Some oral conditions can have psychosocial consequences that affect children's daily life and well-being. To create a structural model for the determination of dental caries, molar-incisor hypomineralization (MIH), and the impact of these conditions and socioeconomic status on schoolchildren's oral health-related quality of life (OHRQoL). A representative cross-sectional study was conducted in Lavras, Brazil, with 1181 female and male schoolchildren 8-9 years of age. OHRQoL was measured using the Brazilian version of the CPQ8-10. Clinical examinations were performed by a calibrated dentist for the diagnosis of dental caries (WHO) and MIH (EAPD). Parents/caregivers answered questionnaires addressing the child's medical history and socioeconomic status. Data were analyzed using structural equation modeling. The model revealed that greater MIH severity (β=.874; p < .001) and worse socioeconomic status (β=-.060; p=.001) were associated with a greater number of teeth with caries experience. The higher the number of teeth with caries experience (β=.160; p=.007) and worse socioeconomic status (β=-.164; p < .001), the greater the negative impact on OHRQoL. The model created showed that dental caries and socioeconomic status had a direct negative impact on the OHRQoL of schoolchildren and MIH had an indirect impact mediated by the occurrence of caries experience.