Exploring Dental Caries and Associated Factors in 3-Year-Old Iranian Children: An Application of Random Forest for Zero-Inflated Poisson Process.

Background: Dental caries, caused by bacterial activity leading to tooth decay, has a profound impact on children's quality of life. This study aimed to investigate factors associated with dental caries in 3-year-old Iranian children. Methods: A cross-sectional study was conducted involving 815 three-year-old children who were referred to healthcare centers in the southern region of Tehran Province, Iran. Truncated random forest, traditional random forest, and a log-linear model were employed, utilizing the number of dental caries (including excess zeros) as the outcome variable. Predictors included sex, tooth brushing, dental flossing, sweet consumption, dental visits, and parental education level. Results: The log-linear model's rate ratio (RR) indicated that boys were more likely to have at least 1 decayed tooth compared to girls (RR, 1.11). Dental floss usage significantly reduced childhood dental caries (RR, 2.74). Variable importance analysis from 2 random forests identified dental floss usage, dental visits, and the father's educational level as the most impactful factors on childhood caries. Results based on mean squared error (MSE) demonstrated that the truncated random forest (MSE, 0.002) outperformed the log-linear model (MSE, 0.959) and exhibited similar performance to the traditional random forest model (MSE, 0.006). Conclusion: The truncated random forest model demonstrated superior performance compared to traditional random forest and log-linear models. From a clinical perspective, promoting knowledge and practices related to good oral health habits in parents and their children emerges as a crucial strategy for reducing the risk of childhood caries.