PubMed HealthSearch

PubMed · 9206421

Microbiological root canal sampling: diffusion of a technology.

Abstract

Diffusion is the process whereby a technology enters and becomes part of the health-care system. In the present study, diffusion of microbiological root canal sampling (MRS) among general dental practitioners within the city of Gothenburg was observed for 25 years, from the establishment of the Laboratory of Oral Microbiology in 1966. Laboratory records at 5-year intervals were analysed and adopters were categorized as 'occasional' (1-2 samples/year), 'selective' (3-10) or 'regular' (> 10) samples. The diagnostic accuracy was assessed by analysing the results of culturing 574 samples referred in 1986. The acceptance rate varied between 2.9 and 5.1% except in 1986 when 10.1% of the practitioners in the area referred root-canal samples. While a minority of the adopters used MRS as a standard procedure, the strategy appeared to be directed towards selection of special cases. The results of culturing revealed a predominance of facultatives. Although evidence of contamination was found, the practitioners frequently appeared to produce valid microbiological samples.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

A Molander, C Reit, G Dahlén. 1996. Microbiological root canal sampling: diffusion of a technology.. https://doi.org/10.1111/j.1365-2591.1996.tb01363.x

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Characterization of the proteolytic activity of starter cultures of Penicillium roqueforti for production of blue veined cheeses.

Thirty strains of Penicillium roqueforti used for the production of blue cheeses were examined for proteolytic activity by agar diffusion on casein agar, by the azocasein test and by capillary zone electrophoresis (CE). Distinct differences were seen between the strains by all three methods applied and the 30 strains could be subdivided in three groups being significantly different in their proteolytic activity as measured by the agar diffusion test. The quantitative differences seen in the agar diffusion test were confirmed by the azocasein test. However, a negative result on casein agar, i.e., no clearing of the agar was observed for one strain while it showed low proteolytic activity in the azocasein test. CE proved to be a valuable method for revealing qualitative differences between strains of P. roqueforti in the breakdown of casein. Three strongly proteolytic strains broke down the specific casein fractions differently: one strain broke down betaA1-casein faster than betaA2-casein, the second preferred alpha s1-casein while the last strain broke down the casein fractions at equal rates. For a strain with medium proteolytic activity, the degradation of casein was seen by the appearance of a peak with migration time similar to alpha s1-I casein, a peptide normally produced by chymosin.

Bacteriological Techniques

False positive diagnosis of meningococcal infection by the IS1106 PCR ELISA.

At a time when optimal case ascertainment for meningococcal infection is a high priority, the need for non-culture case confirmation, in particular by DNA amplification, is seen as being of vital importance to assist contact management and cluster recognition. A solution hybridisation assay with colorimetric microtitre plate detection (polymerase chain reaction-enzyme-linked immunosorbent assay (PCR ELISA)¿ has been developed using the multicopy insertion sequence IS1106 which had reportedly achieved a specificity of 100% and was described as being meningococcal specific. This PCR ELISA assay was evaluated on specimens from over 5000 patients at the national Meningococcal Reference Unit (MRU) between late 1995 and early 1997 and was found to be highly sensitive. Insertion sequences, however, are genetically mobile with the ability to spread between species and even genera. During the evaluation period of the IS1106 PCR ELISA a number of false positives proved to be caused by organisms other than N. meningitidis were recorded resulting in the withdrawal of this assay as a front line screening assay for routine confirmation of meningococcal infection.

Bacteriological Techniques