Dental and Medical Problems
2018, vol. 55, nr 1, January-March, p. 43–48
doi: 10.17219/dmp/82179
Publication type: original article
Language: English
License: Creative Commons Attribution 3.0 Unported (CC BY 3.0)
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Effect of water quantity and quality on the properties of alginate impression materials
Wpływ jakości i ilości wody na właściwości alginatowych materiałów wyciskowych
1 Spofa Dental Kerr Company, Jičin, Czech Republik
2 Department of Dental Prosthetics, Wroclaw Medical University, Poland
3 Department of Experimental Dentistry, Wroclaw Medical University, Poland
Abstract
Background. Alginates are impression materials commonly used in prosthodontics and orthodontics. However, all these materials have some disadvantages, such as limited elasticity, tearing resistance and low dimensional stability.
Objectives. The aim of this research was to investigate the effect of various water quantities and qualities on changes in the properties of alginates.
Material and Methods. Two alginates, Neocolloid and Tulip, were mixed with different volumes of water, water with calcium ions, or sparkling water with CO2. The dimensions, setting times, and hardness of the specimens were measured and Young’s modulus was calculated. The significance of the difference between the mean values of different groups and the control group was assessed by Student’s t-test or the Mann-Whitney U test.
Results. The dimensional stability changes of both alginate impression materials were statistically dependent on the quantity of water used for mixing. Sample storage over 24 h of samples prepared with +15% water led to 5.00% shrinkage for Neocolloid and 4.41% for Tulip. The setting times of Neocolloid and Tulip were significantly prolonged when the alginates were prepared with +15% water; the addition of calcium ions shortened the setting times of both alginates. Specimens mixed with the water containing Ca2+ ions were characterized by greater hardness and Young’s modulus values when compared to the alginate mixed with distilled water.
Conclusion. For mixing alginates, it is necessary to use the manufacturers’ recommended mixing ratios between powder and water. To obtain the right setting time, hardness and elasticity, the application of distilled or demineralized water is advised.
Key words
hardness, dental impression materials, irreversible hydrocolloids, storage conditions, dimensional changes
Słowa kluczowe
twardość, dentystyczne materiały wyciskowe, nieodwracalne hydrokoloidy, warunki przechowywania, zmiany wymiarów
References (20)
- King S, See H, Thomas G, Swain M. Determining the complex modulus of alginate irreversible hydrocolloid dental material. Dent Mater. 2008;24:1545–1548.
- Fellows CM, Thomas GA. Determination of bound and unbound water in dental alginate irreversible hydrocolloid by nuclear magnetic resonance spectroscopy. Dent Mater. 2009;25:486–493.
- Ercoli C, Abrahamsen TC. A simple method for making accurate duplicate casts. J Prosthet Dent. 1996;76:457.
- Brown D. Factors affecting the dimensional stability of elastic impression materials. J Dent. 1973;1:265–274.
- Sedda M, Casarotto A, Raustia A, Borracchini A. Effect of storage time on the accuracy of casts made from different irreversible hydrocolloids. J Contemp Dent Pract. 2008;9:59–66.
- Walker MP, Burckhard J, Mitts DA, Williams KB. Dimensional change over time of extended-storage alginate impression materials. Angle Orthod. 2010;80:1110–1115.
- Nassar U, Hussein B, Oko A, Carey JP, Flores-Mir C. Dimensional accuracy of 2 irreversible hydrocolloid alternative impression materials with immediate and delayed pouring. J Can Dent Assoc. 2012;78:c2.
- Nallamuthu NA, Braden M, Patel MP. Some aspects of the formulation of alginate dental impression materials-setting characteristics and mechanical properties. Dent Mater. 2012;28:756–762.
- Rohanian A, Ommati Shabestari G, Zeighami S, Samadi MJ, Shamshiri AR. Effect of storage time of extended-pour and conventional alginate impressions on dimensional accuracy of casts. J Dent (Teheran). 2014;11:655–664.
- Frank RP, Thielke SM, Johnson GH. The influence of tray type and other variables on the palatal depth of casts made from irreversible hydrocolloid impressions. J Prosthet Dent. 2002;87:15–22.
- Kulkarni MM, Thombare RU. Dimensional changes of alginate dental impression materials – An in vitro study. J Clin Diagn Res. 2015;9:ZC98–ZC102.
- Guiraldo RD, Moreti AF, Martinelli J, et al. Influence of alginate impression materials and storage time on surface detail reproduction and dimensional accuracy of stone models. Acta Odontol Latinoam. 2015;28:156–161.
- Dreesen K, Kellens A, Wevers M, Thilakarathne PJ, Willems G. The influence of mixing methods and disinfectant on the physical properties of alginate impression materials. Eur J Orthod. 2013;35:381–387.
- Farzin M, Panahandeh H. Effect of pouring time and storage temperature on dimensional stability of casts made from irreversible hydrocolloid. J Dent (Tehran). 2010;7:179–184.
- Wanis TM, Combe EC, Grant AA. Measurement of the viscosity of irreversible hydrocolloids. J Oral Rehabil. 1993;20:379–384.
- Powers JM, Sakaguchi RL. Impression materials. In: Restorative Dental Materials. 12th ed. St. Louis: Mosby; 2006;272–279.
- Gent AN. Indentation hardness and Young’s modulus. Transactions of the Institute of Rubber Industry. 1958;34:47–57.
- GC Corp (2008). Dental alginate impression material composition. US20080057465A1.
- GC Corp (2003). Dental alginate impression material composition. US patent 6,559,200 B1.
- Buchan S, Peggie RW. Role of ingredients in alginate impression compounds. J Dent Res. 1966;45:231–236.