Journal article
Removal of water binding proteins from dentin increases the adhesion strength of low-hydrophilicity dental resins
Dental materials, Vol.36(10), pp.e302-e308
10/2020
DOI: 10.1016/j.dental.2020.07.004
PMID: 32811665
Abstract
•Proteoglycans are tightly bound to collagen acting as a barrier for infiltration of dental resin monomers.•Trypsin digestion removed PGs resulting in altered water balance and surface wettability of the dentin matrix.•Low hydrophilicity dental adhesives can effectively bond to dentin depleted of PGs.
To investigate the role of proteoglycans (PGs) on the physical properties of the dentin matrix and the bond strength of methacrylate resins with varying hydrophilicities.
Dentin were obtained from crowns of human molars. Enzymatic removal of PGs followed a standard protocol using 1 mg/mL trypsin (Try) for 24 h. Controls were incubated in ammonium bicarbonate buffer. Removal of PGs was assessed by visualization of glycosaminoglycan chains (GAGs) in dentin under transmission electron microscopy (TEM). The dentin matrix swelling ratio was estimated using fully demineralized dentin. Dentin wettability was assessed on wet, dry and re-wetted dentin surfaces through water contact angle measurements. Microtensile bond strength test (TBS) was performed with experimental adhesives containing 6% HEMA (H6) and 18% HEMA (H18) and a commercial dental adhesive. Data were statistically analyzed using ANOVA and post-hoc tests (α = 0.05).
The enzymatic removal of PGs was confirmed by the absence and fragmentation of GAGs. There was statistically significant difference between the swelling ratio of Try-treated and control dentin (p < 0.001). Significantly lower contact angle was found for Try-treated on wet and dry dentin (p < 0.002). The contact angle on re-wet dentin was not recovered in Try-treated group (p = 0.9). Removal of PGs significantly improved the TBS of H6 (109% higher, p < 0.001) and H18 (29% higher, p = 0.002) when compared to control. The TBS of commercial adhesive was not affected by trypsin treatment (p = 0.9).
Changing the surface energy of dentin by PGs removal improved resin adhesion, likely due to more efficient water displacement, aiding to improved resin infiltration and polymerization.
Details
- Title: Subtitle
- Removal of water binding proteins from dentin increases the adhesion strength of low-hydrophilicity dental resins
- Creators
- Ana Paula Farina - University of Illinois at ChicagoDoglas Cecchin - University of Illinois at ChicagoCristina M.P. Vidal - University of Illinois at ChicagoAriene Arcas Leme-Kraus - University of Illinois at ChicagoAna K. Bedran-Russo - University of Illinois at Chicago
- Resource Type
- Journal article
- Publication Details
- Dental materials, Vol.36(10), pp.e302-e308
- Publisher
- Elsevier Inc
- DOI
- 10.1016/j.dental.2020.07.004
- PMID
- 32811665
- ISSN
- 0109-5641
- eISSN
- 1879-0097
- Grant note
- DOI: 10.13039/501100002322, name: Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
- Language
- English
- Date published
- 10/2020
- Academic Unit
- Operative Dentistry
- Record Identifier
- 9984367654502771
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