BACKGROUND: Caries is a multifactorial degenerative disease, and it is the most common chronic disease during childhood. Few studies have assessed the effects of breastfeeding and bottle feeding on children's dental caries, also taking into account the duration of both options. We investigated whether the infant feeding duration and feeding methods (breast, bottle or both) are risk factors for dental caries in childhood. METHODS: Our study included 210 children from 2 to 6 years old and it was carried out in the Department of Pediatric Dentistry of Borgo Cavalli (Treviso, Italy). The average number of decayed, missing, and filled primary tooth surfaces (DMFT) were investigated by analyzing the medical histories. Data collection was conducted from September 2021 to July 2022. Data analysis was performed using the statistical program R (R Foundation for Statistical Computing, Vienna, Austria). First, an analysis was performed to verify the database using a graph. We used the negative Poisson and Binomial count model for the data. Next, the verification of which covariables were significant was performed, finally the conclusions were obtained. RESULTS: By dividing the population according to the type of feeding, we saw that most of the children participating in the study had between 3 and 7 cavities. By analyzing the length of feeding, we saw that the average duration was between 10 and 20 months. Due to the P values, we concluded that the total duration of feeding variable was not significant in explaining the event of interest and, therefore, only the variable type of feeding (artificial and natural) was significant because the P value was below the 5% significance level. Finally, we concluded that natural type breastfeeding increases the average amount of caries by 1.29 times, or 29% more than artificial feeding. CONCLUSIONS: Compared to bottle-feeding, breastfeeding increases the risk of caries at an early age; however, there is no correlation between duration and occurrence of caries. Meanwhile, considering health benefits, dental professionals should not discourage breastfeeding; as a matter of fact, promoting breastfeeding has many benefits for infants and mothers, provided that it is associated with proper oral hygiene.