Evaluation of Some Properties of Iraqi Plaster by Using Some Additives and Microwave Drying Technique


  • Dr. Areej Shehab Ahmad




Iraqi plaster, Microwave drying, open air drying, Gum Arabic




Aims of this study:1- Evaluation of some properties of Iraqi plaster, compressive strength & surface roughness. 2- Improving the quality of Iraqi plaster by incorporation of some additives. 3- Studying the effect of microwave drying on the compressive strength & surface roughness of Iraqi plaster.

Methods: 56 samples of Iraqi plaster used in this study, divided into two main groups according to the main tests used, 28 samples for compressive strength & 28 samples for surface roughness.

          Samples of each test were divided into two groups (each group 14 samples). The first group was without additives, while the second includes the modified gypsum products (Iraqi plaster) with additives, (Gum Arabic 0.5%, calcium oxide 0.75%, and ferric oxide 0.2%).

          Samples of each subgroup are subdivided into two subgroups also according to the drying method of Iraqi plaster, Open air drying method & Microwave drying method (7 samples for each)

          Measuring of both tests was done in Technology University in Baghdad. Compressive strength measurement by using (unconfined compression machine), while, surface roughness of the samples was measured by Profilometer.

Results: The results showed that incorporation of additives to Iraqi plaster result in changing their evaluated properties & Comparing with open air drying method, microwave drying enhanced the properties tested in this study.

Conclusions: incorporation of additives to Iraqi plasters result in (Improvement of the compressive strength, reduction of the surface roughness and increase smoothness).





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How to Cite

Ahmad, D. A. S. (2019). Evaluation of Some Properties of Iraqi Plaster by Using Some Additives and Microwave Drying Technique. Mustansiria Dental Journal, 12(1), 39–52. https://doi.org/10.32828/mdj.v12i1.827



Prosthodontic Dentistry