Roberto Pinna1, Paolo Usai1, Enrica Filigheddu1, Franklin Garcia-Godoy2,3, Egle Milia1. 1. Department of Biomedical Science, University of Sassari, Sassari, Italy. 2. Department of Bioscience Research, College of Dentistry, University of Tennessee Health Science Center, Memphis, Tennessee, USA. 3. The Forsyth Institute, Cambridge, Massachusetts, USA.
Abstract
PURPOSE: To critically discuss adhesive materials and oral cariogenic biofilm in terms of their potential relevance to the failures of adhesive restorations in the oral environment. METHODS: The literature regarding adhesive restoration failures was reviewed with particular emphasis on the chemistry of adhesive resins, weakness in dentin bonding, water fluids, cariogenic oral biofilm and the relations that influence failures. Particular attention was paid to evidence derived from clinical studies. RESULTS: There was much evidence that polymerization shrinkage is one of the main drawbacks of composite formulations. Stress results in debonding and marginal leakage into gaps with deleterious effects in bond strength, mechanical properties and the whole stability of restorations. Changes in resins permit passage of fluids and salivary proteins with a biological breakdown of the restorations. Esterases enzymes in human saliva catalyze exposed ester groups in composite producing monomer by-products, which can favor biofilm accumulation and secondary caries. Adhesive systems may not produce a dense hybrid layer in dentin. Very often this is related to the high viscous solubility and low wettability in dentin of the hydrophobic BisGMA monomer. Thus, dentin hybrid layer may suffer from hydrolysis using both the Etch&Rinse and Self-Etching adhesive systems. In addition, exposed and non-resin enveloped collagen fibers may be degraded by activation of the host-derived matrix metalloproteinase. Plaque accumulation is significantly influenced by the surface properties of the restorations. Biofilm at the contraction gap has demonstrated increased growth of Streptococcus mutans motivated by the chemical hydrolysis of the adhesive monomers at the margins. Streptococcus mutans is able to utilize some polysaccharides from the biofilm to increase the amount of acid in dental plaque with an increase in virulence and destruction of restorations. Stability of resin restorations in the oral environment is highly dependent on the structure of the monomers used in composite and adhesive systems. Still, the issues related to microleakage of fluids into the gap and bacteria leaching from the surface of composites represent the main causes of failure of adhesive restorations. CLINICAL SIGNIFICANCE: Modifications of adhesive materials are necessary to address their instability in the oral environment.
PURPOSE: To critically discuss adhesive materials and oral cariogenic biofilm in terms of their potential relevance to the failures of adhesive restorations in the oral environment. METHODS: The literature regarding adhesive restoration failures was reviewed with particular emphasis on the chemistry of adhesive resins, weakness in dentin bonding, water fluids, cariogenic oral biofilm and the relations that influence failures. Particular attention was paid to evidence derived from clinical studies. RESULTS: There was much evidence that polymerization shrinkage is one of the main drawbacks of composite formulations. Stress results in debonding and marginal leakage into gaps with deleterious effects in bond strength, mechanical properties and the whole stability of restorations. Changes in resins permit passage of fluids and salivary proteins with a biological breakdown of the restorations. Esterases enzymes in human saliva catalyze exposed ester groups in composite producing monomer by-products, which can favor biofilm accumulation and secondary caries. Adhesive systems may not produce a dense hybrid layer in dentin. Very often this is related to the high viscous solubility and low wettability in dentin of the hydrophobic BisGMA monomer. Thus, dentin hybrid layer may suffer from hydrolysis using both the Etch&Rinse and Self-Etching adhesive systems. In addition, exposed and non-resin enveloped collagen fibers may be degraded by activation of the host-derived matrix metalloproteinase. Plaque accumulation is significantly influenced by the surface properties of the restorations. Biofilm at the contraction gap has demonstrated increased growth of Streptococcus mutans motivated by the chemical hydrolysis of the adhesive monomers at the margins. Streptococcus mutans is able to utilize some polysaccharides from the biofilm to increase the amount of acid in dental plaque with an increase in virulence and destruction of restorations. Stability of resin restorations in the oral environment is highly dependent on the structure of the monomers used in composite and adhesive systems. Still, the issues related to microleakage of fluids into the gap and bacteria leaching from the surface of composites represent the main causes of failure of adhesive restorations. CLINICAL SIGNIFICANCE: Modifications of adhesive materials are necessary to address their instability in the oral environment.
Authors: Sasikumar Ponnusamy; Hanan H Ali; Felisha Dutt; Saeed Ur Rahman; Ahmad A Salah; Mahek Pipalia; Robert E Baier; Praveen R Arany Journal: Sci Rep Date: 2022-05-11 Impact factor: 4.996
Authors: Paolo Usai; Vincenzo Campanella; Giovanni Sotgiu; Giovanni Spano; Roberto Pinna; Stefano Eramo; Laura Saderi; Franklin Garcia-Godoy; Giacomo Derchi; Giorgio Mastandrea; Egle Milia Journal: Nanomaterials (Basel) Date: 2019-12-09 Impact factor: 5.076
Authors: Justyna Mazurek-Popczyk; Adam Nowicki; Katarzyna Arkusz; Łukasz Pałka; Anna Zimoch-Korzycka; Katarzyna Baldy-Chudzik Journal: BMC Oral Health Date: 2022-10-13 Impact factor: 3.747