A comparison between visual, digital photography and polarizing filter photography for shade selection

There is an increased awareness for aesthetically pleasing restorations among patients in current practice. Due to variability in the natural tooth colour, shade selection becomes an intricate procedure. The aim of this study is to determine which of the three named methods is more accurate for shade selection in aesthetic dentistry.

Two VITAPAN classical shade guides were used for this study. Nine shades were selected from the first shade guide (A1, A2, A3.5, B1, B2, B3, C1, C2, C3) and the number was concealed. Ten selected participants were asked to identify each concealed shade with the second shade guide. Canon 5D camera with ISO 200, shutter speed 1/100 sec, F22 was used for capturing images of the second shade guide. Photoshop CS3 Software was used for developing the digital shade guide. The participants were asked to match the shades from the first shade guide with the prepared digital shade guide. The third photographic shade guide was prepared using a polarised filter on the Canon 5D camera with the same settings. The participants were asked to match shades with the prepared photographic shade guide.

Total observations made during the study were 270. Cross table statistical analysis (Chi-square test) done using SPSS 20.0 showed statistically significant difference between conventional and digital photography (P = 0.049). Analysis between digital photography and polarizing filter photography did not reveal a significant association (P = 0.181).

Digital photographic method was most accurate among the three shade selection methods. It can be used to obtain aesthetic results.