Predictors of survival of large non-occlusal non-incisal glass-ionomer restorations in older adults

Purpose: This study aimed to investigate the predictors of survival of non-occlusal non-incisal glass-ionomer restorations as a surrogate for root surface restorations among older adults. Methods: In a retrospective cohort analysis using the University of Iowa College of Dentistry electronic dental records, we included 721 patients aged 65+whoreceived 2+surface non-occlusal non-incisal glass ionomer restorations placed from January 2005 - December 2011. Restorations were followed until September2017 or until they were deemed to have failed. Results: At baseline, participants' mean age was 77.6 +/- 8.2 years, and 45.8%were females. Most patients were self-pay (65.2%). Most restorations were placed by residents and dental students (82.7%) and included only two surfaces (95.6%).About half (49.1%) failed during follow-up, with a median survival time of3.7 years. The time ratio for lower incisors compared to other teeth was 0.6(p=.006), for three-and-four-surface restorations compared to two was 0.7(p=.007), for faculty as providers compared to residents and students was 1.4(p=.039), and for the Geriatric & Special Needs Clinic compared to others was 0.8 (p=.013). Time ratios less than one indicate association with shorter durations for restorations, and time ratios greater than one indicate association with longer durations for restorations. Conclusion: Tooth type, number of restored surfaces, provider type, and clinic were all significant factors associated with survival of these restorations.