Dimensional analysis of alginate molds after storage
DOI:
https://doi.org/10.7308/aodontol/2016.52.2.08Keywords:
Alginates, Dimensional measurement accuracyAbstract
Aim: The objective of this study was to evaluate the dimensional stability of the molds of two different alginates (Cavex Color Change® and Hydrogum®5), at different intervals, kept in environments, as recommended by manufacturers, using two different devices (D1 and D2, figures 1 and 2, respectively).
Methods: After the manipulation and complete cured of alginates, measurements were made directly in the alginate molds, at times T0, T1, T2, T3, T4, and T5 (immediately, 30 min, 2 hours, 24 hours, 48 hours, and 120 hours, respectively), to calculate the percentage of dimensional change of the molds in each device. Data were analyzed by the Two-Way ANOVA and Tukey post-hoc test, with a 5% significance level.
Results: Statistical analysis showed differences between times (F = 29.956, p<0.001), but no differences were observed between the alginates (F = 3.155; p = 0.076) for device 1. For device 2, statistically differences were found for both time (F = 21.495; p<0.001) and alginates (F = 5.595; p = 0.015).
Conclusions: The tested alginates can only be safely stored for up to two hours after their cure.
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References
Shen Chiayi. Materiais de moldagem. In: Phillips Materiais Dentários. Rio de Janeiro: Elsevier; 2005. p. 224-32.
Craig R G, Powers, J. Impression materials. In: Dental Materials. Mostby; 2000. p.138- 78.
Imbery TA, Nehring J, Janus C, Moon PC. Accuracy and dimensional stability of extended – pour and conventional alginate impression materials. J Am Dent Assoc. 2010; 141: 32-9.
Combe EC, Grant AA. The selection and properties of materials for dental practice. Brit Dent J. 1973; 197-200.
Buchan S, Peggie RW. Role of ingredients in alginate impression Compounds. J Dent Res. 1966; 45: 1120-9.
Fellows CM, Thomas GA. Determination of bond and unbond water in dental alginate irreversible hydrocolloid by nuclear magnetic resonance spectroscopy. Dent Mat. 2009; 25: 486-93.
Todd JA, Oesterle LJ, Newman SM, Shellhart WC. Dimensional changes of extended-pour alginate impression materials. Am J Orthod Dentofacial Orthop. 2013 Apr;143 Suppl 4:S55-63.
Fano V, Gennari PU, Ortalli I. Dimensional stability of silicone-based impression materials. Dent Mater. 1992; 8:105-9.
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 (Tehran). 2014 Nov;11(6):655-64.
Kulkarni MM, Thombare RU. Dimensional Changes of Alginate Dental Impression Materials-An Invitro Study. J Clin Diagn Res. 2015 Aug;9(8):ZC98-ZC102.
Erbe C, Ruf S, Wöstmann B, Balkenhol M. Dimensional stability of contemporary irre- versible hydrocolloids: humidor versus wet tissue storage. J Prosthet Dent. 2012 Aug;108(2):114-22.
Shen C. Impression Materials. In: Anusa- vice KJ. Phillips’ science of dental materials. 11th ed. Philadelphia: Saunders; 2003. p. 206- 43.
Nassar U, Aziz T, Flores-Mir C. Dimensional stability of irreversible hydrocolloid impression materials as a function of pouring time: a systematic review. J Prosthet Dent. 2011 Aug;106(2):126-33.