Correlations between Numbers of Microf lora in Plaque and Saliva

Abstract

An epidemiologic investigation to reliably identify caries-susceptible subjects by microbiological and chemical assessment of plaque and saliva is currently in progress. As part of that study, the numerical relationships of mutans streptococci, lactobacilli and total viable microflora in plaque and saliva among 12- to 15-year-old children in a fluoridated community were determined. Paraffin-stimulated whole saliva and pooled dental plaque were collected. Each sample was suspended in reduced transport fluid, chilled on ice, and assayed. The bivariate normal distribution was found to be a suitable model for the distribution of the pairs [numbers of bacteria in plaque (log₁₀), numbers of bacteria in saliva (log₁₀)]. Statistically significant positive correlations were found between numbers of mutans streptococci in plaque and saliva, and between lactobacilli in plaque and saliva.

Enumeration of Salivary Streptococci and Lactobacilli in Children with Differing Caries Experiences in a Rural Indian Population

“…Questions concerning reliability of saliva over plaque or oral swab samples can be raised. e reports of Mundroff et al (1990) and Dasanayake et al (1995) nullify this doubt as they found that detection of Streptococci and Lactobacilli in stimulated saliva was in excellent agreement with either pooled plaque or oral swab samples [29,30]. Studies have shown that differences in culture may result when different media are used [31,32].…”

Associations between Microbiological and Salivary Caries Activity Tests and Caries Experience in Hungarian Adolescents

“…Discussions in the scientific literature concerning the reliability of plaque and/or salivary microbiology is considered of reference value, however, in the course of large-scale epidemiological studies not always feasible. Studies found a statistically significant correlation between the numbers of microorganisms in plaque and saliva in 12-to 14-year-old children [Mundorff et al, 1990], and others think that the number of mutans streptococci or lactobacilli in a total dental plaque sample does not explain the variation in caries better than the numbers in stimulated whole saliva [Sullivan et al, 1996]. Further, comparative studies between commercial kits working with the dip-slide test and conventional plate counts for determination of mutans streptococci report a significant correlation of the two methods [Emilson and Krasse, 1986], and recommend the dip-slide method -used in our study -because of its practicability, reliability and usefulness in clinical routine [Kneist et al, 1996].…”

Investigation of Microbiological Methods to Estimating Individual Caries Risk: Evaluation of Sampling Methods and Materials.

“…These findings strongly suggest that whole stimulated saliva is not suitable as a sample for the caries risk assessment of individualsand that a plaque sample is essential for it because the tooth surfaces constitute the natural habitat of mutans streptococci. Many epidemiological studies have shown positive correlations between levels of mutans streptococci in saliva and plaque (16)(17)(18), and the enumeration of these cariogenic bacteria therefore have often been done with stimulated saliva samples, which are easier to obtain. However, data in those epidemiological studies also indicate that an individual ratio of MS levels in saliva and plaque significantly differs among subjects.…”