Title: Surface Roughness of Polymer Infiltrated and Pressable Ceramics on Enamel
Yehia Aboushady (Presenter)
Faculty of Dentistry Alexandria University
Objectives: The purpose of this study is to evaluate and correlate the surface roughness changes of polymer infiltrated ceramic (Vita Enamic) and pressable lithium disilicate based ceramic (IPS e.max press) on human enamel.
Methods: Two-body wear test was conducted in custom made tooth wear brushing machine (60,000 cycles, 20N and 60 cycle/min). The test specimens were divided into two groups, group1 (n=16) consisted of 8 Vita Enamic ceramic specimens and 8 enamel cusp antagonists and group2 (n=16) consisted of 8 IPS e.max press ceramic specimens and 8 enamel cusp antagonists. Surface roughness was measured before and after the wear test using a white light interference microscope. The data was collected and statistically analyzed using Mann-Whitney (U) test. Correlation analysis was performed between ceramic material surface roughness change and their natural enamel cusp antagonists. The wear pattern was evaluated qualitatively using scanning electron microscope.
Results: Statistical significant difference was detected for surface roughness changes in all samples after wear testing (P< 0.05).Vita Enamic showed lower surface roughness change with a mean value of (0.06 ± 0.03µm) . IPS e.max press samples showed a mean value of(0.15±0.10µm) .Less surface roughness change in enamel cusp antagonists was measured when opposed to Vita Enamic samples (0.06 ± 0.08 µm). The correlation analysis revealed that the mean change of surface roughness between Vita Enamic and enamel cusp antagonist showed a weak negative relation , while the mean change in the IPS e.max press and enamel cusp antagonist showed a strong positive relation.
Conclusions: Vita Enamic revealed lower surface roughness change than IPS e.max press and thus contributed to lower surface roughness change in enamel cusp antagonist.