correlation between dmft index andoccurrence of lactobacillus spp. in the oral cavity

the human oral cavity includes different bacterial community. advantage anddisadvantage of these bacteria depend on their ability to adhere to the toothsurfaces. some microbiota could cause oral disease, however, some of them inhibitformation of biofilm on teeth and therefore prevent dental caries. the present studywas undertaken to investigate on the dmft index (d: decay, m: missing, f: filling,t: teeth) and the occurrence of different species of lactobacillus, as the mostimportant oral microbiota. ninety swab samples were collected from saliva andteeth of the patients and subjected to microbiological analysis. along withphenotypic and genotypic identifications of the isolates, the dmft index of eachpatient was measured to determine the oral conditions. to continue the study theantibacterial effect of five commercial toothpastes was evaluated on the isolates.the results obtained indicated that the frequency of occurrence of l.plantarum,l.rhamnosus and l.mali was high in the patients with a low dmft score andl.otakiensis, l.diolivorans and l.kefiri was high in the patients with a high dmftscore. althoughall isolates were susceptible to the commercial tooth pastes,l.plantarum and l.rhamnosus were relatively more sensitive. based on the results,human oral health might be affected by the population of lactobacillusspp.furthermore, use of toothpastes without adequate information concerning to theirantimicrobial effects might eliminate the population of beneficial oralmicrobiotaand hence increase the risk of oral diseases.