Identification and microbiological characterization of Streptococcus mutans in mother-child saliva, Riobamba, Ecuador

Abstract

Introduction. Dental caries is one of the most frequent infectious diseases. Streptocococcus mutans is the main etiological agent associated with the onset of this disease. Objective. To identify and microbiologically characterize the presence of S. mutans in saliva samples from mothers and children of Centros de Desarrollo Infantil del Gobierno Autónomo Descentralizado Municipal, Riobamba, Ecuador. Methodology. Field study, with a non-experimental design, cross-sectional and quantitative approach. The sample consisted of 111 children, aged between 1 and 4 years, selected from 5 child development centers belonging to Gobierno Autónomo Descentralizado Municipal, Riobamba, Ecuador. In addition, 27 mothers of these children participated in the study. Unstimulated saliva samples were collected and processed at the laboratory of Universidad Nacional de Chimborazo. Cultures were performed on agar mitis salivarius to count the colonies that presented the typical characteristics of S. mutans, followed by their identification with conventional biochemical tests. The results obtained were statistically analyzed using absolute and relative frequencies. Results. Out of a total of 111 children screened, S. mutans was detected in 55 (49.5%) of them. Among them, 39 (79%) showed a medium cariogenic risk. Only 27 of the 55 mothers agreed to collaborate in the isolation of the bacteria, 9 (33.3%) presented the microorganism. In relation to their cariogenic risk, it was observed that 7 (25.9%) had a medium risk, with values between 8 and 70 CFU. Conclusion. The results obtained indicate an increased risk of dental caries among the child population under study, revealing that 49.5% of the cases examined presented the presence of S. mutans. These findings can play a crucial role as indicators to guide the implementation of strategies in oral health prevention programs.