Journal of Iranian Dental Association
J Iran Dent Assoc
Medical Sciences
http://jida.ir
23
journal23
2383-3041
10.52547/jida
en
jalali
1399
7
1
gregorian
2020
10
1
32
3
online
1
fulltext
en
Effects of Water/Powder Ratio of Irreversible Hydrocolloid
on Dimensional Stability of Impressions
Prosthodontics
Prosthodontics
Original
Original
<div style="text-align: justify;"><strong>Background and Aim: </strong>Water/powder ratio is effective on some properties of irreversible hydrocolloid impression materials. This study aimed to determine the ef-fects of water/powder ratio of irreversible hydrocolloid impression materials on di-mensional stability of impressions.<br>
<strong>Materials and Methods: </strong>In this in vitro experimental study, a metal model with two abutments as anchoring support for a three-unit dental bridge was used. Sixty alginate impressions were made with different water/powder ratios (control group and test group with 50% extra water). The impressions were made by acrylic trays. Alginate impressions were poured with dental stone after 15, 60 and 240 min of removal from the model. The diagonals and heights of the small and large dies as well as the outer space between the two dies were measured trice using a digital caliper with 0.01 mm accuracy, and the mean values were reported. The obtained dimensions were com-pared with each other and with the model. Data were analyzed by one-way ANOVA, one-sample t-test, and independent samples t-test (α=0.05).<br>
<strong>Results: </strong>In the majority of dimensions in both the control and test groups, there was a significant difference in comparison with the metal model. The mean dimensions of casts did not show any significant difference between the two groups after 240 min (P>0.1).<br>
<strong>Conclusion: </strong>Increasing the water added to alginate powder by 50% affected the di-mensional stability of the resulted casts. The time interval before pouring the cast had a significant effect on dimensional accuracy of the casts.</div>
Dental Impression Materials, Colloids, Alginates
43
49
http://jida.ir/browse.php?a_code=A-10-1-955&slc_lang=en&sid=1
Ehsan
Ghasemi
2300319475328460022809
2300319475328460022809
No
Assistant Professor, Dental Materials Research Center and Department of Prosthodontics, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran
Behnaz
Ebadian
ebadian@dnt.mui.ac.ir
2300319475328460022810
2300319475328460022810
Yes
Professor, Dental Implant Research Center and Department of Prosthodontics, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran
Alireza
Asadi
2300319475328460022811
2300319475328460022811
No
Dentist, Private Office, Isfahan, Iran
Nafiseh
Ghasemi
2300319475328460022812
2300319475328460022812
No
Dentist, Private Office, Isfahan, Iran