International conference on multidisciplinary science

THE EFFECT OF ADDING SOME CHEMICAL MATERIALS ON THE WATER POWDER RATIO OF DENTAL STONE RUNNING TITLE: THE EFFECT OF CHEMICAL MATERIALS ON THE DENTAL STONE

Amer A Taqa

Prof. Dr. DBS. Dept. College of Dentistry, University of Mosul, IRAQ

Nada Z. Mohammed

Prof. Dr. DBS. Dept. College of Dentistry, University of Mosul, IRAQ

Tariq Y. K. Bash

Department of Prosthodontics, College of Dentistry, University of Mosul, IRAQ

##semicolon## water powder ratio, dental stone, plaster, Elite, Zeta

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सार

To determine the effect of some chemical materials on the water powder ratio of dental stone. Material and Methods: Three types of chemical materials (rosin, nigella stavia oil and sodium lauryl sulfate) were incorporated into three kinds  of type III dental stone (Zeta, Elite and Dental stone) at four concentrations (0.5%, 1%, 1.5% and 2%). The collected data of water powder ratio were subjected to the descriptive analysis (mean and stander deviation), student T test (to evaluate the difference between  standard  and  experimental  groups)  and  one-way  analysis  of variance  (ANOVA)  (to  show  if there  are  significant differences among experimental groups). Results: Revealed that the incorporation of these chemical materials into each type of dental stone resulted in changing their evaluated water powder ratio; this change varies with the type, concentration of the added chemical material and type of dental stone being used. Conclusion: The most pronounced effect of the chemical additives that used in this study on the water powder ratio of the experimental dental stones was achieved with the addition of sodium lauryl sulfate.

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