title: Developing a custom dental porcelain shade system for computer color matching.
abstract: OBJECTIVE
  This study aims to update the computer color matching method by generating a new ceramic shade system that covers the entire spectrum of natural tooth color and has an efficient design.
  
  
  METHODS
  First, the color map of 176 maxillary natural incisors and two commercially available and commonly used shade guide systems (Vitapan classic and 3D master) were drawn. Then, 15 shades of layered disks (NW-0: neutral white-0, A1, A2, A3, A4, B1, B4, C4, and D4, and six modifiers; white, pink, grey, blue, cervical-1 and cervical-2, Cerabien ZR) were plotted on the tooth color distribution map. Ultimately, 12 target shades were selected around the perimeter of the natural tooth color space, and nine different shades were selected within the cluster. By trial and error informed by known formulations published previously, the formulations of Cerabien ZR porcelain powders necessary to achieve these 21 target shades in thickness of 1.0mm layered on zirconia substrate were then determined and ceramic disks were fabricated.
  
  
  RESULTS
  Color distribution L*-C* and a*-b* maps showed that new 21 shade system covers a slightly broader range than the natural tooth distribution, and its distribution is larger than the 3D Master shade's range.
  
  
  CONCLUSIONS
  In the present study, a 21 custom dental porcelain shade system was developed with a 1.0mm porcelain thickness overlying a zirconia substrate, which can be incorporated into the computer color matching system. This new shade system has homogeneity with 3D Master, and has a slightly wider color distribution than that of natural teeth.
authors: Department of Restorative Dentistry and Biomaterials Sciences, Harvard School of Dental Medicine, Boston, MA, United States.
authors: Shigemi
authors: S
authors: Ishikawa-Nagai
authors: Jian
authors: J
authors: Wang
authors: Alison
authors: A
authors: Seliger
authors: Jin
authors: J
authors: Lin
authors: John
authors: J
authors: Da Silva
mesh_terms: D003116:Color; D017076:Computer-Aided Design; D019992:Databases as Topic; D003764:Dental Materials / Q000737:chemistry; D003776:Dental Porcelain / Q000737:chemistry*; D017267:Dental Prosthesis Design / Q000295:instrumentation; D003804:Dentin / Q000033:anatomy & histology; D007180:Incisor / Q000033:anatomy & histology; D017797:Prosthesis Coloring / Q000295:instrumentation* / Q000592:standards; D012984:Software; D013053:Spectrophotometry / Q000295:instrumentation; D014073:Tooth Bleaching; D015040:Zirconium / Q000737:chemistry
chemical_list: D003764:Dental Materials; D003776:Dental Porcelain; D015040:Zirconium; C028541:zirconium oxide
keywords: Computer color match; Dental porcelain; Shade