Gradual dehydration affects the mechanical properties and bonding outcome of adhesives to dentin

• Published in: Dental Materials Journal Vol. 38; no. 3; pp. 361 - 367
• Main Authors: CHOWDHURY, A.F.M. Almas, SAIKAEW, Pipop, MATSUMOTO, Mariko, SANO, Hidehiko, CARVALHO, Ricardo M.
• Format: Journal Article
• Language: English
• Published: Japan The Japanese Society for Dental Materials and Devices 01-06-2019; Japanese Society for Dental Materials and Devices; Japan Science and Technology Agency
• Subjects: Adhesion tests; Adhesives; Bond strength; Bonding strength; Dehydration; Dentin; Dentistry; Elastic modulus; Hardness; Mechanical properties; Modulus of elasticity; Molars; Polymers; Resins; Storage; Teeth; Two-step self-etch adhesive; Variance analysis; Weight; Bond strength; Elastic modulus; Dehydration; Hardness; Two-step self-etch adhesive
• ISSN: 0287-4547; 1881-1361
• DOI: 10.4012/dmj.2018-142

This study evaluated the effects of dehydration on the mechanical properties of adhesive resins and dentin, and on the microtensile bond strength (µTBS) of adhesives. Third molars were randomly bonded with Clearfil Mega Bond (MB) or Clearfil SE Bond 2 (SE). After water-storage (37°C; 24 h), µTBS was obtained in ‘wet’ (tested after 5 min of removal from storage) and ‘dehydrated’ (tested after 10, 15 min and 24 h) conditions by a universal tester (crosshead speed: 1 mm/min). Data were analyzed by two-way ANOVA and Duncan’s test. Hardness (H), Elastic modulus (E) and weight-loss of dentin beams and adhesive-resin discs were also monitored over time and analyzed by one-way repeated measures ANOVA and Bonferroni’s test (α=0.05). Significant differences in bond strength were observed for adhesives and for conditions. Except for dentin’s E, dehydration caused significant gradual changes in the H, E and weight of adhesive resins and dentin (p<0.05).