Early Childhood Caries and Immunonutritional Status in Preschool Children: A Retrospective Comparative Study of the HALP Score and Hematological Biomarkers

Background: Early childhood caries (ECC) is a common chronic disease in children and has been associated with systemic inflammatory and nutritional alterations. The hemoglobin, albumin, lymphocyte, and platelet (HALP) score reflects immunonutritional status. This study investigated the associations of the HALP score and hematological parameters with ECC, caries burden, and periapical disease severity. Methods: This retrospective comparative study included 126 preschool children: 97 with ECC and 29 caries-free controls. Participants were further classified into low (Periapical Index (PAI) 1–3) and high (PAI 4–5) periapical disease severity groups according to the highest Periapical Index score. The HALP score was calculated using the standard formula. Statistical significance was set at p < 0.05. Results: No statistically significant association was detected between the HALP score and ECC, dmft, or periapical disease severity (p > 0.05). Albumin levels were higher in the ECC group than in controls (p < 0.001). Neither the HALP score nor its individual hematological components were associated with caries burden in negative binomial regression analyses (p > 0.05). Greater caries burden was independently associated with severe periapical disease (Odds Ratio (OR) = 1.19, 95% Confidence Interval (CI): 1.09–1.30, p < 0.001), whereas hemoglobin was not (p = 0.052). Conclusions: No statistically significant association was detected between the HALP score and ECC status, caries burden, or periapical disease severity. Although albumin levels differed between children with ECC and caries-free controls, neither the HALP score nor its individual hematological components were independently associated with caries burden. Larger prospective multicenter studies are needed to validate these findings.