Dimensional change over time of extended-storage alginate impression materials
- 1 November 2010
- journal article
- research article
- Published by The Angle Orthodontist (EH Angle Education & Research Foundation) in Angle Orthodontist
- Vol. 80 (6), 1110-1115
- https://doi.org/10.2319/031510-150.1
Abstract
Objectives: To evaluate the dimensional change over time of two extended-storage alginate impression materials. Methods: Impressions were made of stainless steel dies in accordance with ADA Specification No. 18 using three alginates: two extended-storage alginates and one conventional alginate. The impressions were stored for 30 minutes, 48 hours, or 100 hours (n = 10 impressions/material/storage time). Following the respective storage times, dimensional change was measured by comparing the length of the middle horizontal line in the impression with the same line on the die and computing percent difference. Results: Significant differences in dimensional change were noted between materials across time (P < .05). All materials exhibited shrinkage after 30 minutes, with the conventional alginate continuing to shrink over time and the extended-storage alginates expanding with increased storage time. The conventional alginate was most accurate after 30 minutes. In contrast, one extended-storage alginate demonstrated minimal dimensional change at all storage times, and another was most accurate after 100-hour storage. Conclusions: Evidence suggests that delayed pouring with dental gypsum should not adversely affect dimensional accuracy of the generated casts with both extended-storage alginates. However, only one of the extended-storage materials appears suitable for both short-term and extended-storage applications.Keywords
This publication has 13 references indexed in Scilit:
- Determination of bound and unbound water in dental alginate irreversible hydrocolloid by nuclear magnetic resonance spectroscopyDental Materials, 2009
- The Relationship between Digital Model Accuracy and Time-Dependent Deformation of Alginate ImpressionsAngle Orthodontist, 2009
- Dimensional changes of alginate dental impression materialsJournal of Materials Science: Materials in Medicine, 2006
- Impact of water quality on setting of irreversible hydrocolloid impression materialsThe Journal of Prosthetic Dentistry, 2006
- Current Products and Practices OrthoCAD™: digital models for a digital eraJournal of Orthodontics, 2004
- Factors affecting the accuracy of elastometric impression materialsJournal of Dentistry, 2004
- Comparison of measurements made on digital and plaster modelsAmerican Journal of Orthodontics and Dentofacial Orthopedics, 2003
- Dimensional Accuracy of Three Different Alginate Impression MaterialsJournal of Prosthodontics: Implant, Esthetic, and Reconstructive Dentistry, 1995
- Alginate dental impression materials: Chemistry, structure, and propertiesJournal of Biomedical Materials Research, 1986
- Syneresis in alginate impression materialsBritish Dental Journal, 1975