Seyed Hadi Sajjadi
Hormozgan Aluminum Corporation, Iran
Title: Effects of three types of digital camera sensors and two camera lenses on dental specialists’ perception of smile esthetics: Two double-blind clinical trials
Biography
Biography: Seyed Hadi Sajjadi
Abstract
Purpose: The effect of image quality or dental specialties on the subjective judgment of facial beauty has not been evaluated in any study. We evaluated the effect of digital sensors, camera lenses and dental specialties on the perception of smile beauty.
Materials & Methods: In the first phase of this double-blind clinical trial, 40 female smile photographs (taken from dental students) were evaluated by a panel of 3 prosthodontists, 6 orthodontists, and 3 specialists in restorative dentistry, to select the most beautiful smiles. In the second phase, the 20 students having the most appealing smiles were again photographed in standard conditions, but this time with three different digital sensors: Full-frame 21.1-megapixel, half-frame 18.0-megapixel and compact 10.4-megapixel. The same was repeated with two different lenses: Regular and then macro lenses. The same panel judged smile beauty on a visual analog scale. The referees were blinded of the type of sensors and the images were all coded. The data were analyzed using two-way ANOVA, Kruskal-Wallis and Mann-Whitney U tests (α=0.05, α=0.0167).
Results: The mean scores for full-frame, half-frame, and compact sensors were 6.70±1.30, 4.56±1.29, and 4.40±1.39 [out of 10], respectively (Kruskal-Wallis P=0.000). The differences between the full-frame with the other sensors were statistically significant (Mann-Whitney P values<0.01). However, the difference between the half-frame and compact sensors was not statistically significant (P>0.1). The scores given by groups of specialists were not statistically different (Kruskal-Wallis P=0.7). Sensors (ANOVA P=0.0000)
but not specialties (P=0.687) affected the perception of beauty. The lenses led to similar scores of beauty perception (Mann–Whitney P=0.8). There was no difference between subjective beauty perception of specialties (Kruskal–Wallis P=0.6). Two-way ANOVA indicated no significant role for lenses (P=0.1750), specialties (P=0.7677), or their interaction (P=0.7852).
Conclusions: The full-frame sensor produced consistently better results and was recommended over half-frame and compact sensors. The photographs taken by a regular lens and then digitally magnified can be as appealing as close-up photographs taken by a macro lens. Dentists of different specialties might have similar standards of smile beauty, although this needs further assessment.