Evaluation of Enamel Surface Morphology and Microhardness after the Application of Different Protective Agents

Abstract

The aim of this in vitro study was to compare the eff ect of diff erent protective agents on the surface microhardness and morphology on enamel eroded by a cola drink. Sixty sound anterior teeth were randomly divided into fi ve groups. The baseline surface microhardness of the enamel was measured. For demineralization procedures, all teeth were immersed in cola for 8 minutes and surface microhardness was remeasured. The fi ve groups for remineralization procedures were defi ned as: Group 1: Artifi cial saliva, Group 2: 1.23% Acidulated Phosphate Fluoride gel (APF), Group 3: 5% NaF varnish, Group 4: Casein Phosphopeptide-Amorphous Calcium Phosphate (CPP-ACP), and Group 5: Probiotic yogurt. After each experimental procedure, a third microhardness measurement was repeated. Surface morphological changes were observed using SEM. All data were recorded for each group and statistically analyzed using two-way analysis of variance and one-way repeatedmeasures analysis of variance. All tests were performed at a signifi cance level of p < 0.05. No signifi cant diff erences for baseline microhardness values were found (P> 0.05). The mean surface microhardness in all groups decreased signifi cantly after immersion in cola (P< 0.05). After remineralization, NaF varnish and APF gel significantly increased the surface microhardness values. There were no signifi cant increases in the surface microhardness values of artifi cial saliva, CPP-ACP and probiotic yogurt. This study concludes that NaF varnish is more eff ective in re-hardening of eroded enamel.

Effect of Three Treatment Modalities for White Spot Enamel Lesions on Enamel Surface Roughness and Micro-Hardness

“…They attributed their finding to the ability of the low-viscosity resin to fill the spaces between the remaining crystals of the porous lesions and re-harden the demineralized tissue, thereby improving their mechanical strength. Also, this result is in disagreement with Simsek, et al, (20) who found there were no significant increases in the surface microhardness values of artificial saliva or CPP-ACP. They attributed their findings to CCP-ACP being more effective in deep caries lesions.…”

Effect of topical fluoride applications on residual monomer release from resin-based restorative materials

“…However, whether resin composites exposed to these agents cause surface degradation has been a matter of concern. Researchers have investigated whether these agents, which are applied for protective purposes in dentistry, cause surface changes such as surface roughness, microhardness, and elemental changes in resin-based composites [ 4 , 42 – 44 ]. Since APF gels contain strong acids, the composition and surface integrity of composites and other glass-containing restoratives can change significantly.…”