results The bond strength of the overwet/SB, blot dry/SB, one-second dry/SB and desiccated/SB groups was 10.87 MPa, 22.47 MPa, 24.91 MPa and 12. 99 MPa, respectively. The bond strength of the overwet/PB, blot dry/PB, one-second dry/PB and desiccated/PB groups was 10.02 MPa, 20. 67 MPa, 21.82 MPa and 10. 09 MPa, respectively. For both SB and PB, the blot dry group and one-second dry group revealed significantly higher bond strengths than the overwet and desiccated groups （P 〈0.05）. Conclusions In order to achieve the highest bond strength to dentin, keeping appropriately moist condition is critical for the one-bottle dentin adhesive systems with solvent. the dentin surface in an ethanol/water or acetone