Objectives : the aim of this study is to analyze the variation of the color according to the thickness of dental tissues in order to provide a guide for layering the composite in accordance with the preparation depth. Methods : 24 upper central incisors were collected according to the requirements for the study: no conservative/prosthetic restorations or endo-canal treatments. The teeth were cleaned and stored in saline solution. The dental tissues were removed in “dry” condition with ultrasonic air-scaler (SONICflex- amplitude 240μ, frequency 6500Hz) and specific burs that guarantee a preparation parallel to the working plane. The element was prepared starting from the top layer to the pulp; for each preparation 100μ in thickness was removed (T). The surface was polished through a standardized system with high-gloss polishers both passed on the tooth surface for 6 seconds. Using a digital micrometer it was calculated the tooth dental thickness removed. In each preparation the colour difference were spectrophotometrically assessed (SpectroShade™): (DE94) and ΔL*(Lightness), ΔC*(Chroma) and Δh*(hue) from the color space CIELCh. A customized support is realized in order to standardize the measurements (black background, element centered and perpendicular to the axis of measurement). Results : L C μDE94 Central portion T0 L=81.7 T0 C=20.9 5.50(1.2<DE94>10.4) DT1=1365μ L=88.1 DT1=274μ C=22.6 DT2 =2345μ (pulp-chamber) L=78.1 DT2 =2345μ (pulp-chamber) C=9.7 CEJ T0 L=83.2 T0 C=19.9 5.14 (1<DE94>9.4) DT1=1317μ L=89.8 DT1=388μ C=21.5 DT2 =2511μ (pulp-canal) L=84.5 DT2 =2133μ C=12.3 (table 1) We observed that ΔL* and ΔC* are proportional to the thickness removed. In every tooth area we observed a different result and the black-background influence the measurement. Conclusions : The great influence between dental thicknees and dental color carateristics indicate as possible to create a mathematical model that correlates ΔL* and ΔC* to a dental element and resin composite.
Spectrophotometric Evaluation Of The Dental Optical Characteristics According To Thickness
KOVACS VAJNA, Zsolt Miklos;ACQUAVIVA, Pier Antonio;BARABANTI, Nicola;CERUTTI, Antonio
2012-01-01
Abstract
Objectives : the aim of this study is to analyze the variation of the color according to the thickness of dental tissues in order to provide a guide for layering the composite in accordance with the preparation depth. Methods : 24 upper central incisors were collected according to the requirements for the study: no conservative/prosthetic restorations or endo-canal treatments. The teeth were cleaned and stored in saline solution. The dental tissues were removed in “dry” condition with ultrasonic air-scaler (SONICflex- amplitude 240μ, frequency 6500Hz) and specific burs that guarantee a preparation parallel to the working plane. The element was prepared starting from the top layer to the pulp; for each preparation 100μ in thickness was removed (T). The surface was polished through a standardized system with high-gloss polishers both passed on the tooth surface for 6 seconds. Using a digital micrometer it was calculated the tooth dental thickness removed. In each preparation the colour difference were spectrophotometrically assessed (SpectroShade™): (DE94) and ΔL*(Lightness), ΔC*(Chroma) and Δh*(hue) from the color space CIELCh. A customized support is realized in order to standardize the measurements (black background, element centered and perpendicular to the axis of measurement). Results : L C μDE94 Central portion T0 L=81.7 T0 C=20.9 5.50(1.2I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
