ABSTRACT
Background: Flow characteristics of vinyl polysiloxane (VPS) impression materials are important determinants in the selection of impression materials for the fabrication of accurate indirect restorations. Aims: The purpose of this study was to determine the flow of three commercially available VPS impression materials at different time intervals using a shark fin device (3M ESPE, Seefeld, Germany). Study Setting and Design: This in?vitro study was carried out at the prosthodontics department of a dental institution. Methods and Material: The height of the shark fin produced by each impression material determined the rate of flow. Statistical Analysis: The data were analysed using one?way analysis of variance (ANOVA) and post?hoc Tukey’s test (p?0.05). Results: Shark fin height of group A VPS impression material was significantly higher at 30 and 120 seconds compared to group B and group C VPS impression materials. Shark fin height produced by group B VPS impression materials at 60 and 90 seconds was significantly higher than the group C VPS impression material but non?significant compared to group A. At 120 seconds, there was no significant difference in the shark fin heights of all the tested materials. Conclusion: All the materials exhibited adequate flow characteristics within clinically acceptable limits
ABSTRACT
Titanium and its alloys are being extensively researched and are applied relatively in different fields of dentistry since 1970s. Every property of this metal has proven to be useful in allied branches of dentistry like casting of removable partial denture frameworks, endosseous implants, in surgical reconstruction and orthodontics. Its inherent advantages like high strength, ductility, formability and weldability, low modulus of elasticity, ease of formation of oxidized surface layer, ability to retain mechanical integrity after autoclave and relatively low toxicity has led to extensive application of titanium and its alloys. The success of the treatment modality relies anyways on the knowledge of the properties required to employ them at the right situation. This article provides an insight into the properties of titanium and its alloys employed as a biomaterial for variety of purposes in dentistry with its definitive pros and cons.