Adhesion of restorative materials to the tooth structure has revolutionized the approach of dental treatment and is now essential for numerous elective dental procedures and for the replacement of tooth substance lost by caries or tooth fracture. Although there have been significant advances in dental adhesion technology, the contribution of dentin extracellular matrix (ECM) molecules to dentin bonding is still poorly understood. Fibrillar type I collagen is the predominant matrix component in dentin, and the maintenance of its fibrillar structure upon etching is crucial for the adhesion between restorative materials and dentin. The mechanisms for the maintenance of the structural integrity, however, are unknown. Based on our preliminary studies, we hypothesize that Chondroitin sulphate (CS-) and Keratan Sulphate (KS-) glycosaminoglycans (GAGs) carrying proteoglycans (PGs) facilitate dentin adhesion by maintaining the spatial architecture and stability of collagen fibrils. To address this hypothesis, the following specific aims are proposed: 1. To evaluate, after the dentin is demineralized, the effects of CS-, KS- or CS-KS removal on: 1a. Morphology of collagen fibrillar structure and collagen cross-linking analysis 1b. Ultimate strength of demineralized dentin and bond strength of adhesive resins 2. To determine, upon rewetting, the contribution of CS- and KS- GAGs/PGs by: 2a. Quantifying the levels of collagen re-expansion, collagen cross-linking analysis, and morphology of fibrillar structure, with and without CS, KS or both GAGs/PGs removal. 2b.Quantifying the UTS and bond strength with and without CS, KS or both GAGs/PGs removal 3. To determine the effects of CS- and KS-GAG addition on collagen re-expansion This combined biomechanical and biochemical approach may provide insights into the roles of CS/KS-PGs in collagen stabilization and dentin adhesion.

Agency
National Institute of Health (NIH)
Institute
National Institute of Dental & Craniofacial Research (NIDCR)
Type
Small Research Grants (R03)
Project #
1R03DE016116-01
Application #
6816009
Study Section
NIDCR Special Grants Review Committee (DSR)
Program Officer
Kousvelari, Eleni
Project Start
2004-07-01
Project End
2006-06-30
Budget Start
2004-07-01
Budget End
2005-06-30
Support Year
1
Fiscal Year
2004
Total Cost
$73,000
Indirect Cost
Name
University of North Carolina Chapel Hill
Department
Dentistry
Type
Schools of Dentistry
DUNS #
608195277
City
Chapel Hill
State
NC
Country
United States
Zip Code
27599
Reis, Andre F; Giannini, Marcelo; Pereira, Patricia N R (2008) Effects of a peripheral enamel bond on the long-term effectiveness of dentin bonding agents exposed to water in vitro. J Biomed Mater Res B Appl Biomater 85:10-7
Bedran-Russo, Ana Karina B; Pereira, Patricia N R; Duarte, Wagner R et al. (2008) Removal of dentin matrix proteoglycans by trypsin digestion and its effect on dentin bonding. J Biomed Mater Res B Appl Biomater 85:261-6
Pereira, P N R; Bedran-de-Castro, A K B; Duarte, W R et al. (2007) Removal of noncollagenous components affects dentin bonding. J Biomed Mater Res B Appl Biomater 80:86-91
Bedran-Russo, Ana Karina B; Pereira, Patricia N R; Duarte, Wagner R et al. (2007) Application of crosslinkers to dentin collagen enhances the ultimate tensile strength. J Biomed Mater Res B Appl Biomater 80:268-72
Reis, Andre F; Giannini, Marcelo; Pereira, Patricia N R (2007) Long-term TEM analysis of the nanoleakage patterns in resin-dentin interfaces produced by different bonding strategies. Dent Mater 23:1164-72
Reis, Andre F; Giannini, Marcelo; Pereira, Patricia N R (2007) Influence of water-storage time on the sorption and solubility behavior of current adhesives and primer/adhesive mixtures. Oper Dent 32:53-9
Reis, A F; Bedran-Russo, A K B; Giannini, M et al. (2007) Interfacial ultramorphology of single-step adhesives: nanoleakage as a function of time. J Oral Rehabil 34:213-21