Estudos do efeito anticárie de materiais odontológicos beneficiados por nanotecnologia

Abstract

The application of nanotechnology in dentistry can promote the optimization of aesthetic and mechanical characteristics of dental materials as well as provide an anticaries action due to the lowest oral biofilm accumulation on these materials and release of antimicrobial or remineralizing compounds. The objectives of each chapter are: 1) to review the literature concerning the use of nanoparticles in dental materials with direct or indirect implications for the control of caries lesions (chapter 1), 2) to investigate in vitro the fluoride release and the inhibitory potential of nanoparticulated fluoridated orthodontic cement on demineralization of enamel (chapter 2), 3) to study the in situ effect of nanoparticle composite containing fluoride on fluoride release and the inhibition of enamel demineralization (chapter 3) 4) to evaluate the effect of incorporation of silver nanoparticles (NAg) and amorphous calcium phosphate (NACP) in commercial adhesive system (chapter 4), 5) to evaluate the effect of incorporation monomer associated with quaternary ammonium (QADM), NAg and NACP in experimental adhesive system (chapter 5) and 6) to study the in situ effect of composite resin containing NACP on the oral biofilm and enamel caries lesions (chapter 6). As methodology approaches a literature review, 3 in vitro studies with microbiological caries model and 2 in situ studies were performed according to the cited objectives. As results, the developing anticaries nanomaterials still need a better understanding of the action mechanisms, safety and efficacy of nanoparticles (chapter 1). Fluoride release and the enamel demineralization inhibition of the nanoparticulated fluoridated orthodontic cement were lower than that shown by resin-modified glass ionomer cement (chapter 2). Nanoparticle-containing composite showed little in situ anticaries activity without prejudice to its surface roughness (chapter 3). The inclusion of NAG and NACP in adhesive system showed significant in vitro antimicrobial effect without decreasing bond strength when compared to control (chapter 4). Metabolic activity, lactic acid production and number of colony forming units were lower in biofilms formed on experimental adhesive systems containing QADM, Nag and NACP without decreased bond strength when compared to control (chapter 5). NACP composite released more calcium and phosphorus in cariogenic biofilm formed in situ and caused shallow caries lesions on enamel around the restorations that the control composite (chapter 6). In summary, the presence of nanoparticles fillers as basic composition of dental materials does not assure effective anticaries activity. Incorporating QADM, Nag and NACP in dental materials can promote anticaries effect, and showing as a promising approach in dental materials development.