Evaluating the Validity of the Pink Esthetic Score

Objectives: There is a need for an objective system to evaluate esthetics of the peri-implant soft tissue.  The Pink Esthetic Score (PES), proposed by Furhauser et al., is one metric although it relies on a subjective ordinal set of scales. The goal of this study is to develop calibrated examiners who can have a higher agreement than 70.5% as reported by Gehrke et al in 2008 using the PES.

Methods: Five dentistry faculty used the PES to evaluate 10 digital photographs using the PES variables: mesial papilla, distal papilla, soft tissue level, soft tissue contour, soft tissue color, soft tissue texture, and the alveolar process. The participants rated the tooth in question using a 0 (poor), 1 (acceptable), 2 (best) ordinal scale to evaluate the PES variables compared with the contralateral tooth.  Participants were than retested two weeks later.  Eight additional dentists of different specialties were also given the survey to test differences between specialties (total 13 subjects).  Qualtrics a secure, online data collection service was used for the survey.

Results: 94% of the images were graded within 6 points of each other.  The median difference for a given participant ranged from 0.5 to 2.5 points.  The participants showed an inter-rater agreement of 0.53 which is modest level of agreement and highly significant (p< 0.0001).  Orthodontist had the lowest agreement (0.48) and dental students showed the highest agreement (0.77) based on Kendall's Concordance. 

Conclusions: A web-based survey can be used for measurement of implant esthetics.  Based on the results of this study the ordinal scale used to assess the soft tissue esthetics surrounding a single tooth implant is highly variable.  Calibration training prior to conducting the survey is critical but scoring drift still occurred.  Support: Astra Tech AB.