Comparative analysis of three commercial saliva testing kits with a standard saliva buffering test

Abstract

Background: In 1959, Ericsson developed a laboratory buffer capacity test. Because the Ericsson test is not practical for use as a chair-side test, commercially available saliva buffering capacity tests have been developed for use in the dental office. The purpose of this study was to evaluate the correlation between a modified Ericsson test and three commercially available quantitative and colourimetric tests. Methods: Stimulated saliva (by chewing paraffin wax) was collected from 113 patients. Individual saliva buffering capacity was assessed with the following four different methods: modified Ericsson test; quantitative test using a hand-held pH meter; paper strip; or liquid colourimetric test. The correlations of ranking results among the different tests were analysed using the Spearman Rank Correlation Test, p < 0.001. Results: Spearman Rank Correlation indicated significant positive coefficients between the modified Ericsson test and the quantitative test (ρ = 0.857), the paper strip colourimetric test (ρ = 0.621) and the liquid-type colourimetric test (ρ = 0.689). Conclusion: The detection level of medium and high buffering capacity was test dependent. The quantitative test using a hand-held pH meter showed a stronger positive correlation with the modified Ericsson test. The qualitative tests seemed less reliable, particularly for patients classified as having a medium buffering capacity. © 2008 Australian Dental Association.