A Comparison of Dimensional Accuracy of Addition Silicone of Different Consistencies with Two Different Spacer Designs - In-vitro Study.
INTRODUCTION
Dimensional accuracy of impression materials is crucial for the production of working casts in Fixed Prosthodontics. The accurate replication of tooth preparations and their arch position requires impression materials that exhibit limited distortion.


METHODS
This study was conducted to comparatively evaluate the dimensional accuracy of additional silicones by comparing two different techniques and spacer designs, by measuring the linear changes in interpreparation distance. The impressions were made from a stainless steel master die simulating a three unit bridge. A total 80 die stone (type IV, Ultrarock) models were obtained from the impressions made using two different parameters. The two different parameters are Multimix and Monophasic technique and different spacer designs.


RESULT
The interpreparation distance of the abutments in the casts was measured using a travelling microscope. Each sample was measured thrice and the mean value was calculated. The results obtained were statistically analysed and the values fall within the clinically acceptable range.


CONCLUSION
The most accurate combination is multimix technique with spacer design which uses less bulk of impression material.
Effect of Intermixing Brands on the Dimensional Accuracy of Master Cast using Putty-wash Impression Technique.
AIM
The aim of this study was to evaluate the effect of intermixing brands of addition silicone impression materials on the dimensional accuracy of stone models using two-step putty-wash technique.


MATERIALS AND METHODS
Two common brands of addition silicone impression material (Express and Aquasil) were used in this study. A total of 40 impressions of a stainless steel model simulating a three-unit bridge were made, 10 impressions for each group. Accuracy was assessed by measuring two dimensions (inter-abutment and intra-abutment) on stone models obtained from impressions of the stainless steel model. Each sample was measured thrice and the mean value was calculated. The data were analyzed using analysis of variance (ANOVA) and Scheffe's post hoc test.


RESULTS
The results indicated that each of the inter-abutment and intra-abutment dimensions of the stone models was significantly higher than those for the stainless steel model (p < 0.001). However, there was no statistically significant difference in each of the inter-abutment and intra-abutment dimensions of the stone models among the four tested groups (p < 0.05).


CONCLUSION
The results obtained were statistically analyzed and the values of the inter-abutment and intra-abutment dimensions were all within the clinically acceptable range.


CLINICAL SIGNIFICANCE
Intermixing brands of additional silicone impression materials evaluated in this study did not affect the dimensional accuracy of obtained stone casts. This will help to minimize the wastage of materials due to lack of either light or putty consistency of the same brand of additional silicone impression material.
The Cosmopolitan Imagination: The Renewal of Critical Social Theory
Gerard Delanty provides a comprehensive assessment of the idea of cosmopolitanism in social and political thought which links cosmopolitan theory with critical social theory. He argues that cosmopolitanism has a critical dimension which offers a solution to one of the weaknesses in the critical theory tradition: failure to respond to the challenges of globalization and intercultural communication. Critical cosmopolitanism, he proposes, is an approach that is not only relevant to social scientific analysis but also normatively grounded in a critical attitude. Delanty's argument for a critical, sociologically oriented cosmopolitanism aims to avoid, on the one hand, purely normative conceptions of cosmopolitanism and, on the other, approaches that reduce cosmopolitanism to the empirical expression of diversity. He attempts to take cosmopolitan theory beyond the largely Western context with which it has generally been associated, claiming that cosmopolitan analysis must now take into account non-Western expressions of cosmopolitanism.