Purpose: The aim of this retrospective cross-sectional study was to detect dental health and dental treatment under general anaesthesia, as well as associations to selected parameters in a patient cohort with different disabilities. Material and Methods: Patients with disabilities, including mental, physical, combination of mental and physical as well as psychiatric disability, which received dental rehabilitation under general anaesthesia between 1 January 2002 and 31 December 2011 were included. Based on the available patients' records, findings of dental examination (Decayed-, Missing- and Filled-teeth index [DMF-T]), treatment documentation as well as further specific factors including the presence of preoperative dental examination or radiographs were analysed. Statistical analysis was conducted using Mann-Whitney U test, Kruskal–Wallis test, analysis of variance (ANOVA), chi-squared or Fisher's exact test (p <0.05). Results: A total of 464 patients were included. An overall DMF-T of 12.3 ± 7.5 (D-T of 5.8 ± 5.1) and a dmf-t of 9.2 ± 5.0 (d-t of 7.5 ± 4.5) were found. Patients with psychiatric disabilities showed worst dental health. About half of patients (56%) received a professional tooth cleaning. A tooth extraction was executed at 70% of patients, with 3.3 ± 4.5 teeth each patient. Nearly no patient received periodontal or endodontic treatment. Patients with a preoperative dental examination received statistically significantly less tooth extractions compared to patients without preoperative dental examination (2.7 ± 3.7 vs 4.5 ± 5.8). Conclusion: Patients with different disabilities show high dental treatment need and require improved dental care. Thereby, the preoperative dental examination might avoid unnecessary tooth extractions and is therefore strictly recommended.