Objectives
The aim of the study was to evaluate the responsiveness of the Prosthetic Esthetic Index (PEI) in a population who received prosthetic replacements.

Materials and methods
Fifty-seven patients who received prosthetic replacement of at least one tooth by means of fixed or removable prosthesis were professionally esthetically evaluated using the PEI and the Dental Aesthetic Index (DAI) before and after treatment. The participants further evaluated their oral esthetics using the Oral Health Impact Profile Aesthetic (OHIP-Aes) and Orofacial Esthetic Index (OES). Responsiveness was determined by calculating effect size (ES) and standardized response mean (SRM) of the change in PEI score, testing the change in PEI score in different subgroups, and correlating the change in PEI score with the change in OHIP-Aes and OES scores. The change in PEI score was compared to the change in DAI score.

Results
The ES and SRM were large for the change in PEI score. Patients having anterior teeth replaced had a larger improvement in PEI score compared to participants not having anterior teeth replaced. The change in PEI score was moderately but significantly correlated to the change in OHIP-Aes and OES scores. The PEI was more consistent in responsiveness than the DAI.

Conclusions
The PEI shows sufficient responsiveness for use in longitudinal studies and for use as a follow-up measure in clinical practice.

Clinical relevance
The PEI can in a standardized manner monitor and document esthetic improvements and problems as seen by the dentist in clinical practice.