Long-term oral and dental effects in childhood acute lymphoblastic leukemia survivors: a cross-sectional study comparing early and late post-treatment periods

Background Childhood cancer survivors face significant long-term oral health challenges following antineoplastic treatment. This study aimed to evaluate salivary function, caries experience, and dental developmental anomalies in children who completed acute lymphoblastic leukemia (ALL) treatment, comparing early survivors (24–36 months post-treatment) with late survivors (37–60 months post-treatment). Methods This cross-sectional study included 38 ALL survivors (aged 5–18 years) and 20 healthy sibling controls. Salivary flow rate (SFR) and pH were measured using standardized protocols. Dental caries was assessed using the International Caries Detection and Assessment System (ICDAS II) and DMFT/dft indices. Dental developmental anomalies were identified through panoramic radiographic examination. Comparisons were performed using the Mann-Whitney U test, the Kruskal-Wallis test, and the chi-square test, with multivariable linear regression analysis used to identify independent predictors of caries outcomes. Results Dental developmental anomalies were significantly more prevalent in survivors (84.2%) compared with controls (10%; p < 0.001). Microdontia was the most common anomaly (34.5%), followed by root malformation (22.4%) and taurodontism (13.8%). Early survivors demonstrated significantly lower SFR (median 2.75 vs 4.00 mL/min; p = 0.017), higher mean ICDAS scores (median 1.38 vs 0.60; p = 0.007), and elevated DMFT/dft indices (median 12.0 vs 7.0; p = 0.002) compared with late survivors. Multivariable regression identified age and treatment timing as independent predictors of ICDAS scores (adjusted R² = 0.285, p = 0.014), while treatment timing independently predicted DMFT/dft scores (B = − 4.522, p = 0.003). Conclusions ALL survivors exhibit a high prevalence of dental developmental anomalies and suggest a trend toward improvement in oral health parameters with increasing time since treatment completion. The 24–36 month post-treatment period may represent a particularly vulnerable phase, warranting closer dental monitoring. These findings may help inform the development of structured, risk-stratified dental follow-up approaches for childhood cancer survivors.