Evaluation of Some Properties of Iraqi Plaster by Using Some Additives and Microwave Drying Technique
DOI:
https://doi.org/10.32828/mdj.v12i1.827Keywords:
Iraqi plaster, Microwave drying, open air drying, Gum ArabicAbstract
Abstract
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).
References
- Craig RG, O'Brien WJ, and Power JM. Dental Materials Properties and Manipulation. 6 ed., Mosby Co.; 1996. P. 242-265.
- Craig RG. Restorative Dental Materials. 10th ed. Mosby Co.; 1997. chap. 11, 12. p. l27-136, 500-540.
- Sanad ME, Combe EC, and Grant AA. The use of additives to improve the mechanical properties of gypsum products. J Dent Res. 1982; 61: P. 808-810.
- Schwedhelm ER and Lepe X (1997). Fracture strength of type IV and type V die stone as a function of time. J Prosthet Dent. 1997; 78(6):554- 559.
- Fan PL, Power JM, and Reid BC. Surface mechanical properties of stone, resin, metal and dies. J Amer Dent Assoc. 1981; 103(3):408-411.
- Aiach D, Malone WF, and Sandrick J. Dimensional accuracy of epoxy resin and their compatibility with impression material. J Prosthet Dent. 1984; 52(4):500-504.
- Zakaria MR, Johnston MW, Reisbick MH, and Campagni WV. The effects of a liquid dispersing agent and microcrystalline additives on the physical properties of type IV gypsum. J Prosthet Dent. 1988; 60(5):630-637.
- Craig RG and Power JM. Restorative Dental Materials. 11th ed. Mosby Co.; 2002. P. 635-670,392-404.
- Toreskog S, Phillips RW, and Schnell RJ. (1966): Properties of die materials a comparative study. J Prosthet Dent. 1996; 16(5): 119-131.
- Sanad ME, Combe EC, and Grant AA. Hardening of model and die materials by an epoxy resin. J Dent. 1980; 8(2): 158-162.
- Kotsiomiti E,Pissiotis A, kalotannides A and Diakoyianni MI.Effects of the addition of ammonium salts on improved dental stones surface hardness. Hellenic Dent J. 1995; 5: 45-50.
- Singh R,Ringh K, Agrawal KK, A comparative study of physical properties of gypsums manufactured in India .J Indian prosthethhodont Soc. 2013 Dec. 13 (4) ; 531-5.
- Mohammed NZ. The effect of adding some chemical materials on the physical and chemical properties of dental stone.[Master's thesis]. University of Mosul ; 2005. 85p.
- Luebke RJ and Chan KC. Effect of microwave oven drying on surface hardness of dental gypsum products. J Prosthet Dent. 1985; 54(3):431-435.
- Tuncer N, Tutekcioglu HB, and Calikkocaoglu S. Investigation on the compressive strength of several gypsum products dried by microwave oven with different programs. J Prosthet Dent. 1993; 69(3):333- 339.
- Nishii M. Studies on the curing of denture base resins with microwave irradiation with particular reference to heat curing resins. J Osaka Dent Unive. 1986; 2: 23-40.
- Kimura H, Teraoka F, Ohvishi H, Saito T, and Yato M. Application of microwave for dental techniques Part I Dough forming and curing of acrylic resin. J Osaka Dent Sch. 1983; 23: 42-49.
- Curry AA Rached RN, and Ganzarolli SM (2001): Microwave cured acrylic resins and silicon gypsum molding technique. J of Oral Rehabil. 2001; 28; 433-438.
- Truong UT and Thomasz FG. Comparison of denture acrylic resins cured by boiling water and microwave energy. Aust Dent J. 1988; 33:201-204.
- Sanders JL, Levin B, and Reitz PV. Comparison of the adaptation of acrylic resin cured by microwave energy and conventional water bath. Quintessence Int. 1991; 22(3): 181-186.
- Kazanoglu Aand Moon PC. Microwave heating of die stone. J Dent Res.1982; 61:304.
- Al- Hadad NS, Al-Mandilawi LR, and Al-Doori DI. Compressive strength of several gypsum products dried by microwave oven with different programs. Iraqi Dent J. 2001; 28:219-231.
- Mohammed SA. The effect of processing variable on the surface hardness, flow and setting time of gypsum materials. [Master's thesis].University of Alabama; 1983. 63p.
- Mohammed A.A. Evaluation of some properties of gypsum products of acrylic resin by the use of some additives and microwave technique. [Master thesis].University of Mosul; 2006. p.50.
- American dental Association specification (ADA). (Guide to dental materials and devices .7th ed. Chicago ADA. 1975; pp 203-208.
- Salem SA, Al- Hadithi KK, and Al-Shakhily GA. The effect of disinfectant solutions On some properties of dental stone cast. Iraqi Dent J. 1997; 19: 51-70.
- Aljubouri ZA and Alrawas AM. The petrography and Menirology of Technical plaster and local Juss . Iraqi Journal for earth Science. 2006; 34.
- Al- Sadi S, Combe EC, and Cheng YS. Properties of gypsum with addition of gum Arabic and calcium hydroxide. J Prosthet Dent. 1996; 76(5):530-534.
- Thornton J. A brief history and review of the early practice and materials of gap- filling in the west. J Amer Inst Conser. 1998; 37 (1): 3- 22.
- Seniour SS (1992): A study on dental hemihydrates produced from Egyptian gypsum raw materials. Doctor of philosophy (PhD) Thesis, University of Cairo.
- Abdelaziz KM, Attia A, and Combe EC. Evaluation of disinfectant casts poured in gypsum with gum Arabic and calcium hydroxide additives. J Prosthet Dent. 2004; 92(1): 27-34.
- Hersek N, Canay S, Akca K, and Ciftci Y. Tensile strength of type IV dental stones dried in a microwave oven. J Prosthet Dent. 2002; 87(5):499-502.
- Combe EC. Notes on dental materials .4 ed. Huntsmen offset printing PT Ltd; 1991. p. 97 -140,241-253.
- Ridge MJ and Boell GR. Effects of some additives on the water requirement of calcined gypsum. J Appl. Chem. 1992; 12:521-526.
- Scrabeck JG, Fames WB, and Hicks MJ. Spatulation methods and porosities in investments and impression materials. J Prosthet Dent. 1986; 55(3): 332-335.
- O'Brien WJ. Dental materials and their selection. 2nd ed. Quintessence book; 2002. p. 56-60.
- Aniisavice KJ. Phillips science of dental materials. 10 ed. WB Saunder Com;1996. P. 185-208.
- Prombonas A and Vlissidis D. Compressive strength and setting temperatures of mixes with various proportion of plaster to stone. J Prosthet Dent. 1994; 72(1): 95-100.
- Luebke RJ and Schneider RL. Microwave oven drying of artificial stone. J Prosthet Dent. 1985; 53(2): 261-265.
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This work is licensed under a Creative Commons Attribution 4.0 International License.
