The pursuit of resin-dentin bond durability : simultaneous enhancement of collagen structure and polymer network formation in hybrid layers
Stape, Thiago Henrique Scarabello; Mutluay, Mustafa Murat; Tjäderhane, Leo; Uurasjärvi, Emilia; Koistinen, Arto; Tezvergil-Mutluay, Arzu (2021-04-15)
Stape, T. H. S., Mutluay, M. M., Tjäderhane, L., Uurasjärvi, E., Koistinen, A., & Tezvergil-Mutluay, A. (2021). The pursuit of resin-dentin bond durability: Simultaneous enhancement of collagen structure and polymer network formation in hybrid layers. Dental Materials, 37(7), 1083–1095. https://doi.org/10.1016/j.dental.2021.03.010
© 2021 The Author(s). Published by Elsevier Inc. on behalf of The Academy of Dental Materials. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
https://creativecommons.org/licenses/by-nc-nd/4.0/
https://urn.fi/URN:NBN:fi-fe2021070541132
Tiivistelmä
Abstract
Objective:Imperfect polymer formation as well as collagen’s susceptibility to enzymatic degradation increase the vulnerability of hybrid layers over time. This study investigated the effect of new dimethyl sulfoxide (DMSO)-containing pretreatments on long-term bond strength, hybrid layer quality, monomer conversion and collagen structure.
Methods:H₃PO₄-etched mid-coronal dentin surfaces from extracted human molars (n = 8) were randomly treated with aqueous and ethanolic DMSO solutions or following the ethanol-wet bonding technique. Dentin bonding was performed with a three-step etch-and-rinse adhesive. Resin-dentin beams (0.8 mm²) were stored in artificial saliva at 37 °C for 24 h and 2.5 years, submitted to microtensile bond strength testing at 0.5 mm/min and semi-quantitative SEM nanoleakage analysis (n = 8). Micro-Raman spectroscopy was used to determine the degree of conversion at different depths in the hybrid layer (n = 6). Changes in the apparent modulus of elasticity of demineralized collagen beams measuring 0.5 × 1.7 × 7 mm (n = 10) and loss of dry mass (n = 10) after 30 days were calculated via three-point bending and precision weighing, respectively.
Results:DMSO-containing pretreatments produced higher bond strengths, which did not change significantly over time presenting lower incidence of water-filled zones. Higher uniformity in monomer conversion across the hybrid layer occurred for all pretreatments. DMSO-induced collagen stiffening was reversible in water, but with lower peptide solubilization.
Significance:Improved polymer formation and higher stability of the collagen-structure can be attributed to DMSO’s unique ability to simultaneously modify both biological and resin components within the hybrid layer. Pretreatments composed of DMSO/ethanol may be a viable-effective alternative to extend the longevity of resin-dentin bonds.
Kokoelmat
- Avoin saatavuus [32049]