scholarly journals The effect of disinfectants on dimensional stability of addition and condensation silicone impressions

2014 ◽  
Vol 71 (3) ◽  
pp. 251-258 ◽  
Author(s):  
Tamara Sinobad ◽  
Kosovka Obradovic-Djuricic ◽  
Zoran Nikolic ◽  
Slobodan Dodic ◽  
Vojkan Lazic ◽  
...  

Background/Aim. Dimensional stability and accuracy of an impression after chemical disinfection by immersion in disinfectants are crucial for the accuracy of final prosthetic restorations. The aim of this study was to assess the deformation of addition and condensation silicone impressions after disinfection in antimicrobial solutions. Methods. A total of 120 impressions were made on the model of the upper arch representing three full metal-ceramic crown preparations. Four impression materials were used: two condensation silicones (Oranwash L - Zhermack and Xantopren L Blue - Heraeus Kulzer) and two addition silicones (Elite H-D + regular body - Zhermack and Flexitime correct flow - Heraeus Kulzer). After removal from the model the impressions were immediately immersed in appropriate disinfectant (gluta-raldehyde, benzalkonium chloride - Sterigum and 5.25% NaOCl) for a period of 10 min. The control group consisted of samples that were not treated with disinfectant solution. Consecutive measurements of identical impressions were realized with a Canon G9 (12 megapixels, 2 fps, 6x/24x), and automated with a computer Asus Lamborghini VX-2R Intel C2D 2.4 GHz, by using Remote Capture software package, so that time-depending series of images of the same impression were obtained. Results. The dimensional changes of all the samples were significant both as a function of time and the applied disinfectant. The results show significant differences of the obtained dimensional changes between the group of condensation silicones and the group of addition silicones for the same time, and the same applied disinfectant (p = 0.026, F = 3.95). Conclusion. The greatest dimensional changes of addition and condensation silicone impressions appear in the first hour after their separation from the model.

2021 ◽  
Vol 15 (1) ◽  
pp. 658-663
Author(s):  
Noorhayati R. Mohd ◽  
Ros A. Omar ◽  
Enas A. Etajuri

Aims: This study aimed to evaluate and compare the dimensional stability of two elastomeric impression materials, namely polyvinyl siloxane (PVS) and vinyl siloxanether (VSE), subjected to chemical immersion and microwave irradiation for disinfection. Materials and Methods: Sixty discs of PVS and VSE impression materials each were prepared using a stainless-steel test die and ring in accordance with ANSI/ADA Specification No. 19. Twenty discs of each impression material were disinfected by chemical immersion for 10 min; another 20 discs were subjected to dry microwave irradiation for 3 min. The other 20 discs served as a control group. Dimensional stability measurements were then performed using an image analyzer at 20× magnification. The data were analyzed by one-way analysis of variance (α=0.05) and Bonferroni (post hoc) test for multiple comparisons to detect significant differences between the groups. Results: When subjected to microwave irradiation, both PVS and VSE showed dimensional changes, but the changes were within the limit of 1.5% set by ANSI/ADA (P<0.00). VSE showed markedly better results than PVS for both disinfection methods. The immersion disinfection method resulted in a higher average percentage of linear dimensional changes than both the microwave irradiation and the control for VSE and PVS impression materials. Conclusion: VSE exhibited excellent dimensional stability than PVS under both chemical immersion and microwave irradiation. Microwave irradiation using conventional microwave ovens can be used in clinical settings as an alternative to other disinfection techniques because the dimensional changes of the elastomeric impression materials subjected to microwave irradiation have been observed to be within the clinically acceptable limit set by the ANSI/ADA standard.


2004 ◽  
Vol 12 (3) ◽  
pp. 244-249 ◽  
Author(s):  
Sávio Marcelo Leite Moreira da Silva ◽  
Milton Carlos Gonçalves Salvador

The purpose of this study was to evaluate the dimensional stability of heavy and light bodied condensation silicones after immersion in disinfectant solution for 10 or 20 minutes. The impression materials were Optosil Comfort and Xantopren VL Plus and the disinfectant solutions were 1% sodium hypochlorite and 2% glutaraldehyde. Impressions were made on a perforated stainless steel tray, according to the American Dental Association specification No. 19, adding up to a total of 50 samples. The double mixing method (one time, two viscosities) was used. Impressions were removed from the roulette block after 7 minutes to ensure complete curing and then immersed in the solutions. Impressions not submitted to treatment composed the control group. After these steps, the impressions were removed from the solution, rinsed in running water and air-dried. Three-dimensional measurements were calculated using an optic microscope graduated at 0.001 mm. The two-way ANOVA indicated no differences (p>0.05) for any combination between variables. The results showed that the solution studied can be safely used to disinfect condensation silicone in clinical prosthodontic procedures.


2011 ◽  
Vol 12 (4) ◽  
pp. 272-278 ◽  
Author(s):  
Dheeraj Kumar ◽  
Anand U Madihalli ◽  
K Rajeev Kumar Reddy ◽  
Namrataa Rastogi ◽  
NT Pradeep

ABSTRACT Aim The aim of the present study is to compare the various elastomeric impression materials in terms of accuracy and dimensional stability, with respect to obtaining multiple casts from a single elastomeric impression at various times of pours. Materials and methods Three master dies were prepared for the impression making, two of these were made of brass containing a central hole with undercuts. The third die simulated a conventionally prepared typodont maxillary central incisor. Three elastomeric impression materials were chosen for the study. Each impression was poured at various time periods. Casts thus obtained were evaluated under a traveling microscope to evaluate various dimensional changes. Results Addition silicones provided dies which were shorter in height and bigger in diameter. Polyethers provided dies which were shorter in both height and diameter. Condensation silicones showed insignificant changes from the master die at the immediate pour but deteriorated rapidly after that in subsequent pours. Conclusion None of the impression material showed a consistent behavior up to the fourth pour. They occasionally showed deviation from the pattern, but all these values were statistically insignificant. Polyethers showed lesser ability than both the addition silicones as well as the condensation silicones to recover from induced deformation. Clinical significance Addition silicones as well as the condensation silicones have better ability to recover from induced deformation when compared to polyether. How to cite this article Kumar D, Madihalli AU, Reddy KRK, Rastogi N, Pradeep NT. Elastomeric Impression Materials: A Comparison of Accuracy of Multiple Pours. J Contemp Dent Pract 2011;12(4):272-278.


Author(s):  
Salah A. Yousief ◽  
Khames T. Alzahrani ◽  
Suha M. Alhuwairini ◽  
Fai Y. Alharbi ◽  
Dalal A. Eissa ◽  
...  

Introduction: Saliva and blood contaminated impressions are often a source of cross contamination between the clinic and dental laboratory. Explicit communication and observance of an infection control protocol for handling of dental impressions must exist among the office staff as well as between office and dental laboratories. Though disinfection of impression is routinely followed, autoclaving elastomeric impression is an effective method of sterilization them. Objectives: The purpose of this study was to evaluate dimensional stability and detail reproduction of a new addition silicon impression material after disinfection. Methods: In this study, a total of twenty impressions for the master model using heat resistant plastic stock trays. The twenty impressions were divided into two groups according to disinfection technique: (Table 2) Group 1: (n=10) Control group, untreated impressions. (C.G) Group 2: (n=10) Impressions were chemically disinfected. (D.G). after all impressions treatment, they were poured with extra hard stone (type IV) to get stone casts. Dimensional accuracy and detail reproduction of the impression material were evaluated indirectly through the recovered improved stone casts from impressions of the master model using the travelling microscope. Results: Cross arch distance (A): Epoxy resin master model cross arch distance measurement (A) was (41.36 mm). 1.1 Measurements of the cross-arch distance of stone casts Control group (C.G): The mean and standard deviation values of distance (A) in stone models obtained from C.G. were 41.553 ± 0.170 mm. Disinfection group (D.G): The mean and standard deviation values of distance (A) in stone models obtained from D.G were 41.368 ± 0.083 mm. ANOVA test showed that there was a statistically difference shrinkage between the groups (P-value = 0.006). 1.2 Measurement of the dimensional changes in the cross-arch distance of the different groups. The mean and standard deviation values of cross arch distance changes in stone models of C.G. were 0.191 ± 0.170 mm. while dimensional changes in stone models obtained from D.G. were 0.006 ± 0.082 mm. Conclusion: The purpose of this study was to evaluate dimensional stability and detail reproduction of a new addition silicon impression material after disinfection. In this study an epoxy resin master model was duplicated from a modified dentate mandibular model. Within the limitations of this study, it could be concluded that Chemical disinfectant of polyvinyl siloxane impression material can be successfully used in making fixed partial dentures.


PRILOZI ◽  
2017 ◽  
Vol 38 (2) ◽  
pp. 131-138 ◽  
Author(s):  
Borjan Naumovski ◽  
Biljana Kapushevska

Abstract A quality-made dental impression is a prerequisite for successful fixed-prosthodontic fabrication and is directly dependent on the dimensional stability, accuracy and flexibility of the elastomeric impression materials, as well as on the appropriately used impression techniques. The purpose of this paper is to provide a literature review of relevant scientific papers which discuss the use of various silicone impression materials, different impression techniques and to evaluate their impact on the dimensional stability and accuracy of the obtained impressions. Scientific papers and studies were selected according to the materials used, the sample size, impression technique, storage time, type of measurements and use of spacer for the period between 2002 and 2016. In the reviewed literature several factors that influence the dimensional stability and accuracy of silicone impression molds, including the choice of the type of viscosity, impression material thickness, impression technique, retention of the impression material on the tray, storage time before the casting, number of castings, hydrophilicity of the material, release of byproducts, contraction after polymerization, thermal contraction and incomplete elastic recovery were presented. The literature review confirmed the lack of standardization of methodologies applied in the research and their great diversity. All findings point to the superiority of the addition silicone compared to the condensation silicone.


2018 ◽  
Vol 21 (1) ◽  
pp. 37 ◽  
Author(s):  
Rafael Da Rocha Santos Penfold ◽  
William Cunha Brandt ◽  
Milton Edson Miranda ◽  
Rafael Pino Vitti

<p><strong>Objective:</strong> The aim of this study was to evaluate dimensional stability and detail reproduction in alginate molds stored at different times and temperatures. <strong>Material and </strong><strong>Methods:</strong> Three different commercially available alginates (Cavex Color Change, Jeltrate Plus and Hydrogum 5) were tested at four different times (0 - control, 1, 3 and 5 days) and two temperatures (25ºC and 37ºC) (n=5). The alginates were handled following the manufacturer's instructions. The impression procedures occurred in an environment with controlled room temperature (25ºC) and relative humidity (50±5%). A metallic model (ISO 1563:1990) was used to perform the impressions. The tray containing alginate remained on the metallic model under constant pressure (2 kgf) until the alginate gelation process. The molds were stored (different times and temperatures) and analyzed in stereomicroscope at 30x magnification and 0.5 μm accuracy (Olympus Measuring Microscope STM). The molds and the metallic model measurements were compared, and the data were statistically analyzed by Kolmogorov-Smirnov and three-way ANOVA tests, and the means were compared by Tukey test (5%). <strong>Results:</strong> The results showed no double interactions (p&gt;0.05) and the different alginates presented statistically similar values of dimensional stability (p=0.102). However, 25ºC (temperature) and control group (time) showed the highest values of dimensional stability (p&lt;0.05). Jeltrate Plus was the only material that presented inaccuracy in details reproduction. <strong>Conclusion</strong>: It is recommended that, for tested alginates, the stone casts should be poured immediately, even though the molds are dimensionally stable up to 5 days when stored at 25ºC.</p><p><strong> </strong></p><p><strong>Keywords</strong></p><p>Dental impression materials; Dimensional measurement accuracy; Shrinkage.<strong></strong></p>


2017 ◽  
Vol 5 (1) ◽  
pp. 59-70
Author(s):  
Wira Putri Winata ◽  
Kuswardani Susari Putri ◽  
Febrian Febrian

The impression materials that most commonly used in dentistry was alginate. Factors that must be considered was the controlled of infection transmission from alginate, it was important to do disinfection using a disinfectant solution. Alginate had imbibition properties, so that disinfection by spraying technique allowed the expansion of alginate affecting the dimensional stability of impressions. The purpose of this research was to determine the difference between the dimensional stability of alginate impression were sprayed with a solution of sodium hypochlorite 0,5% and Dettol® 5%.  The method used was an experimental laboratory with post test only control group design. 27 samples were divided into 3 groups: spraying with 0.5% sodium hypochlorite solution, spraying with 5% Dettol® solution, and spraying with aquades as a controlled. Alginate impressions were sprayed with 0,5% sodium hypochlorite solution, Dettol® 5%, and aquades then filled with gypsum, and then measured dimensional stability by using micrometer screw. Data were analyzed with the Kruskal-Wallis test.  The results showed that differences between the dimensional stability of alginate impressions were sprayed with a solution of sodium hypochlorite 0.5% and 5% Dettol® was not significant (p> 0,05).  The conclusion of this research was there was no significant difference between the alginate impressions were sprayed with a solution of sodium hypochlorite 0,5% and Dettol® 5% to dimensional stability. Keywords : dimensional stability, alginate, sprayed, sodium hypochlorite, Dettol®


2018 ◽  
Vol 63 (01) ◽  
pp. 55-61
Author(s):  
Borjan Naumovski ◽  
Jadranka Bundevska ◽  
Biljana Kapusevska

The diverse viscosities of silicone impression materials are suited for their use in various impression techniques, intended to improve the precision of the cast impression in the form of a plaster model. The purpose of this research is to determine the dimensional stability and accuracy of the double-phase impression technique in 1 step and 2 steps by using a condensation silicone impression material. This research was carried out by using a precise stainless-steel master model and an individual aluminum tray. Comparing the abutments of the master model and the abutments of the double-phase impression technique in 2 steps, showed that they are wider on average 81 µm, while the abutments from the double-phase impression technique in 1 step are on average 281 µm wider in diameter. After analyzing the results obtained in relation to the diameter of the abutments, it can be concluded that the double-phase impression technique in 2 steps is dimensionally more stable and accurate compared to the double-phase impression technique in 1 step. This study shows that dimensional stability and accuracy of impression materials also depend on the selection of appropriate impression technique and proper performance in order to obtain a high quality dental impression that will be the basis for an accurate fixed-prosthodontic fabrication. Keywords: silicone impression material, impression technique, fixed partial dentures, dimensional stability and accuracy


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