Document Detail


Influence of prolonged setting time on permanent deformation of elastomeric impression materials.
MedLine Citation:
PMID:  20416412     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
STATEMENT OF PROBLEM: Upon removal, tear forces occur in various areas of an impression. As a result, thin sulcus details may be permanently deformed, affecting the impression's accuracy. PURPOSE: The purpose of this study was to investigate the effect of the chemistry and prolonged setting time on the permanent deformation of light-body impression materials after stretching. MATERIAL AND METHODS: A dumbbell-shaped mold (2 mm x 4 mm x 75 mm) was used to prepare specimens (n=20) of 6 different impression materials (Affinis Light Body, Aquasil Ultra XLV, Express 2 Light Body Flow Quick, Flexitime Correct Flow, P2 Polyether Light, and Impregum Garant L DuoSoft). After water storage (35 degrees C), either for the manufacturer's suggested setting time or for 5 minutes, specimens were stretched by 80% using a universal testing machine at a crosshead speed of 200 mm/min. The permanent deformation (Deltal (%)) was determined after 2 hours of storage in ambient conditions. A 2-way ANOVA followed by a Games-Howell test was used to analyze the influence of material and storage time (alpha=.05). RESULTS: Polyether materials showed a significantly higher permanent deformation (Deltal>4% to 5%) than vinyl polysiloxane materials (P<.05). Extending the manufacturer's suggested setting time resulted in clinically relevant improvements in elastic recovery for products with a polyether backbone only. CONCLUSIONS: Increasing the setting time might be necessary for impression materials with a polyether backbone to improve elastic recovery.
Authors:
Markus Balkenhol; Sylvia Haunschild; Christina Erbe; Bernd Wöstmann
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  The Journal of prosthetic dentistry     Volume:  103     ISSN:  1097-6841     ISO Abbreviation:  J Prosthet Dent     Publication Date:  2010 May 
Date Detail:
Created Date:  2010-04-26     Completed Date:  2010-07-15     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  0376364     Medline TA:  J Prosthet Dent     Country:  United States    
Other Details:
Languages:  eng     Pagination:  288-94     Citation Subset:  D; IM    
Affiliation:
Department of Prosthodontics, Justus Liebig University, Giessen, Germany. markus.balkenhol@dentist.med.uni-giessen.de <markus.balkenhol@dentist.med.uni-giessen.de>
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Dental Impression Materials / chemistry*
Dental Stress Analysis / instrumentation
Elastic Modulus
Elasticity
Elastomers / chemistry*
Humans
Materials Testing
Polyvinyls / chemistry
Resins, Synthetic / chemistry
Siloxanes / chemistry
Stress, Mechanical
Surface Properties
Temperature
Time Factors
Water / chemistry
Chemical
Reg. No./Substance:
0/Dental Impression Materials; 0/Elastomers; 0/Impregum; 0/Polyvinyls; 0/Resins, Synthetic; 0/SENN polyvinylsiloxane-polyether hybrid; 0/Siloxanes; 0/aquasil; 0/vinyl polysiloxane; 7732-18-5/Water

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  An in vitro evaluation of zirconia surface roughness caused by different scaling methods.
Next Document:  A descriptive study of the radiographic density of implant restorative cements.