Identification of Streptococcus mutans and Lactobacillus spp. in a Community on the Amazon Riviera: a Cross-Sectional Study
DOI:
https://doi.org/10.15517/mg02sz23Keywords:
Oral microbiome; Dental caries; Streptococcus mutans; Lactobacillus spp.; Peruvian Amazon.Abstract
Dental caries is a chronic and infectious disease of high global prevalence, particularly affecting vulnerable populations such as riverine communities in the Peruvian Amazon. Its etiology is associated with an imbalance in the oral microbiome, where Streptococcus mutans and Lactobacillus spp. play a key role. This study aimed to determine the prevalence of these bacteria and their association with the DMFT index, salivary pH, and sociodemographic variables. A cross-sectional study was conducted among 65 adults aged 18 to 65 years from Amazon River communities, evaluated through the Medical Program Esperanza Amazónica – Vine Trust. Sociodemographic data were collected, the DMFT index was calculated, and saliva samples were analyzed to identify S. mutans and Lactobacillus spp. using selective culture media. Salivary pH was measured digitally. Non-parametric statistical tests (Chi-square and Spearman) were applied, with a significance level set at p<0.05. Lactobacillus spp. was detected in 63.1% of participants and S. mutans in 24.6%. A significant positive correlation was found between both bacteria and the DMFT index (S. mutans: rho=0.638; Lactobacillus spp.: rho=0.484; p<0.001). Coinfection was associated with a significantly higher DMFT score (p=0.03). Although no significant correlations were found with salivary pH or sex, a trend toward greater bacterial colonization was observed in women and in more acidic environments. The presence of S. mutans and Lactobacillus spp. was associated with greater caries severity, with coinfection representing a potential additional risk factor. These findings highlight the need for targeted preventive interventions in Amazonian communities.
Downloads
References
Doughty J., Macdonald M.E., Muirhead V., Freeman R. Oral health-related stigma: describing and defining a ubiquitous phenomenon. Community Dentistry and Oral Epidemiology. 2023; 51 (6): 1078-83.
De Paiva Buischi Y., De Campos Kajimoto N., Funari S.L., Kimathi M., Loomer P.M. Improving oral health of adolescent girls in Kenya through education: an observational study. International Journal of Dental Hygiene. 2023; 21 (3): 575-81.
Spatafora G., Li Y., He X., Cowan A., Tanner A.C.R. The evolving microbiome of dental caries. Microorganisms. 2024; 12 (1): 121.
Liu Y., Daniel S.G., Kim H.E., Koo H., Korostoff J., Teles F., et al. Addition of cariogenic pathogens to complex oral microflora drives significant changes in biofilm compositions and functionalities. Microbiome. 2023; 11 (1): 123.
Tuganbaev T., Yoshida K., Honda K. The effects of oral microbiota on health. Science. 2022; 376 (6596): 934-6.
Tandon A., Srivastava A., Singh P., Jaiswal R., Saha S., Bordoloi B. Beyond decay: exploring the age-associated variations in Streptococcus mutans and Lactobacillus in dental caries. International Journal of Clinical Pediatric Dentistry. 2024; 17 (9): 993-8.
Chen X., Daliri E.B., Chelliah R., Oh D.H. Isolation and identification of potentially pathogenic microorganisms associated with dental caries in human teeth biofilms. Microorganisms. 2020; 8 (10): 1596.
Martignon S., Roncalli A.G., Alvarez E., Aránguiz V., Feldens C.A., Buzalaf M.A.R. Risk factors for dental caries in Latin American and Caribbean countries. Brazilian Oral Research. 2021; 35 (Suppl 1): e053.
Jalal Hussein F., Sherdl Saleem S., Abdulaziz Merdad K. Relationship between dental caries experience and the levels of Streptococcus mutans and Lactobacillus in saliva of pregnant women. Cellular and Molecular Biology. 2023; 69 (8): 148-55.
Wen Z.T., Huang X., Ellepola K., Liao S., Li Y. Lactobacilli and human dental caries: more than mechanical retention. Microbiology. 2022; 168 (6).
Yu S., Ma Q., Li Y., Zou J. Molecular and regulatory mechanisms of oxidative stress adaptation in Streptococcus mutans. Molecular Oral Microbiology. 2023; 38 (1): 1-8.
Steier L., Sidhu P., Qasim S.S., Mahdi S.S., Daood U. Visualization of early bacterial colonization in dentin using fluorescence-inducing headlight for improved diagnosis. Photodiagnosis and Photodynamic Therapy. 2022; 38 (102732): 102732.
Chianca G.C., Antunes L.A.A., Ornellas P.O., Neves F.P.G., Póvoa H.C.C., Iorio N.L.P.P. Virulence of Lactobacillus spp.misidentified as Enterococcus faecalis in carious dentin of children. Acta Odontologica Scandinavica. 2022; 80 (1): 21-8.
Bahurupi M.P., Gupte T.S., Grace B., Sawant A.S., Sonawane N.S. Comparative evaluation of changes in salivary flow rate, pH, and Streptococcus mutans levels in children under fixed and removable space maintainer therapy. Journal of Indian Society of Pedodontics and Preventive Dentistry. 2022; 40 (4): 404-9.
Danaei M., Mollaali M., Fakharmohialdini V., Poureslami H., Sajadi F.S., Gisour E.F., et al. Molecular and microbial detection of Streptococcus mutans and lactobacilli in dental caries: an experimental study in Iranian children aged 5-9 years. Clinical and Experimental Dental Research. 2024; 10 (6): e70039.
Lin P.Y., Mai H.Y., Wu C.Y., Lin H.C., Chi L.Y. Association between untreated caries and cariogenic bacteria in Taiwanese adolescents. Journal of Dental Sciences. 2024; 19 (4): 2027-34.
Pecci-Lloret M.P., Linares-Pérez C., Pecci-Lloret M.R., Rodríguez-Lozano F.J., Oñate-Sánchez R.E. Oral manifestations in pregnant women: a systematic review. Journal of Clinical Medicine. 2024; 13 (3).
Cerutis D.R., Russell S.L., O'Malley L. Women in oral epidemiology: 2022. Frontiers in Oral Health. 2023; 4: 1297040.
Zhou G., Shu X., Long Y., Cao Y., Wang J., Liao G., et al. Dental caries and salivary alterations in patients with type 2 diabetes: a systematic review and meta-analysis. Journal of Dentistry. 2024; 150 (105321): 105321.
Szkaradkiewicz-Karpinska A.K., Zaba C., Tezyk A., Greczka G., Szkaradkiewicz A. Salivary glucose levels and pH in healthy adults with dental caries. Journal of Physiology and Pharmacology. 2024; 75 (5).
Soundaram B., Murali C.R., Ajithkumar M., Anjali A., JothiPriya D., Vikraman S. Evaluation of oral microflora related to dental caries and salivary pH in patients with type II diabetes. Journal of Pharmacy and Bioallied Sciences. 2024; 16 (Suppl 2): S1843-9.
Rai A., Sundas S., Dhakal N., Khapung A. Evaluation of dental caries using ICDAS and WHO criteria: a comparative study. International Journal of Paediatric Dentistry. 2024; 34 (1): 77-84.
Gracco A., De Stefani A., Bruno G. Influence of new technologies in dental care: a public health perspective. International Journal of Environmental Research and Public Health. 2023; 20 (7).
Evaristo-Chiyong T.A., Mattos-Vela M.A., Gómez-Meza D.N., Lamas-Lara V.F., Rodríguez-Vargas M.C., Agudelo-Suárez A.A. Validation of the Health Literacy in Dentistry scale (HeLD-14) among Peruvian adults: a cross-sectional study. Journal of International Society of Preventive and Community Dentistry. 2025; 15 (1): 80-90.
Published
Issue
Section
License
Copyright (c) 2026 Gerson Arthur Perez-Salazar, Cristian Payano-Pashanasi, Martín Andrés Chávez-Méndez, Myriam Angélica De la Garza-Ramos, Guillermo Cano-Verdugo.
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
ODOVTOS - Int. J. Dent. Sc. endorses CC BY-NC-SA
This license enables reusers to distribute, remix, adapt, and build upon the material in any medium or format for noncommercial purposes only, and only so long as attribution is given to the creator. If you remix, adapt, or build upon the material, you must license the modified material under identical terms. CC BY-NC-SA includes the following elements:
BY: credit must be given to the creator.
NC: Only noncommercial uses of the work are permitted.
SA: Adaptations must be shared under the same terms.
