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T K Vaidyanathan

Publications and source records attributed to T K Vaidyanathan.

6 recordsLinked to original sources

Digital imaging techniques for dental alloy castability quantification.

In this study, mesh monitors cast from experimental compositions of a Ni-Cr-Be alloy are evaluated by the application of image analysis techniques. Castability values obtained by this method are then contrasted with those from three commonly employed manual counting procedures. While castability values obtained by all methods reflect the effect of compositional variations, a comparison of results with respect to evaluation method indicates that the image analysis technique consistently yields higher castability values, especially evident in the poorly casting groups. The apparent explanation for these observed differences is that with imaging, segments that are partially cast to varying degrees are not arbitrarily eliminated from the data, as is the usual practice in manual counting methods; therefore, castability values obtained by using the imaging technique will very closely reflect an actual alloy volume of each cast monitor.

Beryllium

Thermoanalytical characterization of visible light cure dental composites.

Selected commercial and experimental composites and resin systems have been evaluated by thermal analysis techniques of Differential Scanning Calorimetry, Thermogravimetric Analysis and Thermomechanical Analysis. Important thermal data such as heat of cure, coefficient of thermal expansion, dimensional changes over selected temperature ranges, filler weight percent, onset temperature of decomposition, etc. have been determined. Heat of cure, thermal expansion coefficient and dimensional changes appear to follow an inverse linear regression fit with filler fraction in the composite. Thermal expansion changes and exothermic reactions with temperature indicate secondary cure during postcure heating. The thermally-induced decomposition occurs in multiple stages indicating presence of different structural species in the resin matrix.

Bisphenol A-Glycidyl Methacrylate

In vitro deformation failure analysis of dental amalgams.

The in vitro deformation failure behavior of the conventional and the recent high copper dental amalgams is studied under different strain rates. The conventional silver-tin amalgams exhibited significant slow compressive flow at low strain rates, but failed catastrophically at the higher loading rates. On the other hand, amalgams containing highest copper contents showed no compressive flow and failed catastrophically at all the loading rates. The slow compressive flow in the conventional dental amalgams indicate that dislocations may play an important role in the deformation process of the amalgams at the lower strain rates.

Copper