Abstract
Assess the association between dental caries clinical stage, lesion location, and oral health-related quality of life (OHRQoL) in preschool children. A cross-sectional study was conducted with a representative sample of 643 caregiver-child dyads aged 0-5 years. Children underwent oral examinations using the International Caries Detection and Assessment System (ICDAS) and the International Caries Classification and Management System (ICCMS™) criteria to classify caries stage and lesion location. Traumatic dental injuries (TDI) were assessed using Andreasen's classification. Caregivers completed the Early Childhood Oral Health Impact Scale (ECOHIS). Weighted Kappa coefficients assessed intra- and inter-examiner reliability. Negative binomial regression models, adjusted for sociodemographic variables and clinical factors, estimated the association between caries stage/location and ECOHIS scores. The prevalence of dental caries (all stages) was 72.6%, with 27.3% of children caries-free. Overall, 48.2% of caregivers reported at least one oral health impact in their child's life (ECOHIS ≥ 1). Children with extensive lesions (stage C) had significantly worse total and domain ECOHIS scores than caries-free children (p < 0.001), regardless of lesion location. Moderate lesions (stage B) affected OHRQoL only when present in both anterior and posterior teeth (RR = 1.54; p = 0.045). Older age, public school attendance, and household crowding were also associated with poorer OHRQoL. The presence of TDI was independently associated with poorer OHRQoL (RR = 1.63; p < 0.001). These findings highlight the need for targeted, patient-centred interventions to address caries burden effectively.