title: Comparison of shade matching by visual observation and an intraoral dental colorimeter.
abstract: The purpose of this study was to compare the applicability of two shade-matching approaches: Vintage Halo shade guide (visual method) and Shofu ShadeEye NCC colorimeter (instrumental method). Twenty participants' maxillary left central incisors were evaluated. Corresponding metal ceramic crowns were fabricated with each shade-matching approach. The colour distributions (L*, a* and b*) of the middle third region of each tooth and corresponding metal ceramic crowns were spectrophotometrically assessed. The colour difference (DeltaE) and colour distributions (DeltaL*, Deltaa* and Deltab*) between the tooth and the corresponding crowns were calculated. We found that the colour differences of both groups fell within the clinical unacceptable range (DeltaE > 2.75). Regarding DeltaE and the three colour distributions, no significant difference was found, expect for a* (P < 0.01). The shade matching difficulty degree was analysed through the agreements of visual shade selection. Within easy matching cases, the instrumental method achieved better results (P = 0.041). In conclusion, it is suggested that the reliability of shade matching can be ensured by neither the colorimeter nor the visual approach. However, the colorimeter can achieve better results within easy matching cases.
authors.affiliation: Key Laboratory for Oral Biomedical Engineering of Ministry of Education, School and Hospital of Stomatology, Wuhan University, China.
authors.forename: Q
authors.initials: Q
authors.lastname: Li
authors.forename: Y N
authors.initials: YN
authors.lastname: Wang
mesh_terms: D000328:Adult; D003116:Color; D003118:Color Perception; D003124:Colorimetry; D003442:Crowns; D005260:Female; D006801:Humans; D008297:Male; D017797:Prosthesis Coloring; D013053:Spectrophotometry