Instrumental Colour Measurement of Porcelain Laminate Veneers: An In-Vitro Study

Taylor, William Grant (1999) Instrumental Colour Measurement of Porcelain Laminate Veneers: An In-Vitro Study. MSc(R) thesis, University of Glasgow.

Abstract

The choice of shade of tooth coloured restorative materials is very subjective as no quantitative measurement of colour is taken. This can have an effect on the aesthetic success of porcelain laminate veneer restorations, as these are prescribed widely to alter the colour of one or more of the patient's discoloured teeth, to match that of the patient's adjacent teeth. It is therefore extremely difficult for the operator to know which shade to select for the restoration, and in an attempt to alleviate this problem, research has been carried out on the instrumental colour measurement of natural teeth and aesthetic restorative materials to give objective results. The instruments best suited for colour measurement are spectrophotometers and colorimeters. The aims of this study were to establish if the Spectramatch GT spectrophotometer was a suitable instrument for use in the detection of colour differences among porcelain laminate veneers. This study also undertook to determine the effect of various try-in media on the colour of porcelain laminate veneers and to establish the effect of various porcelain laminate veneers on the colour of underlying tabs of various shades used to simulate the crowns of teeth. Shofu Vintage Body Porcelain was used to fabricate 0.5x12mm discs representing laminate veneers and 2.5x12mm base tabs representing the teeth. Four try-in media (air, distilled water, glycerine & base/try-in paste) were used between the veneers and base tabs. The Spectramatch GT spectrophotometer was used to analyse the colour of the samples, with the data recorded in C.I.E. L*a*b* notation, and the C.I.E. DeltaE colour differences calculated. The results showed that the Spectramatch GT spectrophotometer was capable of detecting small colour differences between shades, that there were statistically significant differences between air and all three other try-in media, and that shade A3 & B1 veneers were not capable of producing clinically acceptable shade matches when placed over different shades of base tabs, while shade B4 & C4 veneers were of producing clinically acceptable shade matches when placed over different shades of base tabs.

• Item Type: Thesis (MSc(R))
• Qualification Level: Masters
• Additional Information: Adviser: William P Saunders
• Keywords: Dentistry
• Date of Award: 1999
• Depositing User: Enlighten Team
• Unique ID: glathesis:1999-76397
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 19 Nov 2019 14:44
• Last Modified: 19 Nov 2019 14:44
• URI: https://theses.gla.ac.uk/id/eprint/76397