Four canines of eight 2-year-old dogs were extracted surgically, a mucoperiosteal flap being raised. A standardized pair of the post-extraction cavities were filled with three aspirin cones, the other pair being used as controls. The flaps were sutured with surgical gut. The dogs were killed at intervals of 2, 4, 6 and 8 weeks; bone blocks including the cavities were resected and decalcified for histologic examination; serial sections were stained with hematoxylin and eosin. Microscopic observation on 2 week samples showed an inflammatory response with granulation tissue in both experimental and control cavities with delayed bone apposition in cavities filled with aspirin cones. The 4, 6 and 8 week samples did not show any major difference between the experimental and control cavities. We observed a decrease in infiltrating of cells followed in both by a similarly increasing amount of fibrous tissue and bone remodeling. These results were due perhaps to the details of the experimental method as the suture allowed aspirin to stay in the cavities for only a short time (2-3 days), as occurs in clinical practice.
The aim of this study is to check the presence of zinc in salivary proteins and to define a relationship between zinc bonded with proteins and zinc free or bonded with low molecular weight substances.In order to avoid contamination of the examined material, we washed all glassware with HNO3 and then rinsed with bidistilled zinc-free water. Plastic equipment was used whenever possible. Previous atomic absorption spectrophotometric analysis of all the reagents and buffers demonstrated an insignificant content of zinc. We selected a group of 20 healthy male human subjects with good oral hygiene, aged from 20 to 40 years, previously clinically and radiologically checked. The sample collection took place in the morning: All subjects were instructed to refrain from breakfast, smoking, brushing of teeth; the samples were collected in sterile polystyrene test tubes fitted with plastic caps and immediately centrifuged at 20,000 x g for 30' at 00, thus separating pellet and supernatant, which were immediately frozen.When the required volume of saliva was reached, the samples were unfrozen and mixed obtaining two fractions: the 30 ml pellet and the 635 ml supernatant. Five hundred milliliters of supernatant were concentrated by ultrafiltration with Diaflo with PM 10 Arhicon membrane at 3 atm into 7 ml. We preferred to use the concentration by ultrafiltration to the lyophilization technique in order to avoid the increased danger of altering the proteins. From the ultrafiltrated 492 ml, 220 ml were again ultrafiltrated by using um 0.5 Amicon membrane in order to have the most exact evaluation for the zinc free or bonded with very low molecular weight substances. The quantitative analysis was made with an atomic absorption spectrophotometer Perkin Elmer 403 equipped with an airacetylene burner, and the zinc concentration was calculated by comparison with a standard zinc curve. We have also analyzed the specimens with two other techniques: mineralization at 2000 -3000 adding HNO3 plus H2SO4 and H202, and mineralization after lyophilization.We found no significant difference in the results obtained from the three different techniques. We found the following results: Zinc concentration in saliva pellet Concentration of zinc free or bonded with very low MW substances Concentration of zinc bonded with proteins with MW >~10,000 206 ppb (72.6%) 56 ppb (19.7%) 22 ppb ( 7.7%)We wish to point out the importance of the analysis of zinc concentration in the pellet, which has not been considered in other investigations.In order to study the distribution of zinc bonded with proteins in the various proteinic fractions, five milliliters (about 275 mg of proteins) of the material concentrated by ultrafiltration with PM 10 Amicon membrane were applied on a Sephadex G-150 column (3 x 100 cm), which was equilibrated with 0.10 M phosphate buffer (pH 6.8). The proteins were measured by two spectroscopic methods that reflect distinctive protein properties, absorbance at 215 nm and at 280 nm. Absorbance at 280 nm is determined principally by the amou...
Oxytalan fibres in hyperplastic gingival papillae from 12 young epileptics who had been treated with sodium diphenyl‐hydantoin were studied with modifications of Fullmer and Lillie's (1958) and Löe and Nuki's (1964) staining methods. These fibres were compared with the fibres in clinically normal gin‐givac and in tissue from fibrous epulides. Fibres reacting with peracetic acid‐aldehyde fuchsin (i.e. oxytalan fibres) were present throughout the connective tissue and were especially numerous near the surface epithelium and in areas of inflammatory infiltration. The oxytalan fibres were especially prominent along the junction with epithelium, between the rete pegs and in the deeper connective tissue near bone where they tended to be arranged in large parallel bundles. In cases of fibrous epulis, however, there were very few oxytalan fibres in the connective tissue adjacent to the surface epithelium. It is concluded that the connective tissue performs an important supportive function to the epithelium in gingival hyperplasia, and is of special importance in the genesis of gingival hyperplasia in patients under treatment with sodium diphenyl‐hydantoin.
Energy dispersive x‐ray spectrometry (EDAX system), with scanning electron microscopy was used to detect diffusion of Zn from a source in human dentin and the system was tested for sensitivity and reproducibility. Sections of human teeth in which a ZnO‐eugenol cement had been placed in a cavity in the dentin in vivo were prepared and x‐ray microanalytical measurements carried out. We found that values of counts for Zn, Ca and P in the same field were linear up to a total counting time of 60 sec. We further found that reproducibility of values between repeat examinations of the same specimens on different days was excellent. The concentration of Zn in the dentin decreased exponentially with distance from source within the distance tested. We conclude that the system can be used to detect trace concentrations of Zn, and that accordingly the diffusion behavior of a variety of ions in dentin could be monitored.
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