The use of vinyl polysiloxanes and quick setting epoxies in paleontology

1989 ◽  
Vol 63 (2) ◽  
pp. 256-256 ◽  
Author(s):  
Patrick Leiggi
Keyword(s):  
Fast Method ◽  
Impression Material ◽  
Impression Materials ◽  
Dental Impression

Quick setting dental impression materials are nothing new in the paleontology laboratory. In a paleontological note published in the Journal of Paleontology on “The Use of Dental Impression Material For Molding Macrofossils” (Quilty & Williams, 1975), the products Xantopren and Optosil were introduced as a simple and fast method of obtaining precision molds in 1-3 minutes. Since the mid-1970's these products have been replaced by vinyl polysiloxanes.

A Replica Method for the Study of Marine Biofilms

1995 ◽  
Vol 75 (3) ◽  
pp. 759-762 ◽  
Author(s):  
S. J. Marrs ◽  
J. C. Thomason ◽  
M. J. Cowling ◽  
T. Hodgkiess
Keyword(s):  
Materials Science ◽  
Plant Morphology ◽  
Replica Method ◽  
Impression Material ◽  
Large Size ◽  
Impression Materials ◽  
Marine Biofilms ◽  
Dental Impression ◽  
Non Destructive ◽  
Standard Techniques

A replica method involving the use of a polyvinylsiloxane impression material with a resin cast, particularly suitable in the study of marine biofilms, is described. The technique has advantages over other methods in that it is quick, non-toxic, non-destructive and inexpensive. Replicas of critical-point dried eggcases of the dogfishScyliorhinus canicula(L.) (Elasmobranchii: Squaliformes) showed the replica to be true down to the size of bacteria. It was also possible to replicate larger areas such as patches of living barnacles on an intertidal rock.The study of marine biofilms often involves the use of destructive techniques such as conventional scanning electron microscopy (SEM), histology andin vacuospectroscopic methods (Baier & Meyer, 1986), so a single surface may not be examined repeatedly. Alternatively, the surface of interest may not be amenable to examination by standard techniques due to, for example, large size or incompatibility of the material of interest. In materials science the use of replica techniques to overcome such problems have been common (Goodhew, 1973), though techniques commonly involve the use of solvents (Loh, 1989) or silicone elastomers that may have a curing period of several hours (Gordon, 1984) and are consequently unsuitable for the study of biofilms. Scott (1982) reviewed the use of dental impression materials for field use in metallurgy and in recent years, dental impression materials have been used in the study of plant morphology (Green & Linstead, 1990). In this paper we consider the use of a hydrophilic polyvinylsiloxane impression material in the study of both microscopic and macroscopic marine biofilms.

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

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

scholarly journals Making of Alginate Dental Impression Material from Sargassum duplicatum

2020 ◽  
Vol 147 ◽  
pp. 03015
Author(s):  
Ellya Sinurat ◽  
Subaryono ◽  
Anantaria Okawati Rambe
Keyword(s):  
Calcium Sulfate ◽  
Room Temperature ◽  
Setting Time ◽  
Quality Parameters ◽  
Gel Strength ◽  
Impression Material ◽  
Final Setting Time ◽  
Impression Materials ◽  
Dental Impression ◽  
Time Variations

This study was aimed to prepare dental impression material from Sargassum duplicatum taken from Binuangeun, Banten. The setting time was tested according to ANSI/ADA Specification for Alginate Impression Materials 1983. After extraction, obtained the alginate powder then mixed its water/powder ratio from the combination of alginate composition and tested final setting time. Variations of the formulations used different calcium sulfate (0,1 g; 0,2 g; and 0,3 g). Product quality parameters are lumps, solubility, consistency, flow, tearing, setting time. The alginate yield obtained from Sargassum duplicatum by 31 % with characteristic gel strength by 816 (gr/cm2); viscosity 238 mPas (2%; room temperature). The highest ratio is the best ratio by adding calcium sulfate powder of 0.1 gram with a setting time of 3 minutes.

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