Purpose: To document mid- and long-term changes in oral health-related quality of life (OHRQoL) following dental intervention in a sample of restorative treatment-naïve children receiving different levels of care, with and without general anesthesia (GA). Methods: This prospective cohort study followed 132 children. Parents completed the pediatric OHRQoL instrument (POQL) before, 16 weeks after (i.e., posttreatment), and 18 to 45 (mean equals 29.5) months after (i.e., follow-up) child receipt of treatment. Parents provided child demographic and oral health information. The number of restored surfaces and anesthesia type were abstracted from dental records. The mean differences in POQL scores were compared across groups. Results: The sample was 49 percent female (age range equals four to 12 years; mean±standard deviation equals 5.8±1.8). Overall, from pretreatment to posttreatment, mean POQL scores decreased by 4.5 points (P<0.001), representing improved OHRQoL. Only among children with 10 or more surfaces restored or who received GA did follow-up POQL scores remain significantly lower than pretreatment scores (mean difference equals -7.4 and -8.0, respectively, P<0.01). Overall, follow-up scores were significantly higher than posttreatment scores, representing a decline from the initial improvement. Conclusions: Regardless of disease severity, children experience an immediate improvement in OHRQoL following restorative treatment. Improvements in OHRQoL are sustained over the long-term only among children with more extensive pretreatment needs.