OBJECTIVES: To assess sustainability of shortened dental arches (SDA) by determining time to 'first restorative intervention' of teeth and time to 'tooth loss' and comparing these outcomes with complete dental arches (CDA) and SDA plus removable dental prostheses (RDP). METHODS: Data (follow-up time ranged from 27.4 (SD 7.1) to 35.0 (SD 5.6) years; max. follow up: 45.8 years) from patient records of 59 subjects (23 SDA, 23 CDA, and 13 SDA plus RDP) participating in a prospective cohort study on shortened dental arches (SDA) were analysed. Group effects on survival were analysed using Cox regression models; where appropriate Kaplan-Meier analyses were done. RESULTS: Compared to SDA subjects, CDA subjects had a lower risk to receive a first restorative intervention in anterior teeth (HR=0.377; 95% CI [0.205-0.695]) and premolars (HR=0.470; 95% CI [0.226-0.977]). CDA subjects had a lower risk to lose premolars compared to SDA subjects (HR=0.130; 95% CI [0.053-0.319]). Risk for 'first restorative intervention' and for 'tooth loss' did not significantly differ between SDA with and without RDP. CONCLUSIONS: SDA subjects had an increased risk to lose premolars and to receive a first time restoration in anterior teeth and premolars compared to CDA subjects. SDA subjects with RDP had no increased risk to receive a first restorative intervention or for tooth loss compared to SDA without RDP. CLINICAL RELEVANCE: Subjects with shortened dental arches can be discerned as enduring at-risk patients. It is therefore recommended that shortened dental arch subjects receive intensive and continuous care to prevent further tooth loss.