Differences in Lip Support with and without Labial Flanges in a Maxillary Edentulous Population. Part 4:...

To study the subjective differences in facial esthetics evaluations and the ability to distinguish facial changes due to changes in lip support, when evaluated by patients themselves. An additional objective was to study the differences between patients' self-evaluation versus evaluation of other patients.

A total of 22 maxillary edentulous patients from the original sample of 31 patients described in Part 1 of the study, returned to participate in this part of the study. The 22 patients acted as judges for all images in this study, and were therefore un-blinded to the objectives and details of the study. Patients first completed evaluation of facial esthetics on a visual analog scale (VAS). Four digital images per patient (total of 88 images) were evaluated in a random order, twice by all 22 patients. The mean scores from all judgments were used as the outcomes to be analyzed. All patients then took a discriminatory sensory analysis test (triangle test) where they were required to correctly identify the image with a flangeless denture out of a set of 3 images. Both the VAS and triangle test ratings were conducted twice in a random order, and mean ratings were used for all analyses.

For VAS analysis, there were no statistically significant or clinically significant differences in facial esthetics ratings between flange and flangeless dentures (p < 0.05). This was true for both profile and frontal images, irrespective of self-evaluation versus evaluation of other patients, years of patient edentulism, and judge (patient) gender. For the triangle test, frontal images had a correct identification rate of 50.2% and profile images of 50.4%, and the difference was not significant. There were no significant differences in triangle test results with respect to self-evaluation versus evaluation of other patients and judge (patient) gender. For all patients, the likelihood of correctly identifying images with flangeless dentures was significantly greater than 1/3, which was the minimum chance for correct identification (p < 0.0001).

Flangeless dentures resulted in no differences in facial esthetics ratings for frontal and profile images, when evaluated by patients. When patients were forced to look for differences, flangeless dentures were detected in half of the image sets. These findings were similar for self-evaluation versus evaluation of other patients and for both patient genders.