Influence of Simulated Gastric Juice on Surface Roughness, Morphology and Micro Hardness of CAD-CAM Materials (An In Vitro Study)
Author(s): Ghadeer S Abdulameer*, Mohammed R Hameed
Aim: The objective of this in vitro study was to evaluate the effect of the simulated gastric acid on surface roughness,
morphology and micro hardness of CAD/CAM ceramics and comparable with the immersion in the artificial saliva.
Materials and methods: A total of 160 sample were prepared (80 were observed for micro hardness with Vickers micro
hardness testing machine and the other 80 were observed for roughness with profile meter testing machine and surface
morphology changes with field emission scanning electron microscope). Each 80 samples were divided into two categories,
with 40 each. Category I (made of IPS e.max CAD) and Category II (made of CEREC blocs C PC). The specimens (3 mm
thickness, n=10) were cut, sintered, polished, glazed and cleaned before immersed in artificial saliva and simulated gastric
acid solution. Vickers micro hardness, surface roughness and surface morphology evaluations were taken before (baseline)
and after immersion.
Results: Paired t-test showed significant an increase of surface roughness for IPS e. max (glazed and without glazed) after
immersion in simulated gastric acid while there was significant decrease in surface roughness for CEREC blocs C PC (glazed
and without glazed) in the same acid. P value was not significant change for all groups when immersed in artificial saliva.
The micro hardness decrease after immersion in both artificial saliva and gastric acid for all groups with no significant in
saliva but with significant in gastric acid and larger variability.