Randomized trial investigating zirconia electroplated telescopic retainers: quality of life outcomes

Abstract

The study aims to evaluate the effect of electroplated telescopic removable dental prostheses (E-RDPs) with zirconia primary crowns on oral-health-related quality of life (OHRQoL). For E-RDPs, electroplating is used to produce precisely fitting gold copings on telescopic primary crowns. These copings are bonded intra-orally to the denture framework. Fifty-six participants in need of 60 removable restorations were randomly allocated one of two materials for the primary crowns: cobalt-chromium alloy or zirconia. OHRQoL was assessed by use of the 49-item Oral Health Impact Profile (OHIP-49) and by additional patient self-rating at baseline before treatment, and after 6 and 12months. Statistical analysis was performed by use of one- and two-sample t-tests and analysis of covariance. Mean OHIP sum score at baseline was 53.4 (SD 37.4, 95% CI 41.3-62). At follow-ups, it decreased significantly (after 6months: mean 20, SD 26, 95% CI 13-27.1; after 12months: mean 16.4, SD 17.9, 95% CI 11.6-21.2). The mean reduction in OHIP sum score after 12months was 25 (SD 31.2, 95% CI 13.1-36.9) for cobalt-chromium alloy and 44.4 (SD 32.3, 95% CI 31.1-57.8) for zirconia. However, no statistically significant difference of the two materials on OHIP change or patient self-rating was detected. Although OHRQoL was improved by using both cobalt-chromium alloy and zirconia primary crowns for E-RDPs, post-treatment differences between the groups were not statistically significant. Zirconia E-RDPs enhance OHRQoL. However, zirconia primary crowns do not outperform cobalt-chromium alloy crowns regarding patient satisfaction-despite their tooth-like color.