Shade matching

Dental Devices Shade matching Background.—Esthetic dental procedures are growing in popularity, spurring on the search for a reliable color replication process. Shade guides have two potential sources of error: first, by the dentist in selecting the shade and, second, by the ceramist in replicating it. In addition, the available shade guide may not include the specific hue, value, and chroma of the tooth. Natural teeth have characteristics that complicate the selection of a matching shade. Surface texture, translucency, color of the surrounding environment, and the combined effect of enamel translucency plus dentin opacity are among the factors that make choosing a color difficult. Electronic systems have been developed to objectify the process and make it more accurate. The reliability and accuracy of four dental electronic shade-matching devices were assessed. Methods.—The shade-matching devices tested were the SpectroShade, ShadeVision, VITA Easyshade, and ShadeScan (Table 1). Three shade guides (Vitapan Classical, Vitapan 3D-Master, and Chromascop) were measured, then shade tabs were placed in the middle of a gingival matrix. The shade tabs of the same shade from other shade guides were placed on either side. For reliability, 10 electronic measurements from each of the three shade guide types were obtained from the middle region of the shade tab within a black box. To measure accuracy, each shade tab from the 10 guides of the three types was assessed once. The differences in reliability and accuracy were evaluated statistically.

Table 1.—Devices Evaluated Device

SpectroShade

ShadeVision VITA Easyshade ShadeScan

Manufacturer

Type

MHT Optic Research AG, Niederhasli, Switzerland X-Rite America, Inc, Grand Rapids, Mich Vident, Brea, Calif Cynovad, Montreal, Canada

spectrophotometer

digital camera with colorimeter spectrophotometer digital camera with colorimeter

(Courtesy of Kim-Pusateri S, Brewer JD, Davis EL, et al: Reliability and accuracy of four dental shade-matching devices. J Prosthet Dent 101:193-199, 2009.)

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Dental Abstracts

Table 2.—Reliability and Accuracy Data (%) Shade-matching Device

SpectroShade ShadeVision VITA Easyshade ShadeScan

Reliability (SD)

Accuracy (SD)

96.9 (0.69) 99.0 (0.40) 96.4 (0.75) 87.4 (1.33)

80.2 (15.59) 84.8 (1.44) 92.6 (1.05) 66.8 (1.89)

(Courtesy of Kim-Pusateri S, Brewer JD, Davis EL, et al: Reliability and accuracy of four dental shade-matching devices. J Prosthet Dent 101:193-199, 2009.)

Results.—ShadeVision had a reliability of 99.0%, followed by SpectroShade at 96.9%, VITA Easyshade at 96.4%, and ShadeScan at 87.4% (Table 2). The difference between the most and least reliable devices was significant. The accuracy of the devices was greatest for VITA Easyshade at 92.6%, then ShadeVision at 84.8%, SpectroShade at 80.2%, and ShadeScan at 66.8%. The differences were statistically significant for all devices except between SpectroShade and ShadeVision. Discussion.—The reliability of the devices tested was similar and quite high, with none of the devices scoring less than 96%. However, accuracy varied from 66% to 93%. Only the VITA EasyShade device had reliability and accuracy scores over 90%.

Clinical Significance.—We need to be able to consistently and accurately measure tooth color so we can achieve the best result for our patients. Restorations should look as natural as possible. Using electronic devices, we can achieve good reliability, but the accuracy remains to be improved for most devices. The test used here may help in choosing a device that works for you.

Kim-Pusateri S, Brewer JD, Davis EL, et al: Reliability and accuracy of four dental shade-matching devices. J Prosthet Dent 101:193-199, 2009 Reprints available from S Kim-Pusateri, State Univ of York at Buffalo, Dept of Restorative Dentistry, School of Dental Medicine, 3435 Main St, Squire Hall, Rm 222, Buffalo, NY 14214; fax: 716-8292440; e-mail: [email protected]