Caries risk in toddlers: assessing oral health, microbial factors, and maternal transmission

Caries risk begins early in life, yet few studies use intraoral cameras to assess risk in toddlers or examine multiple contributing factors. This study aimed to address this gap and conduct intraoral camera-based assessment of caries and evaluate multiple toddler risk factors, including microbial profiles, oral hygiene practices, and potential maternal transmission.

Cross-sectional data from 21 maternal-child dyads included intraoral camera assessments coded with an adapted International Caries Detection and Assessment System, saliva-based microbial tests for Streptococcus mutans (SM) and Lactobacillus (LB), and validated surveys of hygiene practices.

Among toddlers (N = 21; mean age 3.9 years), intraoral camera use was well tolerated and produced images adequate for assessment. Reliability was good for sound teeth [Intraclass correlation coefficient (ICC) = 0.80], moderate for initial caries (ICC = 0.72), and poor for moderate-to-severe caries (ICC = 0.13). Most teeth were sound (89.0%), with 9.8% mild and 1.1% moderate decay. SM was detected in 9/20 (45.0%) and LB in 4/21 (19.0%) of toddlers. While 81% brushed twice daily, few flossed (14.3%) or used mouthwash (19%); 42.1% consumed soda at least weekly and 19% ate fast food weekly. More frequent brushing was associated with lower SM (Cramer's V = 0.54; p = .02) and LB (V = 0.48; p = .043). Mothers (N = 21; mean age 32.1) had 38.0% of teeth coded as sound, 45.0% with initial caries, and 14.0% with moderate-to-severe decay; 9/21 (42.9%) tested positive for LB and the same proportion tested positive for SM. Most brushed twice daily (81%), with 47.6% flossing and 38.1% using mouthwash. Maternal and toddler brushing frequency (V = 0.68; p = .02), fast-food intake (V = 0.56; p = .01), and microbial positivity (SM: V = 0.93; p = .001; LB: V = 0.54; p = .02) were strongly related.

Intraoral cameras with adapted ICDAS scoring were feasible for assessing caries risk in toddlers. Significant concordance between maternal and child microbial profiles suggests a potential maternal influence on early caries risk. Larger longitudinal studies are needed to clarify transmission pathways and inform prevention strategies.