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Biomedical subjects

P Riethe

Publications and source records attributed to P Riethe.

At least 19 recordsLinked to original sources
PubMed1996

Antibacterial effects of amalgams on mutans streptococci in an in vitro biofilm test procedure.

Conflicting data continue to be presented in the literature regarding the antibacterial potential of various amalgam alloy compositions. The aim of the present study was to compare the antibacterial effects of 4 different amalgam samples on mutans streptococci using two in vitro test procedures. Glass and bovine enamel served as negative controls. The first test, one commonly used, consisted of immersing freshly prepared disks of the six materials in culture broth inoculated with mutans streptococci. Optical density measurements of the broth served to evaluate bacterial growth. This was followed by a biofilm technique which provided more intimate contact between the bacteria and specimen surfaces. With the exception of one high-copper lathe-cut amalgam, the first test revealed no antibacterial potential of the samples whereas the second test with the biofilm design elucidated significant differences in antibacterial potential between the amalgam alloy compositions and the controls. The biofilm technique, used in an in vitro test procedure, reflects the conditions of the oral environment more accurately than conventional test designs.

Animals↗
PubMed1996

Vital fluorescence to assess in vitro and in vivo the antibacterial effects of amalgams.

The aim of the present study was to establish an alternative methodology for testing the antibacterial effects of different amalgams. The vitality of mutans streptococci grown in vitro on various amalgam surfaces was monitored with a vital fluorescence staining technique using fluorescein diacetate and ethidium bromide. The in vivo effect of amalgam-non-gamma 2 fillings on the vitality of dental plaque was assessed with the same method and compared with samples originating from enamel. The median in vitro vitality of mutans streptococci was estimated as 70% on glass, 50% on Amalcapnon-gamma 2 and Sybraloy, 20% on Amalcap F and 10% on Neo-Silbrin. In vivo plaque vitality on enamel varied from 60 to 70%. In contrast, plaque sampled from non-gamma 2-amalgam surfaces revealed significant reductions in vitality with a minimum value of 25% of one day old supragingival plaque. The vital fluorescence technique was shown as an easy and quick method to assess the bactericidal effect against biofilm bacteria of dental materials in vitro as well as in vivo.

Anti-Bacterial Agents↗
PubMed1991

[Tooth protecting chewing gum tablets for lessening caries risk].

This study examines whether the regular use of sugar-free chewing gum can improve oral hygiene and therefore reduce the risk of caries. During a four-week test, twenty subjects chewed a piece of gum twice a day for thirty minutes after meals. At the start, after two weeks, and at the end of the test period, the plaque and gingiva indices were recorded and the buffer capacity and secretion rate of the saliva determined. At the end of the test, a substantial reduction in the plaque and gingiva indices, an increase in the secretion rate and an improvement in buffer capacity were found, in comparison with the start levels. The changes were statistically significant. Sugar-free chewing gum alone is no substitute for regular dental care, but its use can be recommended as a way of supplementing traditional methods of oral hygiene.

Adult↗
PubMed1989

[Clinical test of two toothpastes of different composition].

In two series of clinical tests, the effect of two toothpastes of differing formulation were examined in respect of their plaque removal efficiency and their influence on inflammatory reactions of the periodontal margin. The remarkable improvements in the oral health of a group of "non-dentists" compared to "dentists" are certainly attributable to personal motivation and instruction on oral hygiene with brush and toothpaste, but also to the formulation of the paste which may have influenced these results.

Clinical Trials as Topic↗