Characterization of Dentine to Assess Bond Strength of Dental Composites

Materials

Saad Liaqat²  Anas Aljabo²  Muhammad Adnan Khan²  Hesham Ben Nuba²  Laurent Bozec²  Paul Ashley¹  Anne Young² 

[1] Department of Paediatric Dentistry, UCL Eastman Dental Institute, 256 Gray’s Inn Road, London WC1X 8LD, UK; E-Mail:;Division of Biomaterials and Tissue Engineering, UCL Eastman Dental Institute, 256 Gray’s Inn Road, London WC1X 8LD, UK; E-Mails:

关键词: dental composite;    dentine;    4-META;    self-adhesive;    hydroxyapatite;    collagen;    micro-gap;   

DOI  :  10.3390/ma8052110

来源: mdpi

【 摘 要 】

This study was performed to develop alternating dentine adhesion models that could help in the evaluation of a self-bonding dental composite. For this purpose dentine from human and ivory was characterized chemically and microscopically before and after acid etching using Raman and SEM. Mechanical properties of dentine were determined using 3 point bend test. Composite bonding to dentine, with and without use of acid pre-treatment and/or the adhesive, were assessed using a shear bond test. Furthermore, micro gap formation after restoration of 3 mm diameter cavities in dentine was assessed by SEM. Initial hydroxyapatite level in ivory was half that in human dentine. Surface hydroxyapatites decreased by approximately half with every 23 s of acid etch. The human dentine strength (56 MPa) was approximately double that of ivory, while the modulus was almost comparable to that of ivory. With adhesive use, average shear bond strengths were 30 and 26 MPa with and without acid etching. With no adhesive, average bond strength was 6 MPa for conventional composites. This, however, increased to 14 MPa with a commercial flowable “self–bonding” composite or upon addition of low levels of an acidic monomer to the experimental composite. The acidic monomer additionally reduced micro-gap formation with the experimental composite. Improved bonding and mechanical properties should reduce composite failures due to recurrent caries or fracture respectively.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.