Monday, October 29, 2012
Matching restorations to natural dentition in the anterior esthetic zone is one of the most difficult challenges faced by lab technicians and the dentists they work with.
The simplest route is to shorten the line of communication and let the lab technician take the shade. At Ziemek Laboratories, the majority of shade matching for anterior restorations is accomplished by seeing the patient in the lab for a custom shade photo appointment. The patient is seen by one of the technicians who is actually fabricating the restorations, photos are taken, and a consultation about their expectation of shade matching takes place. Most times a patient simply wants to be done with the restorative process and has realistic expectations of the esthetic outcome, especially if they are replacing a lost or missing tooth with an implant and have had months of waiting for Osseointegration. This can make the custom shade matching process a straight forward and simple procedure, barring the extremely difficult shade matches or the extremely difficult patients (you know who they are).
Keeping patients comfortable
It can be important for patients to be given a chance to voice their expectations and concerns outside of the clinical setting. They may tell the technician something slightly different of even contrary to what they have told their dentist. A fairly common example of this is when we ask a patient if they are bleaching their teeth currently, and if so, when the last time they bleached was so we can make sure enough time has passed to accurately match the shade of the restoration to the bleached natural dentition.
Their dentist most likely told them to stop bleaching a few days to a week prior to their custom shade appointment, but you would be surprised how many patients will tell us that they just bleached hours ago, thinking more and lighter is better. We have even had patients bleach AFTER we see them for a shade appointment and then be completely shocked and displeased when the restoration we fabricate is too dark or has too much chroma!
Staying in touch
In my articles and lectures, you’ll notice that I talk a lot about communication between the dentist and lab, and this is one example of how and when this becomes so important. Any concerns or expectations voiced by the patient at Ziemek Laboratories that raise a red flag are immediately shared with the patient’s dentist so they are 100% in the loop and can make sure the patient is clear about the restorative material selected and has a realistic expectation of the outcome.
I said earlier that the majority of shade matched anterior cases are accomplished by seeing the patient for photos in our lab. This removes the dentist from the position of selecting the shade and puts the responsibility squarely on us. Another possible scenario for shade selection is the dentist selects the shade and simply writes it on the Rx form. In this scenario, the lab is removed from shade selection and thus removed from any responsibility of shade matching, other than making sure the restoration matches the shade tab the dentist selected. This example works well when the patient has a fairly simple shade and value that matches a tab on either the VITA Classic or 3D shade guide.
Communicating with photos
A more complex scenario occurs when the lab and dentist are not located in close proximity to each other, and the distance is too great for the patient to travel to the lab for a custom shade, yet the shade is not simple and does not match a shade tab exactly or the natural teeth have characterization that needs to be replicated in the restorations. The only way to accurately transmit the shade and characterization of challenging natural dentition in this scenario is a digital photograph taken by the dentist or staff and then sent to the lab.
At my lab we have a few dentists who send us cases and shade photos this way (even from the opposite coast) and to be quite honest, it can be difficult to obtain consistent shade results without being able to actually see and photograph the patient in our lab. This is due to a few factors, the most notable being lighting differences and inconsistencies, different cameras and camera settings, different photographers and angles of shade tabs, and general lack of experience from dental offices taking these types of photos.
We experience the most success with custom shade acquisition and matching from digital photographs by being up front with the dentists and their staff, explaining the limitations of this process, and letting them know that when working this way we will not be able to match restorations to natural dentition 100% correctly for every case every time. The dentist or staff member responsible for shade acquisition needs to select the shade tabs that most closely match the natural dentition, photograph them correctly, and then select the final desired shade to the best of their ability, sending the photos to the lab for reference and characterization only.
This scenario is a shared responsibility of shade matching as our lab is not taking the photos or seeing the patient, but is working to the best of our ability from the photos provided by the office. Can we usually get very close? Absolutely. Most of the time the result is a success. But most lab technicians will admit that even with an in-lab custom shade appointment, the most challenging cases sometimes require a custom tint before the final crown seating to get the shade matching exactly.
Tips for shade success
Below are some tips for success when dentists or staff are photographing patients and sending the photos to the lab for shade matching natural dentition in the anterior esthetic zone.
- Have the lab assist the dentist in camera selection. Ask what camera the lab is using to successfully acquire their custom shade photos. It helps if the dentist can purchase the exact same set up for use in the office.
- Make sure the dental practice (or at least the room in which the photos will be taken) has color-correct lighting. If need be, have the lab assist in locating a lighting store in the area that can provide the correct bulbs, etc.
- Ask the lab to provide some examples of both good and bad shade photos with an explanation of what makes them good and bad. It’s a good idea to make this line of communication an ongoing one, so the results can be fine tuned.
- If sending the photos via email is difficult because of the large file sizes, ask the lab to set up an easier online file-sharing system such as a shared cloud drive.
- Be sure to talk to your lab about your shade concerns. In turn your lab should be very honest and straight forward about shade matching expectations when working this way. Patients should also be informed of how the process might play out.
It’s ideal for the technician fabrication the restoration to select the shade, but when it’s not possible make sure the lines of communication are open between both the dentist and lab and the dentist and patient in case the completed restorations need to be sent back to the lab after try in for tinting before a 100% match is achieved.