2 research outputs found
Inhibitory effect of sodium fluoride and chlorhexidine on the growth of oral lactobacilli
The accumulation of microorganisms in dental plaque is related to the etiology of caries and periodontal disease, with a high prevalence worldwide. The prophylactic measures include the use of chemical agents as NaF and chlorhexidine. Lactic acid bacteria are members of the normal microbiota of the oral cavity being discussed with regard to their beneficial or detrimental effect in this environment. The present study was performed to determine the growth of some species of Lactobacillus at different concentrations of NaF and chlorhexidine. The strains were isolated from
both caries-free and caries patients. Their growth parameters were evaluated by the application of the Gompertz model to the experimental data of optical density as a measurement of growth. The degree of inhibition of the growth of all of the lactobacilli studied was different, depending on each particular strain. NaF at 1 mmol·L–1 inhibited between 5% and 46%, at 5 mmol·L–1 between 13% and 65%, and at 20 mmol·L–1 between 57% and 84%. CHX at higher concentrations (197 and 98 mmol·L–1) showed a complete inhibition of some of the strains. The significance of the results was evaluated by the application of a multivariate analysis and also compared with the inhibition of pathogenic Streptococcus mutans and with lactobacilli strains from collection cultures.L’accumulation de micro-organismes dans la plaque dentaire est reliĂ©e Ă l’apparition des caries et des maladies parodontales, avec une prĂ©valence Ă©levĂ©e partout dans le monde. Les mesures prĂ©ventives englobent l’utilisation d’agents chimiques comme le fluorure de sodium (NaF) et la chlorhexidine (CHX). Les bactĂ©ries lactiques font partie de la microflore normale de la cavitĂ© orale et ont des effets bĂ©nĂ©fiques ou nĂ©fastes sur cet environnement. La prĂ©sente Ă©tude a Ă©tĂ© accomplie afin de dĂ©terminer la croissance de certaines espèces de lactobacilles Ă diffĂ©rentes concentrations de NaF et de CHX. Les souches ont Ă©tĂ© isolĂ©es de patients avec ou sans caries. Leurs paramètres de croissance ont Ă©tĂ© Ă©valuĂ©s en appliquant le modèle de Gompertz aux donnĂ©es expĂ©rimentales de densitĂ© optique (D.O.) afin d’obtenir une mesure de la croissance. Le niveau d’inhibition de la croissance des lactobacilles Ă©tudiĂ©es diffĂ©rait selon la souche. 1 mmol·L–1 de NaF a inhibĂ© entre 5 % et 46 %, entre 13 % et 65 % pour 5 mmol·L–1 et entre 57 % et 84 % pour 20 mmol·L–1. Des concentrations Ă©levĂ©es de CHX (197 et 98 mmol·L–1) ont complètement inhibĂ© certaines souches. La signification des rĂ©sultats a Ă©tĂ© Ă©valuĂ©e par une analyse multivariable de mĂŞme que par la comparaison avec l’inhibition de Streptococcus mutans pathogènes et de souches de lactobacilles issues de cultures de collections.Fil: Ahumada Ostengo, MarĂa Del Carmen. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Wiesse, Birgitt. Medical University of Gottinger. Institute of Biometry; AlemaniaFil: Nader, Maria Elena Fatima. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentin