When Words Are Not Enough
Inside Dental Technology delivers updates on digital workflows, materials, lab techniques, and innovation in dental technology through expert articles and videos.
Adamo E. Notarantonio, DDS; and Amanda Seay, DDS
To consistently achieve excellent functional, esthetic, and biologic outcomes, the design of dental restorations should occur very early during treatment planning. When more information is shared between the clinician and the laboratory, a case can proceed more smoothly as it moves through preparation and provisionalization to the final restorations. Historically, laboratory technicians have selected the tooth shapes and arrangement based on guidelines provided by dentists through written prescriptions or phone conversations. This process left the laboratory technician unable to catch errors in clinical record taking or to see the dynamic facial movements of the patient whose smile he or she was creating. Even if a clinician fully adopts the process of digital smile design, a digital camera remains the most critical instrument for simplifying documentation and strengthening laboratory communication.1
The routine use of dental photography is essential for excellent clinical dentistry2,3 and is a key component to the success of esthetic dentistry. This article focuses on clinical photography as the backbone of communication with the laboratory, describing the photographs that are necessary to communicate effectively and demonstrating how to properly use clinical photography for shade taking and communicating design details prior to the fabrication of the final restoration.
Communication Needs
To ensure that all of the necessary information is consistently provided to the laboratory, an office system must be implemented that includes photographic protocols.4 Most of the time, technicians are not physically able to meet the patients whose cases they are working on, so photographs and videos enable them to see lip movements in both postured and uninhibited facial expressions.
A technician can create a virtual facebow and a smile design using just a few photographs; however, with more information, the clinician and the technician can cross-check accuracy and detect errors before any provisional or definitive restorations are created. For example, if the clinician takes an inaccurate facebow but also takes a photograph showing the patient's head position with the facebow in place, the error becomes easier to notice by either the clinician or the laboratory technician. In addition, if the laboratory has a full-face photograph with the lips retracted and perfect head position that is level with the horizon, the technician can orient the maxillary arch within the framework of the face even without an accurate facebow. This system of checking and cross-checking minimizes chairside problems and increases accuracy when implementing the desired smile design.
Clinical Photography
A complete series of clinical photographs will capture the information necessary and allow the teeth and the smile to be viewed from all perspectives to identify potential challenges before they occur. All technicians can use this system, whether they are designing teeth digitally or through more traditional techniques, such as using stone models with wax-ups.
Full-Face Series
The recommended full-face clinical photographs include the following:
• Repose. This view shows the lips and the amount of tooth display at rest. It is used to understand the reasons for the amount of tooth displayed and make decisions about how to position the incisal edge. For example, individuals may display more tooth structure because they have a short upper lip length, not necessarily because they have longer teeth.
• Full smile. This reveals how much the lip moves in a postured smile. Many individuals have greater lip dynamics than this photograph reveals, which can be detrimental to the final outcome if the full range of lip motion is not recognized. The uninhibited lip position can be captured using video while engaging the patient in conversation and laughter. A Duchenne smile photograph can also be used for this purpose. Both postured and uninhibited lip positions are important in understanding a patient's full lip mobility (Figure 1).
• Full smile with teeth apart. This shows the incisal edge smile curve and allows clinicians to determine if it follows the smile curve of the lower lip, exhibiting balance and harmony (Figure 2).
• Lateral smile 45° right and left. The lateral views are important because lip asymmetry or the visualization of esthetic issues can vary from right to left and are not always visible in the frontal view (Figure 3).
• Straight profile. This permits the horizontal position of the maxillary incisal edge to be examined to determine if it is too facial or retroclined (Figure 4).
• Facebow. Although this may not be necessary when using fully digital design, it is necessary for technicians who are using analog techniques. It is also useful in helping the clinician visualize the symmetry of the face and how it relates to the plane of the horizon. Kois Facial Reference Glasses were used to aid in the accuracy of this facebow photograph. There are flags on both sides of the glasses with red on one side and green on the other. The flags exhibit no color when the head position is neutral, and if either color is visible, it can be easily determined whether the head is tipped upward or downward (Figure 5).
• Stick bite. This view enables technicians to cross-mount models more accurately, but it may be unnecessary for digital designs (Figure 6).
• Full face retracted. This allows an unobstructed view of the position of the dentition as it relates to the face. It is also the photograph that technicians use if they want to superimpose a model, a scan, or an intraoral photograph and see it in the patient's face (Figure 7).
• Twelve o'clock. This demonstrates where the teeth fall on the lip and whether the new smile needs to be moved facially or lingually in relation to the wet/dry line. It also facilitates the visualization of any transverse asymmetries that cannot be detected with straight smile photographs (Figure 8).
Close-Up Series
The recommended close-up clinical photographs include the following:
• Repose (Figure 9)
• Full smile (Figure 10)
• Full smile with teeth apart (Figure 11)
• Lateral smile 45° right (Figure 12)
• Lateral smile 45° left (Figure 13)
• Retracted with teeth apart front (Figure 14)
• Retracted with teeth apart right (Figure 15)
• Retracted with teeth apart left (Figure 16)
It is important to note that although many of the close-up series photographs could be simply cropped from the full-face views, the quality and resolution will vary depending on the camera that was employed, and poor resolution may prevent the photographs from being useful. Taking the close-up series separately ensures higher-quality photographs and provides, yet again, another means of cross-checking for accuracy.5
Shade Matching
Accurate communication of the shade selection is critical to successful esthetic dentistry. There are specific photographs that can increase the likelihood of an ideal shade match and delivery. Unless a ceramist can come to the office to take a custom shade, the only way to communicate shade and characterization requests is by using this specific set of photographs.
Although it is more critical when matching only one or two teeth, the shade should always be taken the minute that the patient sits down in the chair. This is done to avoid any dehydration of the tooth prior to shade selection. Dehydration can severely affect the accuracy of the shade matching process (Figure 17).6
Shade photographs should be taken using more than one shade tab. The shade of the tab may not be an exact match to the tooth being shade mapped, so the technician is better able to select the proper color of the final restoration without having to guess at what adjustments may be needed. Every photograph of a shade tab and tooth should also be accompanied by a black and white photograph of that tab and tooth (Figure 18). This is important in determining the value of the tooth, which is the most critical and important aspect of shade matching. Value is defined as the amount of gray present using a scale that goes from white to black (Figure 19). An incorrect value almost always leads to a result with poor esthetics. The value photograph can be taken by adjusting the camera's "picture style" setting to monochrome, resulting in a black-and-white photograph, or by importing an original color photograph into postediting software (eg, Adobe Photoshop®, Adobe Lightroom) and then converting it to a black-and-white photograph.
A gray card photograph is necessary when matching single central incisors (Figure 20 and Figure 21). A gray card (white_balance® gray reference card, Emulation Sascha Hein) is particularly suitable to enable objective shade communication between the dental office and the dental laboratory.7 The photograph is taken at a specific magnification ratio so that it can be easily replicated in the laboratory, and it requires polarized filters on the camera. After the photograph is imported into Adobe Lightroom, a numerical value can then be applied to areas of the tooth, allowing the technician to determine if the ceramics are of the same numerical value as the restoration while it is being created. Not all ceramists are familiar with this process; however, it is a particularly effective tool for assigning objective values to a subjective topic, such as shade mapping, and improves the likelihood that the final restoration will demonstrate an excellent shade match.
Polarized photographs should be included when shade matching natural anterior teeth.8 A polarized photograph can be taken with a cross-polarization filter. This filter simplifies the removal of unwanted reflections on the teeth caused by the flash. Reflections can obscure details of the teeth and cause problems during laboratory communication. These details are crucial for a ceramist, especially when matching one or two anterior teeth. Tooth characteristics, including incisal translucency, halo effects, chroma intensities, and ochre and white characterizations, are much more clearly visible when the highlights from a conventional flash are removed. The result is a much clearer "road map" for shade-matching success.
Conclusion
Clinicians routinely decide what products, tools, and systems to implement in their daily practice. Whether employing a digital workflow or a traditional one, the systematic use of photography is essential to achieving the highest levels of esthetic success. It is important for the dentist and laboratory team to develop a photographic series that enables efficient and effective communication so that treatment plan execution proceeds smoothly without the need for remakes. High-quality photography produced by a digital camera is the key component that allows this relationship to succeed, resulting in excellent care for our patients (Figure 22 and Figure 23).
About the Authors
Adamo E. Notarantonio, DDS
Private Practice
Huntington, NY
Clinical Instructor
Honors Aesthetic Program
New York University
New York, NY
Amanda Seay, DDS
Private Practice
Mount Pleasant, SC