Biomedical subjects
G Schmalz
Publications and source records attributed to G Schmalz.
[Streptococcus mutans: a review of the literature. II].
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[Streptococcus mutans: a review of the literature. I].
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[The effect of methyl-methacrylate monomer on L-cell metabolism].
The total serum protein synthesis, amino acid assimilation, rate of cell division, and DNA synthesis with various concentrations of methyl methacrylate monomer in medium was determined in a culture of L 929 fibroblasts of the mouse. DNA synthesis was inhibited after 12 hours of incubation. The normal course of cell division was completely supressed with a concentration of 3.2 . 10(-2) mol/l. A decrease in protein synthesis was observed after 24 hours of incubation. This decrease may be considered the result of DNA inhibition.
[Biological and physical studies on a new alloy for the demonstration of a new gamma 2-free amalgam].
Physical and biological characteristics as well as the clinical behavior of a new powdered alloy mixture (ISO 1559--1978) for the demonstration of a gamma 2-free amalgam were studied. The physical values surpassed the requirements of the Preliminary German Industrial Standards No. 13904. Compared with other gamma 2-free types of amalgam, the structure of the amalgam composed of the alloy under study contained no additional copper-containing phases which would negatively influence electrochemical events within the amalgam structure, except for the eta'-phase. Implantation tests with rabbits showed that the amalgam composed of the material under study reacted like material tested in earlier investigations which is already available.
[In vitro study on the toxicity of an odorless and tasteless zinc oxide-eugenol cement (Iso-Protect)].
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[Experiences with the prep-trainer].
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[Animal experimental tests of a new filling material (Isocap)].
An experimental investigation with animals (Rhesus monkeys) concerning pulp tolerance to two premeasured dosages of calcium hydroxide cement (Reocap and Reocap-E) as well as a pre-measured dosage of filling material (Isocap) in an injection capsule was carried out (78 class V cavities). As with the negative controls, a very slight reaction, or none at all, developed in response to the two calcium hydroxide cements and the new filling material, with and without application of capping material. When five other accidentally exposed pulpae were dissected, direct capping under the corresponding preconditions (punctate exposed pulpa, longer storage period for calcium hydroxide cement) showed the characteristic formation of reparative dentin.
[Comparison between 2 elution methods for biological testing of materials].
The possibility of separating the eluate and the actual biologic test for determining tissue tolerance was studied using two cements containing copper and two cements without copper. Both the materials and the two eluates obtained according to the different procedures were tested immediately. Distilled water was added to one sample of the material, and the mixture was placed in an autoclave for one hour. A second sample was leached in nutrient solution for 24 hours at 37 C. Uniform results were obtained with the copper-free material. Results with the material containing copper however varied; the results of the eluate obtained after one hour in the autoclave were different from the results obtained after 24 hours in the nutrient solution or after direct testing. The test results for the last two procedures were similar. Comparison of the two elution methods indicates that extraction in physiologic nutrient solution is better than the autoclave method using distilled water.
[The effect of various front tooth filling materials on the in vitro growth of Streptococcus mutans].
While silicate cement inhibits bacterial growth, resin materials promote it immediately after mixing. Toxic tissue reactions may be induced by bacterial plaque accumulation. Our testing method complements existing in-vitro tests for recording chemo-toxic activities.
[Antimicrobial properties of cements with and without copper content].
Copper-containing cements seem to inhibit bacterial growth better than copper-free materials. Twenty-four hours after insertion, a statistically significant difference is noted. The initial bactericidal effect of copper-free cements declines considerably as compared to copper-containing cements. The results obtained largely correspond to those given in the literature. The method used of including bacterial suspension in a liquid medium is suitable to establish dose-reaction curves for dental materials.
[The sensitivity of various in-vitro-test systems in biological testing of materials].
In the present paper the biological activity of methylmethacrylate Monomer and di-methylparatoluidin on stationary, cell-proliferating and bacterial cultures is examined. The equi-toxic concentrations were lower in cell culture systems than in stationary cell suspensions or bacterial cultures. Accordingly biological reaction appears to depend on the effective concentration of the toxic substance as well as on the specific sensitivity of the test system. There is no correlation between the sensitivity of cellular and of bacterial test systems.
[The effect of amyloglucosidase and glucoseoxydase containing toothpastes on plaque formation and gingivitis].
Earlier studies showed that an antibacterial lactoperoxydase system in the saliva is activated by the application of a hydrogen paroxide-generating combination of enzymes: amyloglucosidase and glucose oxydase. The object of the present study was to investigate the effect of these enzymes in a test and control group of 29 subjects. The results showed the plaque-inhibiting effect of the enzyme paste. An influence on the gingiva could not be demonstrated.
[Lymphocyte code for the diagnosis of bovine leukosis in herds under sanitation].
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A modification of the cell culture agar diffusion test using fluoresceindiacetate staining.
In order to reduce the uncertainties involved in the morphologic evaluation of the cell culture agar diffusion test, the originally recommended neutral red stain was replaced by fluoresceindiacetate (FDA). This stain proved to be nontoxic in the concentrations used in this study (0.002%). Toxicity tests with phenol, formalin, and methylmethacrylate monomer revealed results corresponding to literature evaluations by other methods. Since FDA makes cell metabolism visible and easily accessible to automated evaluation techniques, it presents certain advantages over the morphologic evaluation using the neutral red stain.
In-vivo evaluation of a feldspathic ceramic system: 2-year results.
OBJECTIVES: The aim of this clinical study was to evaluate feldspathic ceramic inlays by clinical criteria and quantitative margin analysis, and to compare clinical performance with the quantitative margin analysis results. METHODS: Fifty fibre-reinforced feldspathic ceramic inlays were placed in box-shaped, Class II preparations with all margins located in enamel. A low-viscosity type dual-curing resin luting material was used for luting. The inlays were evaluated clinically according to modified US Public Health Service criteria after 2 days, 1 year, and 2 years. In addition, quantitative margin analysis was performed under a scanning electron microscope using an image analysing system. RESULTS: Clinically the inlays performed very well after 2 years, showing no changes in colour, no recurrent caries and no marginal discolouration. Because of the wear of the composite resin luting material, margins were perceptible with an explorer in 54% of the cases after 2 years. Quantitative margin analysis showed significantly (P < or = 0.05) more marginal gaps at the composite/ceramic interface compared with the enamel/composite interface at each evaluation. There was a significant increase in marginal gaps at both interfaces during the first year, whereas marginal gaps at the composite/ceramic interface did not increase significantly during the second year. Quantitative margin analysis showed that both time and interface had a significant influence on marginal gaps. CONCLUSION: Quantitative margin analysis should be included in clinical long-term trials on this type of restoration to recognize possible deficiencies in ceramic, composite resin luting material, and the luting interfaces.
Ehlers-Danlos syndrome type VIII with severe periodontitis and apical root resorption after orthodontic treatment.
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Influence of amalgam, alloy, and mercury on the in vitro growth of Streptococcus mutans: I. Biological test system.
A procedure is presented for the in vitro growth of Streptococcus mutans in a dextrose-beef extract medium. Growth was estimated spectrophotometrically. The amount of amalgam, alloy, or mercury that was added to the sealed test tube influenced the rate and extent of growth.