Dental shade assessment via various digital photograph parameters: A pilot study

OBJECTIVES: Accurate shade matching is essential for successful restorative and prosthodontic dental treatments. Various methods, including visual, digital, and spectrophotometric techniques, have been utilized for shade selection. However, there is limited data regarding the optimal photographic parameters that yield the most accurate shade matching in digital photography. This pilot study aims to evaluate color differences arising from variations in photographic parameters -specifically camera aperture and ISO-while maintaining a constant shutter speed of 1/125. MATERIALS-METHODS: Spectrophotometric shade analysis (VITA Easyshade) was performed ten times on the maxillary right central incisor of a subject and the A1 tab from the VITA Classical shade guide before photography. A total of 12 digital images were captured using a DSLR camera (Canon EOS 850D) equipped with a 100 mm macro lens and ring flash (without polarized filter). The photographic parameters included a constant shutter speed (1/125 s), varying aperture values (f/11, f/13,f/22, f/32), and ISO values (100,160,200). Colorimetric evaluations were conducted using Adobe Photoshop, analyzing CIE Lab* coordinates and calculating ΔE values. RESULTS: The lowest ∆E value was recorded with ISO 200, f/32 aperture, and 1/125 shutter speed in the tooth group (5.41 ± 1.92), while the highest ∆E value was obtained with ISO 100, f/11 aperture, and 1/250 shutter speed in the shade guide group (62.14 ± 3.90). The digital photographic ∆E values mostly remained within the clinically unacceptable threshold (ΔE > 2.7 and ≤ 5.4). CONCLUSION: Within the limitations of this pilot study, digital photography alone for shade selection remains inconclusive.Further studies are warranted to comprehensively compare shade-matching accuracy using digital photography.