Protective effect of protein-rich modified pellicle against erosive and cariogenic challenges

Abstract

Dental caries and erosion are the most common dental lesions, caused by acids. Therefore it is rational, as well as using preventive measures, to develop oral products that influence the progression of them. Despite differences in etiology, for both diseases, one of the main parameters is saliva that possesses several natural biological properties to protect tooth surfaces against demineralization, including the formation of the acquired pellicle. The acquired pellicle is a biofilm, free of bacteria, covering oral hard and soft tissues. It is composed of mucins, glycoproteins and proteins, among which are several enzymes. Enzymes are key components of the pellicle with high relevance for its protective properties. Since the addition of proteins to toothpaste shows some promise for the prevention of erosion, the focus of this study will be to assess the effect of protein-containing toothpastes, with different concentrations on protection of enamel and dentin wear in dental caries and erosion challenges. The objective of this proposal is to investigate the impact of salivary pellicle and proteins on enamel and dentin protection from acid challenges, together with monitoring the effects of potential materials that can modify the pellicle protective properties. For that, bovine enamel and dentin specimens will be prepared and treated as follow (n=15): saliva (control); deionized water (negative control); saliva + a mixture of 0.27% mucin and 0.5% casein solution; 0.025 ¼g/¼L canecystatin-5 solution; toothpaste with high-protein content (Zendium Acid Defence; a commercially available toothpaste with 0.21% w/w proteins: amyloglucosidase, glucose oxidase, lactoperoxidase, lysozyme, lactoferrin, IgG and casein); saliva + toothpaste with high-protein content (Zendium Acid Defence); saliva + toothpaste with high-protein content (Zendium Acid Defence) + 0.025 ¼g/¼L canecystatin-5. Subsequent exposure to acid challenges and analysis for calcium concentration in the solutions will indicate the relative protection of the treatments. After that, enamel and dentin demineralization and remineralization will be monitored using surface Microhardness (SMH) and Quartz Crystal Microbalance measurements. (AU)