Temporary Crown Clinical Performance in a Practice-based Research Network (PROH)

Objectives: The purpose of this study was to evaluate the performance of a new temporary crown (Protemp/3M ESPE), in 101 crown prepared teeth in the permanent dentition of adult patients.

Methods: Ten members of the PROH practice-based research network each placed 10 Protemp temporary crowns while fabricating crowns on 101 permanent posterior teeth using standardized preparation/luting criteria. Baseline (tooth preparation appointment) and recall (permanent crown cementation appointment 2-4 weeks later) assessments were completed for each temporary crown using modified Ryge criteria. Additionally, practitioners rated wear, bruxism, temperature and biting sensitivity (VAS). Changes from baseline to the recall appointment were analysed using McNemar's test for binary outcomes and the paired t-test for quantitative outcomes. Associations between measures were assessed using logistic regression and generalized estimating equations. A 0.05 level of statistical significance was used for all analyses.

Results: The overall retention rate of the temporary crowns was 87%, and the overall fracture rate was 11%. Patients identified as bruxers exhibited significantly greater wear than non-bruxers. There were significant changes between baseline and recall measures in temperature and biting sensitivity (VAS), and gingival index but the changes into a better level were statistically balanced by changes to a worse level. There were no significant differences in occurrence of baseline/recall temperature sensitivity or biting sensitivity, nor was there a significant change in anatomic form from baseline to recall. Practitioners noted that a few temporary crowns demonstrated a marked color change.

Conclusion: In general, Protemp crowns performed satisfactorily as an interim restoration. Supported by 3M-ESPE.