Effect of background color on color measurement
MetadataShow full item record
Statement of the problem: When evaluating tooth shades many elements such as background can affect the color interpretation. Spectrophotometers have been developed to perform detailed shade analysis with the goal of reducing or eliminating extrinsic factors that can affect the human eye and result in color evaluation errors. However the oral cavity is generally a red environment; it would be very valuable to understand how variations in background colors and different shades of red backgrounds could affect interpretation of a shade by a spectrophotometer. Objective: 1.To analyze the effect of different background colors on tooth color as measured by spectrophotometer. 2.Determine the optimum background color for color measurements by spectrophotometer. 3.Determine which specific tooth shades are more susceptible to background color change as measured by spectrophotometer. Materials and methods: Four shade tabs from Vita classical shade guides A2, B2, C2 and D2 were selected. Five background colors were selected; Pink, Magenta and Red were selected to simulate gingival tissue variations. Black was chosen because it's the most used background color in intra-oral photography. Gray was selected as a neutral color to minimize visual effects and to act as a reference point. Each sample of Vita Classical shade Tab was exposed to Spectrophotometric measurements by Spectro-Shade Micro on each background color 15 different times. Tooth color was expressed according to Vita Classic Shade guide (A1, B2, etc.) [Delta]E (color difference) between the chosen tabs and the reference were calculated. [Delta]E were compared and two ways analysis of variance (ANOVA) test with replication was performed. Statistical evaluation measured the effects of two factors: background color and shade tab color simultaneously. Results: Effect of background: Gray background provoked the least increase in [Delta]E values. Red background provoked the largest increase in [Delta]E values. Effect of Shade Tab: [Delta]E value increased more in Shade Tabs B2 and A2 with a smaller increase for C2 and D2. Conclusions: 1) Background color exhibited a significant effect on color measurements by the dental spectrophotometer tested (P= 0.0000). 2) There was a significant difference on the background effect over color measurement when background color changed from Gray to pink (P= 0.00001) and Black to Red (P= 0.00001). 3) There was no significant difference on the background effect over color measurement when background color was changed from Gray to Black (P=0.0 1 7). 4) B2 Shade tab was the most sensitive shade Tab to background change (P=0.0000). 5) C2 Shade Tab showed least sensitivity to Background color change (P=0.0000).
PLEASE NOTE: This work is protected by copyright. Downloading is restricted to the BU community: please click Download and log in with a valid BU account to access. If you are the author of this work and would like to make it publicly available, please contact email@example.com.Thesis (MSD) --Boston University, Henry M. Goldman School of Dental Medicine, 2012 (Department of Restorative Sciences and Biomaterials).Includes bibliographic references: leaves 61-63.
RightsThis work is protected by copyright. Downloading is restricted to the BU community. If you are the author of this work and would like to make it publicly available, please contact firstname.lastname@example.org.