Detection of Streptococcus mutans and Streptococcus sobrinus and Their Association with Oral Microbiome Stressors in 6–18-month-old Infants

Abstract

A bstract Aim To determine the presence of Streptococcus mutans (S. mutans) and Streptococcus sobrinus (S. sobrinus) and their association with extrinsic and intrinsic variables in 6–18-month-old infants. Methods This was an analytical, cross-sectional study of 65 6–18-month-old infants who visited the Centers for Early Childhood in Buenos Aires City. Three groups were established according to the presence of teeth—group I (GI)—edentulous infants, group II (GII)—infants with 1–8 teeth, and group III (GIII)—infants with 9–16 teeth. Data on the variables, diet, use of artificial teats, and oral hygiene were gathered using a self-administered questionnaire. An oral examination was performed according to the International Caries Detection and Assessment System (ICDAS II) criterion. A saliva sample was taken by aspiration with a sterile plastic syringe. Cariogenic Streptococci (CS) were counted using the adherence test in modified gold broth (AT-MGB). Molecular detection and quantification were performed by quantitative polymerase chain reaction (qPCR) (gtfB, gtfT, and tuf). Results A total of 12% of infants received oral hygiene, 38% used bottles, 30% used pacifiers, and 55% had sugar intake. S. sobrinus and S. mutans were detected in 57.1 and 28.6% of the children with caries, respectively. Groups I, II, and III had CS counts of log 2, 3.4, and 3.7, respectively. S. sobrinus was detected in 26.7% of GI, 52.9% of GII, and 85.7% of GIII, while S. mutans was detected in 13.3%, 35.3%, and 57.7%, respectively. Conclusion The prevalence of S. sobrinus was higher than S. mutans in all groups. The presence of CS was significantly associated with sugar intake. No association was found between S. mutans and S. sobrinus and the presence of caries, hygiene habits, or use of artificial teats. Clinical Significance This study supports the role of diet in developing a cariogenic biofilm in children under 2 years of age. How to cite this article Cornejo CF, Soken LJ, Salgado PA, et al. Detection of Streptococcus mutans and Streptococcus sobrinus and Their Association with Oral Microbiome Stressors in 6–18-month-old Infants. Int J Clin Pediatr Dent 2023;16(1):68-73.

The Associations between Snack Intake and Cariogenic Oral Microorganism Colonization in Young Children of a Low Socioeconomic Status

“…Previous studies have presented mixed results regarding the association between sugar intake or sweetened food/beverages and the presence of S. mutans in saliva or plaques. Some studies have reported positive associations [ 19 , 20 , 22 , 25 ], while others found no association or low correlation [ 21 , 24 ]. In our cross-sectional analysis, a trend, albeit non-significant, of positive associations between sweet index scores and S. mutans carriage in saliva and plaques was observed at 12 and 18 months of age.…”

“…Sweets and desserts continue to be the primary components of snacks in children [ 14 ], and the relationship between snack intake and ECC may be partially attributed to the ability of sugary snacks to modulate the presence and colonization of cariogenic oral microorganisms. These snacks with a high sugar content provide fermentable carbohydrates that stimulate bacterial growth and alter the pH levels in the oral environment, thereby promoting bacterial biofilm formation [ 18 , 19 ]. There, snack intake, particularly those rich in sugars, may play a role in fostering the growth of cariogenic microorganisms and contributing to the development of ECC.…”

“…Several studies have investigated the associations between sugary snacks and S. mutans carriage in young children, yielding mixed results [ 19 , 20 , 21 , 22 , 23 , 24 , 25 ]. However, there are gaps in our understanding, particularly regarding the relationships between snack intake and other cariogenic microorganisms, such as Candida .…”