The aim of this retrospective study was to evaluate the dental treatments received under general anesthesia (GA) in pre-school children and school children with special healthcare needs (n = 263) compared with healthy controls (n = 62). In order to analyze the impact of pre-existing cofactors on oral health, children were divided into the following groups: heart disease, cancer, syndromic disease, and other diseases as well as in- and outpatient healthy children. Caries experience (dmf-t/DMF-T) before GA (impulse 1), waiting time, and dental treatment under GA (impulse 2) were determined. Pre-school children showed a higher caries experience (mean ± standard deviation; 8.3 ± 4.8) compared to schoolchildren (6.9 ± 4.3). Predominantly, early childhood caries (ECC) of type 1 were detected. From all groups with special healthcare needs, children with cancer revealed the highest Significant Caries Index (17.0 ± 2.0), followed by other diseases (14.6 ± 2.6), syndromic disease (14.3 ± 1.8), and heart disease (13.8 ± 2.7). Overall, 2607 dental procedures were performed under GA with a mean of 8.0 ± 6.5 dental measures per child. Within the limitations of this study, the data exhibited independent of pre-existing cofactors and age high caries risk in all patient groups showing a high need for treatment.