کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5433198 | 1398057 | 2016 | 12 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Lightness, chroma and hue differences on visual shade matching Lightness, chroma and hue differences on visual shade matching](/preview/png/5433198.png)
ObjectivesTo analyze the influence of lightness, chroma and hue differences on visual shade matching performed by dental students.Methods100 dental students (DS) volunteers with normal vision participated in the study. A spectroradiometer (SP) was used to measure the spectral reflectance of 4 extracted human upper central incisors (UCI 1-4) and shade tabs from Vita Classical (VC) and Vita Toothguide 3D-Master (3D) shade guides. Measurements were performed over a gray background, inside a viewing booth and under D65 illuminant (diffuse/0° geometry). Color parameters (L*, a*, b*, C* and h°) were calculated. DS used VC and 3D to visually select the best shade match for each UCI. CIE metric differences (Îa*,Îb*,ÎLâ², ÎCâ² and ÎHâ²) and CIEDE2000(2:1:1) lightness (ÎEL), chroma (ÎEC) and hue (ÎEH) differences were obtained from each UCI and the first three shades selected by DS and the first option using CIELAB, CIEDE2000(1:1:1) and CIEDE2000(2:1:1) color difference metrics. The closest CIELAB color-discrimination ellipsoid (from RIT-DuPont visual color-difference data) to each UCI was selected for the analysis of visual shade matching.ResultsDS showed a preference for shades with lower chroma (ÎCâ² and ÎEC) and/or hue (ÎHâ² and ÎEH) values instead of shades with lower lightness values (ÎLâ² and ÎEL). Most best visual matches were near the tolerance ellipsoid centered on tooth shade.SignificanceThis study is an attempt to partially explain the inconsistencies between visual and instrumental shade matching and the limitations of shade guides. Visual shade matching was driven by color differences with lower chroma and hue values.
Journal: Dental Materials - Volume 32, Issue 11, November 2016, Pages 1362-1373