IMPACT OF SHORTENED DENTAL ARCH ON ORAL HEALTH-RELATED QUALITY OF LIFE

Background A shortened dental arch (SDA) is an established treatment concept for patients with missing molars. However, little is known regarding long-term course of oral health-related quality of life (OHRQoL) in patients with SDA and the benefits from replacement of missing molars. Aim Purpose of this multi-center randomized clinical trial was to assess OHRQoL over a period of 15 years in patients with molar replacement by a removable partial denture (RPD) compared to patients with a restored SDA without molar replacement. Design Patients at least 35 years of age with all molars missing in one jaw and at least the canine and one premolar present on each side were included. Patients received either a precision attachment-retained, RPD for replacement of missing molars (N=79), or the dental arch ended with the second premolar (SDA) that had to be present or replaced by a cantilever fixed dental prosthesis (N=71). Follow-up examinations continued for 15 years. OHRQoL was assessed with the 49-item Oral Health Impact Profile (OHIP). OHIP summary and dimension scores were longitudinally modeled in the statistical analyses to assess course of OHRQoL over time applying an intention-to-treat approach. In addition, scores for the OHRQoL dimensions Oral Function, Orofacial Pain, Orofacial Appearance, and Psychosocial Impact were analyzed. Results After an initial improvement in OHRQoL indicated by a mean decrease of 20.0 OHIP points with an effect size of 0.61 in the entire study population, OHRQoL stayed relatively constant over the entire follow-up period. Assuming a constant time and treatment effects over the study period, OHRQoL did not differ statistically significant between the two treatments (0.4 OHIP points; 95%-CI: −7.1 to 6.2). OHRQoL after treatment did not change notably over 15 years and was statistically nonsignificant as well (p=0.872). Similar findings were observed in all four OHRQoL dimensions. Conclusions In patients, missing all molars in one jaw OHRQoL improved providing RPD or restoring SDA to a clinically relevant degree. Treatment-related improvement remained mostly stable over a period of at least 15 years. Therefore, patients can be informed that both treatment concepts are equivalent concerning long-term OHRQoL. Accordingly, patients’ preferences regarding treatment options should be granted priority in treatment decision making with the SDA treatment option being the default.