colonial morphology and biochemical analysis in S.mutans identification

Objectives: Mitis Salivarius Agar added of Bacitracina and Saccharose (MSBS) is frequently used as a little selective for streptococcus growth of the group mutans. The colonial morphology after incubation is usually considered as determinate factor for characterization of S. mutans. The goal of this work was to compare if this morphology, indicative of S.mutans, confirms through biochemical proofs standardized in isolated of children with caries activity varied of a specific population. Methods: Thirty saliva samples of children, with age between 5 and 10 years, attended in to Clínica de Odontopediatria da Universidade Federal do Paraná were used. The samples were cultivated in MSBS to 37ºC for 48 hours in microaerofilia. After incubation, they were isolated morphologically indicative colonies of S. mutans and afterwards analyzed by biochemical proofs. Results: The tests confirmed 50% of concordance between colonial morphology and biochemical analysis positive for S. mutans. Conclusion: The results shows that only the analysis of the colonial morphology in MSBS should not be considered conclusive for S.mutans identification. Being this way, the accomplishment of biochemical proofs would be a safe method for the complementation of this identification.