Elastomeric Impression Materials: A Comparison of Accuracy of Multiple Pours

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.

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Dimensional Stability of Elastomeric Impression Material After Disinfection Via Immersion and Microwave Irradiation

The Open Dentistry Journal ◽

10.2174/1874210602115010658 ◽

2021 ◽

Vol 15 (1) ◽

pp. 658-663

Author(s):

Noorhayati R. Mohd ◽

Ros A. Omar ◽

Enas A. Etajuri

Keyword(s):

Microwave Irradiation ◽

Dimensional Stability ◽

Control Group ◽

Clinical Settings ◽

Image Analyzer ◽

Impression Material ◽

Average Percentage ◽

Dimensional Changes ◽

Impression Materials ◽

Post Hoc

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.

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The Influence of Tray Space and Repeat Pours on the Accuracy of Monophasic Polyvinylsiloxane Impression

The Journal of Contemporary Dental Practice ◽

10.5005/jp-journals-10024-1236 ◽

2012 ◽

Vol 13 (6) ◽

pp. 824-829 ◽

Cited By ~ 4

Author(s):

Anand Rajapur ◽

Santosh Dixit ◽

Chetan Hoshing ◽

Sonal Raikar

Keyword(s):

General Practice ◽

Clinical Significance ◽

Dimensional Stability ◽

Dimensional Accuracy ◽

Time Intervals ◽

Impression Material ◽

Dimensional Changes ◽

Abutment Teeth ◽

Spacer Thickness

ABSTRACT Aim While literature demonstrates that the optimum accuracy is obtained with the custom trays, the use of stock trays for elastomeric impressions appears to be popular in general practice. The aim of the study was to evaluate the effect of thickness of impression material on the dimensional accuracy of impressions made from monophasic polyvinylsiloxane impression material. This study also studies the dimensional stability of the impressions poured at different time intervals. Materials and methods A metal model simulating two abutment teeth was fabricated along with reference lines inscribed on them. Custom impression trays were fabricated with spacer thickness of 2, 4 and 6 mm. impressions were made using monophasic polyvinyl siloxane impression material. The impressions were poured and stone models were obtained. The dimensional accuracy of the impressions were determined indirectly by measuring the dimensional changes of the recovered stone models. The dimensional stability was also evaluated by pouring the impressions at time intervals of 1 hour, 24 hours and 7 days. The obtained data was statistically analyzed. Results The results of the study indicated that the impressions made from 2 and 4 mm tray space produced more accurate stone models when compared to 6 mm tray space. There was no significant deviation in the mesiodistal and buccolingual dimensions when impressions were made using impression trays with 2, 4 and 6 mm tray spacers. There was a significant decrease in interabutment distance (p = 0.001) and height of the abutment (p = 0.024) when impressions were made using impression trays with a tray space of 6 mm. There were no significant differences found among the stone models obtained from 1 hour, 24 hours and 1 week pour times. Conclusion The mesiodistal and buccolingual dimensions of the abutments were not affected by the variations in thickness of impression material. There was a decrease in the height of the abutment which was clinically not significant. As the thickness of the impression material increased, the interabutment space decreased, which is a factor of concern when impressions are made for fixed partial dentures. Clinical significance When monophasic polyvinylsiloxane is used as the impression material, stock trays can be used for making impressions for individual castings. How to cite this article Rajapur A, Dixit S, Hoshing C, Raikar S. The Influence of Tray Space and Repeat Pours on the Accuracy of Monophasic Polyvinylsiloxane Impression. J Contemp Dent Pract 2012;13(6):824-829.

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The Effects of Chemical Disinfection on Dimensional Stability among Different Type of Impression Addition Silicon Materials

International Journal of Innovative Research in Medical Science ◽

10.23958/ijirms/vol05-i12/1029 ◽

2020 ◽

Vol 5 (12) ◽

pp. 645-649

Author(s):

Salah A. Yousief ◽

Khames T. Alzahrani ◽

Suha M. Alhuwairini ◽

Fai Y. Alharbi ◽

Dalal A. Eissa ◽

...

Keyword(s):

Standard Deviation ◽

Epoxy Resin ◽

Dimensional Stability ◽

Control Group ◽

P Value ◽

Impression Material ◽

Dimensional Changes ◽

The Mean ◽

Master Model ◽

The Cross

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.

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Dimensional Stability and Accuracy of Silicone – Based Impression Materials Using Different Impression Techniques – A Literature Review

PRILOZI ◽

10.1515/prilozi-2017-0031 ◽

2017 ◽

Vol 38 (2) ◽

pp. 131-138 ◽

Cited By ~ 1

Author(s):

Borjan Naumovski ◽

Biljana Kapushevska

Keyword(s):

Literature Review ◽

Dimensional Stability ◽

Storage Time ◽

Elastic Recovery ◽

Impression Material ◽

Impression Technique ◽

Impression Materials ◽

Scientific Papers ◽

Materials Used ◽

Stability And Accuracy

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.

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A Comparative Study on Accuracy and Reproducibility of Alginate and Addition Reaction Silicone as an Impression Materials.

Update Dental College Journal ◽

10.3329/updcj.v3i2.17996 ◽

2014 ◽

Vol 3 (2) ◽

pp. 28-33

Author(s):

Shakila Fatema ◽

Sheikh Md Shahriar Quader ◽

Mohammad Shamsuzzaman ◽

Mirza Md Arifur Rahman ◽

Nasima Khan

Keyword(s):

Addition Reaction ◽

In Vitro Study ◽

Dimensional Accuracy ◽

Horizontal Line ◽

Impression Material ◽

Dimensional Changes ◽

Impression Materials ◽

Study Results ◽

Surface Detail

Background: To achieve accuracy and exact reproduction of prosthesis, choosing a perfect impression material is essential. Especially to make the prosthesis as accurately as possible, impression material should possess some essential properties, like; minimum dimensional changes, good flow ability and easy removal. Purpose: The aim of this study was to evaluate the accuracy and surface detail reproduction of Alginate and Addition Reaction Silicone as an impression materials. Method: This is an experimental in vitro study. In this study Impression by Alginate and Addition Reaction Silicone were made using a round stainless steel test block with three horizontal lines and two vertical lines. The horizontal lines were used for evaluating the surface detail reproduction, and vertical lines were provided for the dimensional accuracy. For dimensional accuracy the length of the middle horizontal line in between vertical lines and the distance between the top and bottom horizontal line was measured using travelling microscope. And for surface detail reproduction three horizontal line of one segment were observed under stereomicroscope. Result: According to study results Addition Reaction Silicone is better than Alginate regarding quality of impression. Conclusion: In comparison to Alginate, Addition Reaction Silicone might have better performance about accuracy and surface detail reproduction. DOI: http://dx.doi.org/10.3329/updcj.v3i2.17996 Update Dent. Coll. j: 2013; 3 (2): 28-33

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“EVALUATION OF SURFACE DETAIL REPRODUCTION OF BD IMPRESS AND NEXUS MEDODENT THERMOPLASTIC IMPRESSION MATERIALS” - AN IN VITRO COMPARATIVE STUDY

10.36106/ijsr/1532645 ◽

2021 ◽

pp. 28-30

Author(s):

Ajay Balaji ◽

Naveen .B.H ◽

Kalavthi. S.D ◽

arun Thomas Philip

Keyword(s):

Comparative Study ◽

Dimensional Stability ◽

P Value ◽

Thermoplastic Material ◽

Impression Material ◽

Good Surface ◽

Impression Materials ◽

Surface Detail ◽

Essential Prerequisite

Impression making is the primary step in the process of fabrication of prosthetic restoration. Dimensional stability, Surface detail reproduction, and compatibility with gypsum products is an essential prerequisite for a successful restoration. Clinically, the accuracy of impressions depends on two major aspects: 1) Ability to ow and adapt intimately to the relevant surfaces while making the impression, and 2) the wetting of the polymerized impression material by the gypsum. The purpose of this study is to evaluate and compare the surface detail reproduction of BD Impress and Nexus Medodent impression material. The results showed signicant difference in surface detail between the two thermoplastic impression materials with p-value <0.05. It was observed that comparison of mean scores obtained by BD Impress and Nexus Medodent impression material are 2.7556 and 2.2222 respectively. The materials with minimum mean score value is considered as the material with good surface detail reproduction. Thus one can conclude that Nexus Medodent thermoplastic material has the good surface detail reproduction compared to BD Impress thermoplastic material.

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Volumetric Change as a Parameter for the Accuracy of Impression Materials

Journal of Biomimetics Biomaterials and Biomedical Engineering ◽

10.4028/www.scientific.net/jbbbe.36.17 ◽

2018 ◽

Vol 36 ◽

pp. 17-23

Author(s):

Mihaela Păpușa Vasiliu ◽

Liliana Sachelarie ◽

Carmen Stadoleanu ◽

Cătălina Gîrbea ◽

Agripina Zaharia

Keyword(s):

Mechanical Strength ◽

Dimensional Stability ◽

Setting Time ◽

Reproductive Capacity ◽

Volumetric Change ◽

Impression Material ◽

Dental Prostheses ◽

Impression Materials ◽

Study Results

In this paper we studied the behavior of some impression materials such as alginate, condensation and addition silicones, considering the following parameters: the reproductive capacity of morphological details - dimensional stability - the ability to reproduce with accuracy the ratio between morphological elements. The essential conditions that an impression material should fulfill are plasticity, fidelity, flexibility, good mechanical strength, dimensional stability, suitable setting time and compatibility with materials from which the models are manufactured.The study results indicated that condensation silicones present the highest volumetric changes, their contraction being the result of the evaporation of volatile byproducts.The dimensional stability of fingerprint materials is one of the variables that contribute to the accuracy or inaccuracy of dental prostheses, other factors being represented by the changes occurring during the preparation of the fingerprint material as well as the fingerprinting techniques.

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Comparison of double-phase impression technique in 1 step and 2 steps by evaluating dimensional stability and accuracy of condensation silicones

Macedonian Pharmaceutical Bulletin ◽

10.33320/maced.pharm.bull.2017.63.01.006 ◽

2018 ◽

Vol 63 (01) ◽

pp. 55-61

Author(s):

Borjan Naumovski ◽

Jadranka Bundevska ◽

Biljana Kapusevska

Keyword(s):

Dimensional Stability ◽

Impression Material ◽

Impression Technique ◽

Impression Materials ◽

Double Phase ◽

Dental Impression ◽

Master Model ◽

Stability And Accuracy ◽

Plaster Model ◽

Selection Of

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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Dietary and behavioral inferences from dental pathology and non-masticatory wear on dentitions from a British medieval town

10.1101/222091 ◽

2017 ◽

Author(s):

Ian Towle ◽

Carole Davenport ◽

Joel D. Irish ◽

Isabelle De Groote

Keyword(s):

Tooth Loss ◽

Cultural Practices ◽

Permanent Teeth ◽

Central Incisor ◽

Maxillary Central Incisor ◽

Anterior Teeth ◽

Dental Pathology ◽

Carious Lesions ◽

Antemortem Tooth Loss ◽

Time Periods

AbstractDental pathology and wear data can provide valuable insights into diet, cultural practices, and the health of populations. In this study, various dental pathologies and types of wear were recorded for 41 individuals (914 permanent teeth), excavated from the medieval cemetery of St. Owens Church in Southgate Street, Gloucester. Teeth were studied macroscopically with a 10x hand lens to confirm the presence of specific pathologies. Relatively high rates of antemortem chipping on the anterior teeth, and the presence of maxillary central incisor notches, suggested that the Gloucester population commonly used their teeth for non-masticatory activities. Abscessing and antemortem tooth loss fell within previously reported ranges for British medieval sites (2.6% and 6% respectively). However, the sample exhibits extremely high levels of carious lesions and calculus. Nearly 24% of teeth have at least one carious lesion, and the presence of calculus was recorded in 74% of teeth within the sample. Overall caries frequency is similar to sites from later time periods. This frequency may reflect Gloucester’s location as a large port town. Remains from the same area, but the earlier Roman period, also shows high rates of both caries and calculus, suggesting a continuation of consuming certain cariogenic foods is likely.

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EVALUATION OF LINEAR DIMENSIONAL STABILITY OF BD IMPRESS AND NEXUS MEDODENT THERMOPLASTIC IMPRESSION MATERIALS – AN IN VITRO COMPARATIVE STUDY

10.36106/ijsr/6529543 ◽

2021 ◽

pp. 22-25

Author(s):

Arun Thomas Philip ◽

Kalavthi. S.D ◽

Naveen. B.H ◽

Ajay Balaji

Keyword(s):

Comparative Study ◽

Clinical Application ◽

Dimensional Stability ◽

Impression Material ◽

Parallel Lines ◽

Impression Materials

Aim: To evaluate and compare the linear dimensional stability of two commercially available BD IMPRESS and NEXUS MEDODENT thermoplastic impression materials. A total of 90 samples in which 45 s Methodology: amples of BD Impress and Nexus medodent impession materials were used for evaluation of linear dimensional stability of these newly introduced thermoplastic impression materials. The samples were rst checked under toolmaker microscope for reproduction of three parallel lines x,y,z. The measurements were made on the samples at 0 (within 24 hours), 7th and 14th day respectively to assess the linear dimensional stability. According to the study conducted and results obtained, it Result: was concluded that NEXUS MEDODENT was superior in linear dimensional stability on comparison with BD IMPRESS impression material Conclusion: On comparison with BD impress, nexus medodent impression material was superior in terms of linear dimensional stability. There is a need for further studies to know about other properties of these thermoplastic impression materials to enhance knowledge and for clinical application as indicated by manufacturers.

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