Reliability and self-perception of semi-automatically assessed orthodontic treatment need in elderly patients undergoing supportive periodontal therapy – a cross-sectional study

Purpose Patients with periodontitis, who currently make up a large proportion of the adult population, show high interest in orthodontic therapy. It is therefore important to recognize and assess orthodontic treatment need in these patients. The index of orthodontic treatment (IOTN) is an established tool to determine malocclusions clinically and digitally.Materials and methods A semi-automatic IOTN-assessment using OnyxCeph3TM was performed on patients undergoing supportive periodontal therapy (SPT). Intra- and inter-rater reliability were investigated using intra-class-coefficient (ICC). Self-perceived aesthetic by patients and perception by the investigator according to the aesthetic component (AC) were compared to both each other and normative need, measured by the dental health component (DHC). Periodontitis stage and grade and the possibility of an orthodontic treatment were determined.Results The mean age of the 64 included patients in this study was 62.1 years (SD ± 8.6; min-max 45–81) at the time of the examination. Self-related AC was different to the investigator’s assessment (ICC: = 0.474; 95%-CI: [0.262, 0.643]). Normative treatment need compared to self-perceived treatment need resulted in poor reliability (ICC: = 0.098; 95%-CI: [−0.071, 0.298]). Comparison of IOTN between investigators showed moderate reliability for AC (ICC: = 0.618; 95%-CI: [0.331, 0.799]) and an excellent reliability for DHC (ICC: = 0.932; 95%-CI: [0.863, 0.967]). AC Intra-rater reliability was considered good (ICC: = 0.796; 95%-CI: [0.613, 0.898]). Orthodontic treatment was possible in 48 of the 64 patients.Conclusion Semi-automated IOTN-assessment showed satisfying inter- and intra-rater reliability, but patients’ self-perceived dental aesthetics differed from the dentist’s assessment as well as from the normative treatment need.