Delivering the Art of Dentistry Through Photography By Todd Ehrlich, DDS

As dentists, we are all artists to some degree. We take a lot of time and effort to turn an unfortunate situation into a beautiful, natural, and functional restoration. Ironically, we can make the best looking upper second molar restoration, and no one will ever appreciate it. Were the undiscovered works of Rembrandt or Picasso any less of a masterpiece than the ones hanging on the walls of museums? Probably not. Take photographs and share your dental masterpieces with the world.

The age of digital photography and computers makes it very easy to take a snapshot and send a picture of the grandkids to grandma, or to display the most technical dentistry. With a plan for the intended result, proper dental photography can put the dentist on a higher plane of quality and pride. A digital camera should be as readily accessible during patient care as a hand-piece. Radiographs are no longer the only visual documentation available to us. Obviously, a radiograph sees internal aspects of the human body that we can not see visually, but it is a two-dimensional picture with only shades of black and white. A photograph gives you an opportunity to record a visual topographical image with every nuance of tissue shade and restoration condition — incredible information to have! It can be used for patient education, office display, insurance coverage, liability coverage, charting of teeth, following the condition of restorations or early incipient lesions, laboratory information and increasing the dentist’s clinical skills. The list is endless with the uses of dental photography. However, the image is only as good as how it was taken and how it is displayed. So, it is imperative to focus on a few key details to make that dental photograph the best it can be.

The most critical factor of dental photography is consistency. Without consistent pictures, it makes it more difficult to use the image properly. It would be the same as comparing a bite-wing x-ray from 2 years ago that was properly taken to a bite-wing x-ray taken today that had overlapping contacts. If the dentist can become as strict with photographic technique as x-rays, the utilization of the photographs becomes priceless. This article will describe the basic techniques with special attention to quadrant photos. These principles will apply to any other dental photograph you may take.

All digital cameras are not the same. We currently have intra-oral cameras, point-and-shoot cameras, and professional SLR cameras. All of these can be used in a very effective manner as long as they are being used consistently. Most would argue that the digital SLR cameras capture the best image possible. Their resolution and zoom factor are difficult to beat. I have essentially disposed of my intra-oral cameras and gone exclusively to a digital SLR camera. Nikon, Canon, and Pentax all make very nice digital SLR camera bodies. There are many factors when choosing which brand, but they all take beautiful pictures. The lens and flash system are the most critical component and must be appropriate for dental photography. The traditional lens setup is a 1:1, 105mm macro lens which will give you the best range to capture the full face or to zoom in on one tooth. The size of the 105mm lens can sometimes be difficult with the weight and length, but the results are exceptional. With the advancement of digital cameras and digital zoom, a 60mm macro lens can be used very effectively. This lens reduces the length and weight and takes very acceptable pictures, but the doctor that is committed to the highest quality will be outfitted with a lens in the 100-105mm range for ultimate zoom. Because these lenses can take very close pictures, the illumination of the teeth is critical.

The closer the image, the more shadows affect the final outcome. A ring flash will throw light from all 360 degrees onto the teeth, thereby reducing the amount of shadowing and making for a better image. A single point flash that is found on point-and-shoot cameras will cause unwanted shadows (even with light diffusers). (See Fig. 1) Intra-oral cameras usually have adequate lighting, but are inconsistent through the entire image. Some areas of the picture will be intensely lit, while others are darker. They also lose quality due to pixilation.

When taking the quadrant photograph with a digital SLR camera and ring flash system, I recommend doing it as quickly and as efficiently as possible for consistent pictures and patient comfort. The main objectives are for the picture to be focused, the image directed down the long axis of the teeth, and for the quadrant to be aligned horizontally in the image. In order for this to occur, the assistant must be aware of these objectives. When the assistant understands them, they can easily adjust the patient, the mirror, or manipulate the cheek or tongue as needed. In order to get an angle down the long axis of the tooth the patient must open fully but be relaxed. I find that cheek retractors usually do not allow the patient to open fully, so I do not routinely use them. The teeth should be thoroughly dried before the placement of the mirror. We are accustomed to seeing saliva, but our patients will be distracted by it if they see it in the image. With one hand the assistant places the quadrant mirror on the opposite arch and with the other hand uses the air syringe to retract the cheek or tongue and to quickly dry the mirror. It is imperative that the mirror does not fog or have any droplets of saliva or water. A contaminated mirror may also disrupt the camera’s automatic focus indicators. The image is taken and immediately evaluated. The assistant and the patient should not move until the image is approved. The dentist can quickly reposition the camera and retake the image if necessary.

Your digital SLR camera should be set in the “aperture priority” mode (usually indicated by the “A” on the setting dial.) The aperture is the opening in the lens to which light passes through and has a direct affect on the depth of field focus. It can be set to be larger in diameter and allow a lot of light to come through (low F-stop) or set to be smaller in diameter and limit the amount of light to come through (high F-stop.) Larger apertures allow more light but reduce the depth of field focus. Smaller apertures allow less light but increase the depth of field focus. The best quadrant images have complete focus throughout the image and therefore require a smaller aperture setting (higher F-stop) and a lot of light from the ring flash. In other aspects of photography, such as portrait photography, it is advantageous to only have the subject in focus with the remainder of the image out of focus, but this does not work with clinical images. You have control over the size of the aperture with the F-stop settings. Each camera and lens system is slightly different with the F-stop setting and must be adjusted accordingly.

Your immediate evaluation of the image should include:

1. Is the entire image in focus?
2. Is the image over or underexposed? Usually the image is overexposed and appears washed out. Try another image with a higher F-stop value.
3. Is the quadrant of teeth positioned as horizontally as possible?
4. Can the angle be down the long axis of the teeth any better?

All pictures taken subsequently of this quadrant should be done exactly the same way. The image can be downloaded into many different imaging programs including your dental charting software. They all have the basic tools to make the picture look its best.

The key to a successful image is to enhance or highlight the subject. Our subject is the quadrant of teeth, and we want to make sure they are the focus of the image. You can take an average picture and make it look fantastic by just framing it properly. If your work of art does not have a great frame, it probably loses half of its value. (See Fig. 2) The first step is to rotate the image so that the quadrant is parallel with the horizontal plane. Be very precise with this because everything else is dependent on it. Any subsequent pictures will be rotated to this same angle. The next step is to crop away everything out of the picture that is unnecessary. If the image has to be rotated significantly because of a poor photographic technique, there will be less of an area to crop. Crop the image so that the teeth are the dominant portion of the image. You now have made your image 50% better because it enhances the quadrant of teeth and is appealing to the eye.

When making a series of pictures each picture must be rotated exactly to the same angle and cropped in exactly the same position. (See Fig. 3) Choose a landmark that is readily apparent in ALL of the pictures of the series. This could be the distal of the second molar or an interproximal contact point. If one image does not have that landmark, you must begin to limit your crop size. In other words, it will look strange if one picture out of the series has a different size because the crop was done inconsistently. This is why your photographic technique is so critical. The series of photographs will need to be assembled in software such as PhotoShop or Xara. The images of the series can easily be managed, positioned, and framed appropriately in one of these. I prefer Xara Extreme (www.xara.com) because it is intended for the graphics artist (a true vector-based software), has all of the same tools as PhotoShop, and it is less than $100.

Using the best digital camera set-up, taking the picture accurately, and managing the images consistently, you can achieve exceptional results (See figs. 4-5). Going the extra mile to make your case presentation better will enhance the value that your patients perceive of your work, your skills as a practitioner will improve, and you just might make a better post on Dental Town. Pictures do speak a thousand words, but some people tend to think posting 1000 words works just the same! They do not!

Raise the bar of your posts. Raise the bar of your case presentations. Raise the bar of your patient education. Raise the bar of your dental skills. Raise the bar of your professional enjoyment, and make your masterpiece known to the world!