Aim: To compare the retentive ability and deformation of Acetal resin with Cobalt-Chromium clasps via Insertion Removal apparatus after subjecting them to stimulate clinical use. Materials and Methods:Materials used for this study are commercially available Cobalt-Chromium alloy namely Wironit, Bego, Germany and Acetal resin namely Biodentaplast, Bredent, Germany. The test samples were divided into two major groups based on the type of materials used in the study. Each major group is further subdivided into two sub groups based on the retentive undercut depths used to engage the clasps. So a total of 20 specimens were prepared, comprising of 5 specimens in each sub group. Then the specimens were tested for retention force and deformation. Results:The results of this study indicate that acetal resin clasps are resistant to deformation and may offer a clinical advantage over the conventional metal clasps. The retentive force of acetal resin clasps did not decrease over the cycling periods. This would be attributed to the resilient nature of acetal resin. Under the conditions of the present study cobalt chromium clasps lost retentive force within 730 cycles of placement and removal and continued to lose retentive force during the remaining test period. Conclusion:This invitro study demonstrated that retentive force of cobalt chromium clasp is superior to that of Acetal resin for removable partial dentures. As acetal resin clasps exhibits greater flexibility and long term retentive resiliency, it can be used for removable partial dentures where aesthetics or periodontal health is a primary concern.A. Meenakshi et al.,

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A detailed theoretical analysis has been carried out to study efficient heating of one‐dimensional (1‐D) composite dielectric food slabs due to microwaves. Current study involves processing of beef with oil layers with/without ceramic support for various cases, such as the support and/or oil layer is directly exposed to microwaves (case 1), the beef layer is directly exposed to microwaves (case 2) and oil‐beef layers and the ceramic supports are exposed to microwaves at both the sides (case 3). A preliminary analysis on microwave heating has been carried out for beef‐oil composite without any support and the maxima in average power corresponding to resonances occur at various sample thicknesses for all cases. The detailed spatial distribution for various cases illustrates that for small oil thicknesses, heating rate is less and greater heating rate would correspond to larger oil thicknesses specially for case 1. The similar analysis has been extended for all cases with oil layer directly attached with ceramic supports (Al2O3 and SiC). The detailed analysis on spatial distribution of temperature and power during one side incidence illustrate that the greater thermal runaway occurs for case 2 with Al2O3 support corresponding to smaller oil thickness whereas SiC support may cause thermal runaway for larger oil thicknesses. For distributed microwave incidences (case 3), it is observed that Al2O3 support may cause thermal runaway whereas SiC support may reduce the thermal runaway, based on suitable distribution of microwaves at both sides. © 2006 American Institute of Chemical Engineers AIChE J, 2006

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Three dry adult human skulls, two with bilateral and one with unilateral duplication of the optic canal were found. Their gross morphologic features were studied. Optic canals were separated by a septum of variable thickness dividing the posterior part of the canal into a large canal in the usual position and a smaller one inferior to it. The skull with unilateral duplication of the right side had a bony bar forming the carotico-clinoid canal. One of the skulls was disarticulated and its sphenoid had bilaterally duplicated optic canals divided by thin septa, both having a slit. Conventional radiography and CT scans for the optic canal were performed on two of these skulls but not on the disarticulated bone, and the imaging representations of these features were correlated with the anatomic findings on the dry skull.