Objectives: Oral health-related quality of life (OHRQoL) is a multifaceted field involving many factors. The aim of our study was to assess whether implant therapy improves OHRQoL in dental patients.
Methods: Patients receiving at least one implant completed a health-related questionnaire before and after the implantation (minimum 1.5 months). Questions covered the functional and aesthetic scales (AS). Paired differences in individual scores were analysed using the Wilcoxon signed-rank test. A univariate analysis of covariance was used to relate overall and scale-specific average paired differences to age, gender, marital and educational status. Multivariate analysis of covariance was used to assess interactions between the covariates and different scales of outcome. All tests were performed at statistical significance level α = 0.05.
Results: All twelve Wilcoxon tests supported an improvement in OHRQoL after implant placement. On the AS, the mean difference in OHRQoL scores was found to be associated with marital status, presence of aesthetic reasons for undergoing the surgery and number of front teeth replaced by implants. On the functional scale (FS), most significant associations were observed with the number of front teeth replaced via implantation, followed by the presence of chewing problems and marital status. The multivariate analysis helped to identify the covariates that varied significantly over the two scales of interest.
Conclusions: Effects of covariates responding significantly differently on different scales should not be summarized using an overall univariate analysis, using paired score differences averaged over all items. Such effect summary would be misleading. In the present study, significant implant-related improvements in OHRQoL were observed on both the aesthetic and FS in patients with at least one implant in the front dental area.
© 2012 John Wiley & Sons A/S.