Effects Of Erosive Degradation On Surface Of Esthetics Restorative Nanomaterials

Objectives: The aim of this study was to evaluate the erosive strength (roughness, hardness and morphology) of two resin-modified glass ionomer cements (Vitremer and Ketac N100) and two composite resins (Z350 and TPH Spectrum), when immerse in acidic solutions. Methods: Thirty discs of each material were prepared following the manufacturer's instruction, and polished after 24h. Then, Knoop hardness evaluations were carried out (baseline). Specimens were divided into 12 groups (n=10), according to the restorative material and storing solutions (artificial saliva, orange juice and Coca Cola). After 30 days of immersion, with weekly exchange the solution, surface was evaluated regarding roughness, hardness and morphology. Hardness and roughness data were submitted to the ANOVA and Tukey' tests (p<0.05). Results: Composites presented lower roughness and higher hardness than resin-modified glass ionomer materials in all studied situations. After erosion, significant decreasing on hardness was observed for all materials, while significant roughness increasing was observed in resin-modified glass ionomer materials depending on storing solution. While Vitremer had roughness increase, when only stored in orange juice, Ketac N100 was sensitive to Coca Cola and orange juice. Z350 composite showed similar values of hardness after erosion independent of storing solution. The other materials were less susceptible to saliva. Conclusion: The presences of nanofillers in studied esthetics restorative materials composition make the materials less susceptible to degradation.