How good are your before and afters? In this blog, Clinical Photography Expert Timothy Zoltie explains how a clinician's choice of equipment ensures the best clinical dental photographs.
Timothy Zoltie is a multi-award winning medical photographer based in Leeds, UK. He is Head of The Medical & Dental Illustration Unit at The University of Leeds School of Dentistry, and director of Clinical Photography UK Ltd which provides medicolegal photography for solicitors and insurance firms nationwide.
They say, "A workman should never blame his tools", yet in the case of dental photography, the wrong tools could lead to missed pathology, perspective distortion, or even painful retraction. The right tools are therefore just as important as the techniques applied in order to achieve standardisation and accuracy.
The uses of dental photography are clear; for treatment planning, medicolegal documentation, patient communication, clinical referral, and marketing to name a few. However, this article is not aimed at addressing the importance of dental photography but providing tips and tricks based on the choice of equipment used within the Dental Photography Department at The School of Dentistry in Leeds.
Photo by freestocks.org on Unsplash.
How to choose a camera, lens and flash for dental photography
I often get asked “Nikon or Canon?”, or “What about Olympus, I hear they make good cameras”. The choice between camera systems is negligible. That is because 90% of camera features won’t be used during dental photography. The choice of equipment will be made on the availability of the 3 main ingredients: Camera body, macro lens, flash, and the user preferences for each. So what would I recommend?
- Camera: Any Digital SLR is a solid choice, although mirrorless cameras now offer similar specifications in a smaller and lighter form factor. This can be especially beneficial in avoiding repetitive wrist strain. The availability of a suitable lens must be considered before purchasing a camera body.
- Lens: A 100mm/105mm macro lens is a must, as it keeps the user at a safe working distance from the subject whilst avoiding perspective distortion. It also offers a magnification ratio of 1:1.
- Flash: A ring flash helps eliminate shadow and is ideal for intra-oral, but is less useful for extra oral photography as it is less powerful from a distance. If undertaking extra-oral, I recommend an external Speedlight with flash off-camera cable. This enables a more powerful flash to be placed alongside the lens barrel to achieve adequate exposure while avoiding background shadow.
How to choose a mirror for intra oral photography
There is no shortage of choice when picking a mirror for intra oral photography:
From coatings such as chronium or titanium, to different shapes, sizes and handle or no handle options. There are plenty of advantages and disadvantages of each.
Image one: Long length palatal mirror helping avoid fingers in shot. Image two: Short length palatal mirror with fingers in shot. Photo courtesy of Timothy Zoltie.
"We use two mirrors – a child palatal and a large palatal mirror from DB Orthodontics".
We do not use a handle, as the temptation is to use it to lever the mouth open which is not only uncomfortable for the patient, but often results in the mirror resting on the distal surface of the molars.
Having a custom long length large palatal mirror from DB Orthodontics enables the user to avoid unintentional fingers in the shot (see image below) and avoids resting the mirror on the area of interest. It also offers the ability to switch mirror ends, allowing two options for varied mouth widths.
Creating ideal retraction for a full view
Similar to mirrors available on the market, retraction equipment also has a plethora of options to choose from. Ultimately the choice of retraction equipment should be made on the subject you are photographing. When undertaking anterior and oblique buccal views, we use the 3.5cm side of a large retractor, however when undertaking upper and lower occlusal views we switch to a small retractor.
Image one: Small retractor provides more vertical retraction for views of the gingiva. Image two: Large retractor provides more horizontal retraction for a full view of the anterior surface. Photo courtesy of Timothy Zoltie.
Why use different size retractors?
The reason we do this is down to horizontal vs vertical retraction. During anterior views we require retraction all the way back to the molars, and a more horizontal lip retraction is preferable (unless focusing on the Gingiva). It is uncommon to achieve both vertical and horizontal retraction of the lips therefore one must be prioritised over the other (see below examples)
When undertaking mirror views, two small retractors allow for adequate retraction of the upper lip. Moving the retractors from a horizontal placement to a 45 degree angle helps avoids the front lip covering the occlusal surface of the incisors.
What are contrastors?
Contrastors are a simple tool for eliminating unwanted detail and backgrounds, providing focus directly on the subject. (see example below):
Anterior lipped contrastor used to portray desquamative gingivitis. Photo courtesy of Timothy Zoltie.
Besides creating a more aesthetically pleasing image through the use of a plain black background, contrastors also help in portraying contour and shape by providing background separation. This can be useful in displaying the anatomy of the incisal edge, translucency, and extent of diastema.
There are many more factors to consider when undertaking dental photography that go beyond the scope of this article but should be researched further. These include guidance on choice of encrypted hard drives and computer equipment for the adequate processing and storage of images, which is ever more important with the recent implementation of GDPR. Cassettes for protection during sterilisation should also be considered, and buccal mirrors can be a useful addition to any photography kit.
Learn from the photography expert and gain the essential tips.
Timothy Zoltie and DB Orthodontics have joined forces to provide the ideal photography course, tailored specially for dental professionals.
"Dental Photography, Portraiture & Video in Everyday Practice" 6.5 CPD points
This course will teach all aspects of intra and extra oral dental photography, along with additional sessions on portrait photography and videography. It will provide an in-depth, insider perspective on dental and oral photography taught by specialist dental photographers. It is aimed at both beginner and intermediate level, and attendees are welcome to bring their own equipment, though photographic equipment will be provided.
The course will be a mix of theory and practical hands on workshops, enabling attendees to have a go at various aspects of dental photography to improve and capture their daily dental practice.
- Demonstrations on key pieces of equipment inclusive of camera equipment and retraction kits.
- Demonstrations on use of ISO, aperture, shutter speed, colour balance and understanding the outcomes of adjusting each.
- How to undertake standardised extra oral and intra oral photography.
- Tips on the advantage and use of clinical and non-clinical video & workshop on capturing patient testimonials.
- Consent, Legal and ethical issues in dental photography including information governance and file naming conventions
- Use of editing software and what constitutes photographic manipulation.
Dates and venues
Fri 23rd Nov 2018 - Iris Murdoch Building, University of Stirling, Stirling.
Tues 4th Dec 2018 - Crowne Plaza, Manchester City Centre.
Fri 11th Jan 2019 - Double Tree by Hilton Islington, London.
Places are expected to fill up fast, so make sure you reserve your place asap.