Digital dental photography can be a valuable tool in restorative dentistry: it improves treatment planning, helps enhance teamwork, and facilitates great results in restorative procedures.
Dental practitioners who are new to photography, may find it hard to get started – especially when there is a wide array of cameras and equipment to choose from. Let us review some of the basics, such as the basic camera and lens types that are typically needed, how to set up manual camera settings, what accessories may be of use, how to take high-quality dental photos. Finally, we’ll provide some tips on developing a standardised photo protocol in the dental office.
Fig. 1: Popular conception of how dental imaging works
Photography is an art form that plays an essential role in restorative dentistry. Digital photographs of the patient’s face, smile and teeth are used for treatment planning and documentation, as well as for communication with the laboratory technician. Of course, in order to build a long-term, lasting relationship with the client, quality is paramount. Looking at high-resolution images can also help evaluate a clinical case. Images – in and of themselves – are useful to anyone striving for self-improvement. Last but not least, beautiful images of patients and treatment outcomes serve as a valuable marketing tool.
For the semi-professional user, we recommend using a digital single lens reflex (DSLR) camera. Examples are Canon MR-14EX, , Canon MT-24EX, Canon MT-26EX-RT, Metz MS-1, Nikon R1 / R1C1 system and Sigma EM-140DG. . In addition, a macro lens with a fixed focal length is required for internal photography. The macro lenses preferred for dental use have a focal length of 60 mm to 105 mm. They allow for a comfortable working distance with enough room for illumination.
Fig. 2: Example of suitable camera types
Once the device is available, we need to know how to use it. The automatic control mode is not suitable – it is necessary to adjust the settings manually to achieve the desired results. The three main values that need to be set are the f-number (f), the exposure time and the specific light sensitivity of the sensor (ISO).
This leads us to the selection of the external flash system. In general, ring flash systems, which emit light 360 degrees around the lens, and twin flash systems, with two light sources located on opposite sides of the lens, are commonly used in dental photography. A twin flash system is preferable for photographs of the anterior region: it provides even illumination of the teeth without eliminating all shadows, and gives the photograph a 3D effect.
In this way, surface details, colour transitions and translucency differences, etc. are brought out more accurately than with a ring flash, which illuminates the entire field from all directions. This results in a strong white spot in the centre of the image and a lack of shadow and plasticity. A ring flash is often preferred in the posterior region because it illuminates the teeth in this area better. With twin flash, the best results are obtained when using a soft diffuser.
Fig. 3: Accessing camera settings
First of all, it is useful to take a portrait photo of the patient so that information about the face and facial harmony can also be transmitted to the laboratory. Here the basic settings are slightly different and many additional factors such as lighting conditions, the right make-up etc. have an influence on the result.
In addition to taking photographs, the practitioner should also consider recording a short video sequence in which the patient speaks and smiles. The dynamic movements usually appear more natural and allow a better assessment of the real situation. This is particularly helpful, for example, in assessing the mock-up and lip and tooth dynamics.
Another tip is to develop a standardised photo protocol together with the dental technician. For a proper analysis of the character of the teeth, black and white photographs as well as those taken with a cross-polarisation filter (e.g. CROSS -POLAR filter) can be very useful. The philtre removes all surface reflections from the image, giving a deep insight into the colour characteristics of the teeth.