cosmetic dentistry_ beauty & science

I 11 special topic _ shade analysis I cosmeticdentistry 1_2012 image and the colours will be rebal- anced if there is a colour bias. This will be applied to all the images selected. Photoshopisanidealtooltoisolate (select out) the shade guides and the teeth to be matched from their surrounding backgrounds and then neutralise the backgrounds (Fig. 17). The reader is directed to the detailed technique to do this that has been previously published.18 _Integrating computerised shade-analysis devices The third and equally important aspect of my shade-takingtechniqueisusingcomputerisedshade- taking technology. Computers, the Internet and all digitaltechnologiespermeateeveryareaofdailylife, and dentistry is no different. Several digital shade- analysis technologies have been introduced to den- tistry. Today, we would not be able to work without one of the digital shade-analysis systems but the systems have not evolved to the point that they can replace human perception. It would not be useful in an article of this type to go into the science and technology aspects of the various systems, rather it wouldbeusefultotellyouthepracticalapplicationin state-of-the-artshadeanalysisandcommunication. The computerised systems we tested in-house take a better base shade than the average human shade taker, but humans can detect the subtle variances of tooth colour better. So by experience, we believe the computers can be used to take base shades, then along with visual perception and high qualitydigitalphotography,thethreeusedtogether will give accurate shade information to be used by the ceramist. I take my visual shade before taking a computerisedshadesothatitdoesnotbiasmyper- ception. We have several systems at UCLA (Univer- sity of California, Los Angeles), the VITA Easyshade (Vident), Shade-X and Shade-Rite (both X-Rite), and the Crystal Eye (Minolta), and there are several others on the market. All of them work to a certain extent. We believe from experience that a device should be simple and give an accurate base shade. Easyshade (Fig. 18) in our tests is the easiest to use for base shade and has been proven to provide as or more accurate base shade than the average visual shade taken by a group of dentists. If photographs are not taken (which is not recommended), the Crystal Eye also gives good shade information and a digital image, but the system is much more ex- pensive. Figures 19 and 20 are before and after im- ages of a single central incisor fabricated using this technique. _Summary A three-part system for shade analysis and communication has been detailed in this paper. All three parts are interdependent and when used in concert have reduced remakes for shade mis- matches in the UCLA’s Center for Esthetic Dentistry clinic by more than 80 %._ Editorial note: A complete list of references is available fromthepublisher. Fig. 19_Pre-op image of a crown of which the patient complained that the restoration was too low in value. Fig. 20_Post-op image of a single central incisor using VM 13 (Vident). Prof Edward A.McLaren maintains a private practice limited to prosthodontics and aesthetic dentistry.He is Director of the UCLA Center for Esthetic Dentistry,which offers a full-time didactic and clinical programme for graduate dentists.He is also the founder and Director of the UCLA School for Esthetic Dental Design. Prof McLaren is a member of theAmerican College of Prosthodontists,Pacific Coast Society for Prosthodontists,International College of Prosthodontists,AmericanAcademy of Esthetic Dentistry,International Society of Dental Ceramics, InternationalAssociation for Dental Research, AmericanAssociation for Dental Research,American DentalAssociation and California DentalAssociation. He is actively involved in many areas of prosthodontic and materials research and has published several articles.He conducts ongoing clinical research on various restorative systems.He has presented numerous lectures,hands-on clinics and postgraduate courses on ceramics and aesthetics. Prof Edward A.McLaren UCLA Continuing Dental Education Box 951668,RoomA0-121 CHS LosAngeles,CA,USA _about the author cosmeticdentistry Fig. 20Fig. 19