Design, characterization and evaluation of biomimetic polymeric dental composites with remineralization potential pp.281-318
Authors: (D. Skrtic and J.M. Antonucci, Paffenbarger Research Center, American Dental Association Foundation, National Institute of Standards and Technology, Gaithersburg, and others)
Abstract: During the last century, much has been learned about the process of dental caries, a localized destruction of tooth tissue by plaque microorganisms that ferment dietary carbohydrates into organic acids which then cause dissolution of tooth mineral. Teeth are constantly going through cycles of mineral loss (when oral pH is below the point at which tooth mineral begins to dissolve) and repair (neutral and/or basic pH conditions that favor the redeposition of mineral). The net loss or gain in mineral over time ultimately determines whether tooth decay (demineralization) will advance, stabilize and/or regress. The major goal of clinical intervention is the preservation of tooth structure and the prevention of lesion progression to the point where restoration is needed. Caries prevention strategies have focused on reducing bacterial growth, neutralizing oral acids and using various remineralizing agents. Traditionally, remineralizing caries-arresting approaches are based on calcium and phosphate ion delivery through the use of dentifrices, chewing gums and mouthwashes, and systemic and/or topical fluoridation. However, restoring the lost mineral by using remineralization solutions containing calcium and phosphate ions often fails clinically because of the low solubility of calcium phosphates, particularly in the presence of fluoride ions and their inability to incorporate into plaque and localize at the tooth surface . Incorporation of fluoride into dental materials is viewed by many as the scientific cornerstone for caries prevention [2-14]. It is generally recognized that fluoride regenerates damaged tooth enamel via incorporation in tooth mineral as fluoroapatite or fluoride-enriched hydroxyapatite, therefore decreasing the solubility of tooth enamel. Fluoride has been less effective as dentin remineralizing vehicle [2, 11, 13, 14]. In addition to the various fluoride treatments, remineralization of enamel has been successfully achieved by two distinct new technologies: a) casein-phosphopeptide stabilized amorphous calcium phosphate (ACP) in the form of mouthrinses and sugar-free chewing gums [15-17] and b) ACP based polymeric composites [18-20]. Dental applications of ACP also include varnishes, dentifrices and desensitizing agents [21-24]. The development of the ACP based remineralizing composites is discussed in this Chapter with emphasis on the structure-composition-property relationships and comprehensive physicochemical evaluation of composites formulated for various dental applications.