The fundamental element of cosmetic dentistry is ability to match color of restoration to mimic adjacent natural teeth. This entails consideration of many factors , especially most important of them are three s - Chroma, Hue, Value.
Value best addressed in Black and White view. Complex shade matching for lateral incisors. Central were addressed with multi shaded bonded resin. Note the discrepancy in the value of laterals.
Here are my three common important steps for every single cosmetic cases which I undertake. First and foremost is to analyze the existing tooth substructure for - degree of opacity , translucency,and transparency. Here I am factoring enamel thickness and underlying dentin, to determine final shade and suitable material selection.
Second factor is to consider type of ceramic material to be used to restore the tooth. Material selection is different for each clinical case. There is room for all the materials currently available , most dentist consider material towards strength. In my opinion with accurate communication with the dental lab technician and providing all the relevant data - dentist will be able to produce a rewarding results for your patient.
Pre-op photo of the clinical case is important - take them in upright seated position with retractors and a dental modified DSLR camera. Document pre existing shade using shade guide such as vita or vita3d master. Once tooth is prepped - take stump shade for lab purpose-, also document depth cut used for the case. If you are prepping tooth 1mm to 1.2mm facial prep - ceramist can mask any underlying color. Once temporary crown is cemented final photos are taken - here I use vita shade tab with a grey tab background - important is to make sure your Lab tech is also using the similar grey tab. We upload all the images to free software from Google - Picasa- for storing and sharing purpose. You can also convert images to black and white to reveal grey value. Of the all the elements it is the "Value" which is most important to match the exact shade. Value is also expressed in terms of brightness( high or low). Note translucency adds greyness to the teeth, so limits the use and change to iridescent blue shade.
Few common thought process for anterior teeth shade matching. Always perform the procedure in morning or natural light. This will remove most error in color selection for single tooth shade matching. Also modify the color in the clinical setting to minimum 4800k temperature , most available in the market is 1200 to 1800. My practice have lighting adjusted for this purpose. If you cannot take the shade in natural light, check with your ceramist when they take shade and what method they prefer. Also one aspect is to send the patient to the dental lab for custom shade by ceramist. Single tooth is best addressed for custom shade by ceramist.
Datta Malyavantham DDS BDS