THE IMPACT OF AQUATIC ENAMEL PEELS AND CORN STARCH POWDERS ON THE MECHANICAL CHARACTERS OF ACRYLIC RESIN DENTURE BASE MATERIAL

To estimate the effects of different polysaccharide powders (corn starch and chitin) on the hardness and impact strength of heat-cured acrylic resin.Materials and methods: in this study, 28 samples were made from heat-cured acrylic resin, 14 of them have a disc shape with a dimension of 12mm and 2mm in thickness for hardness test (7 for chitin and 7 for corn starch group), while 14 of them were with a rectangular shape with a dimension of (65 mm, 10 mm, 2.5 mm) for impact strength test (7 for chitin and 7 for corn starch group).1% of manually prepared chitin powder and 1% of corn starch powder were included to acrylic resin, then, they were flasked, packed, cured and finally finished and polished.14 of samples were subjected to hardness test and the other 14 samples were subjected to impact strength test by using different types of devices.Results: The outcomes of the current study showed that 1% of manually prepared of chitin powder had the lowest mean value for both hardness and impact strength tests, while 1% of corn starch powder had the highest mean value for both hardness and impact strength tests.Conclusion: Manually prepared chitin powder had a negative impact on the mechanical characters of polymethylmethacrylate powder in comparison with corn starch powder which achieved the best findings.