الفهرس 
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Abstract
The ceramic surface is traditionally subjected to a superficial treatment known as glazing; the glazing treatment seals the open pores on its surface after firing process which provides excellent optical properties, esthetics and greater surface smoothness.
At the time of the delivery of a ceramic restoration, the adjustment of a restoration remove the glazed layer and can roughen the occluding surface and causing abrasion on the adjacent teeth and on other restorative materials in the opposing arch, in addition to promoting biofilm retention and affecting the surface roughness of the ceramic restoration.
Intra oral finishing and polishing of dental ceramic restorations could decrease the roughness and abrasiveness done by adjustments of ceramic restoration.
Aim of the study was to evaluate the effect of finishing and polishing on color and surface roughness of three ceramic materials after adjustments.
Materials and methods: 24 ceramic samples were prepared from three types of ceramics, lithium disilicate Emax CAD, Bruxizer monolithic zirconia and Lava Ultimate CAD (n=8). Emax CAD and bruxizer group samples were glazed while lava ultimate group samples were polished according to manufacturer advice then all samples were subjected to color and surface roughness analysis. All samples are subjected to grinding by a wheel diamond stone simulating the occlusal adjustment in clinical condition mounted on a straight hand piece motor in surveyor device to standardize the adjustments of all samples. All the samples of the three ceramic materials were finished and polished after being adjusted according to manufacturer advice.
All adjusted samples were subjected to color analysis using spectrophotometer and surface roughness using profilometer.
Color difference between two readings of samples is obtained by the equation:
∆E=√((∆L)²+(∆a)^2+(∆b)²)
where ΔE is the color difference.
L. is a measure of the Lightness of an object, ranging from 0 (Black) to 100 (White).
a is a measure of redness (a > 0) or greenness (a < 0).
b is a measure of yellowness (b > 0) or blueness (b < 0).
The surface roughness results of all samples obtained from profilometer (Ra values) are collected to evaluate the difference between unadjusted samples and adjusted samples.
Results showed lower surface roughness Ra values of adjusted and polishing samples than the glazed unadjusted samples, the polishing methods can result in as smooth or smoother surface than glazing of ceramics. Color analysis showed that the clinical methods of polishing resulted in acceptable color difference in comparison with the glazed samples.