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Notes: Purpose The hardness, porosity, and adaptation of removable partial dentures fabricated with one heat-polymerized denture base resin and two resins designed for microwave polymerization were evaluated.Materials and Methods Five prostheses were evaluated for each resin. Adaptation of the denture bases to the master cast was evaluated by spatial orientation and mean weight of residual impression material. The prostheses were then embedded in epoxy resin and sectioned for evaluation of resin hardness (Knoop hardness) and microporosity.Results There were no significant differences in the adaptation of the acrylic resin bases for Acron MC and Ch Lucitone. There was no significant difference in the mean Knoop hardness values for any of the resin bases near and away from the metal. None of the denture bases showed porosity greater than 100 μm.Conclusions Both resin bases formulated for microwave polymerization were effectively polymerized around metal frameworks without adverse effects on resin hardness or porosity. Justi Denture Base material had poorer base adaptation than the other two resins.

Notes: Purpose To determine if using CIE L*a*b* color measurements of white facial skin could be correlated to those of silicone shade samples that visually matched the skin. Secondly, to see if a correlation in color measurements could be achieved between the silicone shade samples and duplicated silicone samples made using a shade-guide color formula.Materials and Methods A color booth was designed according to ASTM specifications, and painted using a Munsell Value 8 gray. A Minolta colorimeter was used to make facial skin measurements on 15 white adults. The skin color was duplicated using custom-shaded silicone samples. A 7-step wedge silicone shade guide was then fabricated, representing the commonly encountered thicknesses when fabricating facial prostheses. The silicone samples were then measured with the Minolta colorimeter. The readings were compared with the previous L*a*b* readings from the corresponding patient's skin measurements, and the relative color difference was then calculated. Silicone samples were fabricated and analyzed for three of the patients to determine if duplication of the visually matched silicone specimen was possible using the silicone color formula, and if the duplicates were visually and colorimetrically equivalent to each other. The color difference Delta E and chromaticity was calculated, and the data were analyzed using a coefficient-of-variation formula expressed by percent. A Pearson Product Moment Correlation Coefficient was performed to determine if a correlation existed between the skin and the silicone samples at the p〈inlineGraphic alt="leqslant R: less-than-or-eq, slant" extraInfo="nonStandardEntity" href="urn:x-wiley:1059941X:JOPR237:les" location="les.gif"/〉 .05 level.Results The highest correlation was found in the b* dimension for silicone thicknesses of 1 to 4 mm. For silicone thicknesses of 6 to 10 mm, the highest correlation was found in the L* dimension. All three dimensions had positive correlations (R2 〉 0), but only the 1-mm and 4-mm b* readings were very strong. Patient and silicone L*a*b* measurement results showed very little change in the a* axis, while the L* and b* measurements showed more change in their numbers, with changes in depth for all patient silicone samples. Delta E numbers indicated the lowest Delta E at the 1-mm depth and the highest Delta E at the 10-mm depth. All duplicated samples matched their original silicone samples to a degree that visual evaluation could not distinguish any color differences. Using volumetric measurements, a shade guide was developed for all 15 patients.Conclusions There was good correlation between the patient's colorimeter measurements and the silicone samples, with the b* color dimension the most reproducible, followed by the L* and the a*. Silicone samples at 6, 8, and 10 mm matched the patient the best, and this study showed that silicone samples can be duplicated successfully if a good patient-silicone match is obtained. Rayon flocking fibers and liquid makeup are effective at matching facial prostheses and can be used to develop a simple shade guide for patient application.

Notes: Purpose This study evaluated the influence on dimensional accuracy of dental casts made with different types of trays and impression materials and poured at different and multiple times.Materials and Methods Two types of stock trays (plastic stock tray, perforated metal stock tray) and 4 types of custom tray materials (autopolymerizing acrylic resin, thermoplastic resin, and 2 types of light-polymerized acrylic resins) were used with 2 types of impression materials (addition polymerizing silicone and polyether), to make impressions of a metal master model. Each tray and impression material was used to make 5 impressions. Casts were made by multiple pourings at 30 minutes, 6 hours, 24 hours, and 30 days after impression making. Using a measuring microscope, 12 distances were calculated based on measurements of 8 reference points. The absolute value of the difference of each measurement was calculated, as was the corresponding measurement on the master model. A Bayesian model using a simple noninformative prior was used to analyze these data.Results Statistical differences within 6 μm were found only with thermoplastic resin tray material for addition silicone, and for thermoplastic resin tray material and 1 type of light-polymerized acrylic resin for polyether. Neither stock trays nor custom trays contributed to the differences in accuracy of the casts. All deviations in casts made with silicone impression material were within a clinically acceptable range. For the polyether, distortions occurred that were clinically unacceptable. Impressions made from polyether distorted over time. Silicone impression material has dimensional stability up to 30 days.Conclusion Accurate casts can be made with either stock trays or custom trays. An impression made from polyether should be poured only once and within 24 hours after impression making, because of the distortion of the material over time. Silicone impression material has better dimensional stability than polyether.

Notes: Serum biochemical profiles were compared in matched groups of premenopausal and postmenopausal women. Significantly higher concentrations of sodium, urea, calcium, albumin and alkaline phosphatase were found in the postmenopausal group. In the postmenopausal group, following treatment with sequential mestranol and norethisterone, significant reductions were recorded in the concentrations of sodium, urea, calcium, albumin, alkaline phosphatase and glucose and significant increases were recorded in the concentration of globulin and in body weight. The findings suggest that haemoconcentration may take place after the menopause and that this effect may be modified by hormone treatment. No adverse effect on liver function was noted following the hormone treatment.

Notes: The serum cholesterol and triglyceride concentrations of 84 postmenopausal women both before and after 2, 6 and 12 months therapy with various regimens of hormone therapy were measured. There was little alteration in mean serum cholesterol concentration with cyclical oestrogens but both sequential mestranol and norethisterone and sequential oestradiol valerate and norgestrel significantly reduced the mean serum cholesterol concentration to a level similar to that found in age-matched premenopausal women. There was a small and sometimes significant rise in serum triglyceride concentration with cyclical oestrogens. Sequential mestranol and norethisterone significantly elevated serum triglyceride levels, but sequential oestradiol valerate and norgestrel significantly depressed them. The results suggest that the progestogenic agent norgestrel has an important role to play in reducing both serum cholesterol and triglyceride levels, and that the sequential preparations, by virtue of their greater cholesterol lowering effect, should perhaps be preferred to cyclical oestrogens.

Notes: Abstract— The S-100 and 14-3-2 proteins, which are found only in nervous tissues, were measured in degenerating rabbit optic nerve at 0, 5 10, 20, 40, 60, 80, 100, 150 and 200 days after unilateral enucleation in order to obtain indications of the cellular localization of these proteins in the central nervous system. S-100 increased and 14-3-2 decreased (both approximately 70 per cent) in cut nerves by 200 days of degeneration. Changes in amounts of the proteins were related to cellular alterations which characterize the degenerative process, as demonstrated by electron microscopy. In uncut nerves (intact eye) from these experimental animals, S-100 increased and 14-3-2 decreased slightly at 5 days, after which time the levels of each returned to those approximating the content in corresponding nerves from unoperated control animals. No appreciable change in total soluble proteins was measured in degenerating or intact nerves. Since S-100 increased and 14-3-2 decreased in the degenerating optic nerve as it became relatively enriched in glial constituents but impoverished in axonal content, it is suggested that S-100 is primarily a glial protein and 14-3-2 predominantly a neuronal protein in the central nervous system.

Notes: Abstract An assay, based on complement fixation, was described for the S-100 protein, a protein characteristic of the nervous system. It was found to be distributed in all parts of the nervous system both peripherally and centrally. It was not possible to deduce from the distribution the localization in cell type, but in human brain the concentration in each of twenty-six areas was consistent from brain to brain.

Notes: Abstract— Several major brain-specific proteins have been detected in cephalopods by electrophoretic analysis of the soluble proteins extracted from the optic lobes and other organs of octopus and by 2-dimensional fractionation of the soluble proteins from optic lobes and hepatopancreases of octopus and squid. One of the brain-specific proteins from octopus, identified as 0-1, has been purified by chromatography on DEAE-cellulose, Sephadex G-150, and DEAE-Sephadex. The protein appears to be pure on the basis of several physicochemical criteria. Amino acid analysis indicates a high content of glutamic and aspartic acids or their amides (or both) and the lack of tryptophan. A molecular weight of 17,000 has been calculated from sodium dodecyl sulphate-gel electrophoresis, gel filtration and ultracentrifugation analysis. The preparation of a specific rabbit antiserum against 0-1 has allowed its determination by agar immunodiffusion and complement fixation techniques. With the latter procedure it has been shown that the protein is absent outside the nervous system, is present in a concentration of several mg/g wet weight in octopus brain and is widely distributed within the octopus central and peripheral nervous system and in several molluscan species. It is also present in optic lobes of octopus at early stages of development.