Análise dos efeitos de diferentes agentes químicos enzimáticos à base de papaína nas propriedades físico-mecânicas e químicas dos tecidos dentais humanos e na atividade antimicrobiana

Abstract

Enzymatic chemical agents (ECAs) are papain-based materials used in the selective removal of carious dentin tissue. Although they have been on the market for over two decades, their popularization in clinical practice is still debated in the literature. ECAs can be presented as an alternative therapy to conventional removal with rotary instruments for those patients with fear, phobia, hypersensitivity to sensory stimuli produced in the dental office (noise, thermal sensations, taste, tactile pressure, among others) and mainly because they allow the dentist to maintain the dentin tissue undenatured, which reduces the risk of pulp exposure and consequently avoids endodontic interventions. Due to their commercial presentation, the professional may have difficulty in restricting the application to the back wall, filling the cavity completely, allowing the material to also interact with the dental tissues present in the surrounding wall. Studies evaluating the behavior of ECAs on healthy human dental tissues, as well as their antimicrobial effect, are still limited in the literature. This thesis aimed to characterize different papain-based ECAs and investigate their effect on the physical-mechanical and chemical properties of healthy human dental tissues and their behavior in controlling microorganisms. In this context, this thesis produced four chapters in order to fill the gaps present in the literature on ECAs regarding their pH (n=10), microhardness (n=10), characterization of the enamel and dentin surface (n=3), dentin chemical alteration by ATR/FTIR (n=6), wettability (n=6), sensitivity and formation of microbial colonies (n=9) and clinical applicability for patients with sensory processing disorder. The findings of this thesis allow us to infer that, although the ECAs present acidity, they do not reduce the microhardness of enamel and dentin, but modify their surface as well as their chemical composition of dentin without compromising the tissue, increase the dentin surface contact energy with water and act in the control of Streptococcus mutans, but limited on Candida albicans.