Digital dental photography with Peter Gordon
The two most important accessories in dental photography are mirrors and retractors. Both of these accessories can determine the quality and appearance of the final photograph, and thus, the dental professional’s reading of the clinical photograph. As noted in previous articles in this series, each dental professional will have specific requirements, so there are a number of suitable options available.
This post will detail accessories and tips to consider when taking a standardised
Most intra- and perioral views are taken within 15-30cm from the patient, with the
chair backrest set at around 70 degrees. For chairs without a leg break, it is impractical to take these views from the foot of the chair, so it is recommended that the pictures are taken from the side of the chair with the patient turning his/her head appropriately.
Some dentists prefer to take a mirror view of the upper arch from behind the head
with the patient lying horizontally. In this instance, it is imperative that the camera has a strap and it is securely strapped around the photographer’s neck.
In the author’s opinion, the most important mirror is an occlusal one – preferably long, to avoid including fingers in the field of view. Handles are available to attach to 3mm thick mirrors if you possess them, or are considering purchasing a shorter variety.
Above are the most popular shapes of mirrors widely available on the market.
For the majority of restorative dentists, good retraction will achieve satisfactory buccal views taken directly.
For orthodontists and those requiring a right angle view of premolar and molar teeth, a buccal mirror would be considered essential. In reality, with automatic exposure, the reflectivity of the surface is less important than it was 30 years ago, however, the surface does play a part in the longevity of the working life of the mirror.
High quality polished stainless steel mirrors are excellent and do not break if dropped. Their surfaces are more prone to scratching, so great care in handling when cleaning and sterilising is of maximum importance.
The Jakobi range is designed to work with a special demisting handle below but can be purchased individually if metal mirrors are required. They are highly polished on both sides.
The Jakobi demisting mirror unit has an illuminated handle plus a fan that blows air
onto the mirror surface and eliminates any fogging problem. There is a full range of 1.5mm stainless steel mirrors for it. The unit will not accept glass mirrors, which
are usually 3mm thick.
The most important factor is that the mirrors are surface-coated to eliminate a double image. The current mirror options are mainly chrome or titanium coated, the latter, though more reflective, also have a more scratch resistance surface.
Once again, careful handling is paramount. Ideally, mirrors should be individually
wrapped and perfectly clean when bagged. Invariably, titanium-coated mirrors are
surfaced on one side only, but double-sided titanium-coated mirrors are available.
Sterilising racks are available that also keep mirrors separate.
The most important mirror is an occlusal one
– preferably long to avoid including fingers in the field of view
Retractors can be subdivided into metal, plastic and polycarbonate, and then further subdivided into self-spanning and single ended units.
Plastic retractors tend to deteriorate with age but offer the greatest variety. Choice
tends to rest with the operator but some have specific advantages.
The benefit of a self-spanning retractor is that it is very easy for the patient or dental nurse to pull the tabs forward for an anterior view to open up the buccal corridor and to ‘push/pull’ appropriately for buccal views.
Combination retractors have the advantage of combining ‘standard’ cheek
retraction with occlusal retraction.
V retractors allow excellent views of buccal teeth without resorting to mirrors.
‘A’ retractors are sold as ‘universal’ and ‘B’ and ‘C’ are made in adult and child sizes.
When using any single-ended retractor to capture a buccal view, always place a retractor in the opposite side to avoid the upper lip drooping over the incisors.
The Oringer retractor – a metal equivalent to the plastic self-spanning retractors – is also available in three sizes.
The author found this retractor particularly useful while photographing an implant case as it remained in place throughout the procedure. The patient’s lip looked quite distorted postoperatively but recovered soon afterwards.
Self-spanning units can cause a mid-line lip droop, but this can be reduced by placing a rubber band around the retractors.
These accessories separate the subject from distracting areas and are available as anterior and occlusal types.
Contrastors all do the same job – they are either horseshoe shaped for upper and lower occlusal views (most manufacturers have a range of three sizes) or spatulate for anteriors.
They are usually made from black anodised aluminium, which is vulnerable to scratching – though they are increasingly available covered in silicone, or as bendable copper covered in silicone.
Tips for facial views
If you do not have a suitable background wall or wish to take facial views in the chair, purchase a suitably coloured A2 mounting board – generally speaking, light grey or blue is quite practical.
All flash guns will create some shadowing: ring flash units create a halo, while point units a harsher shadow opposite the flash unit’s position.
Naturally, black backgrounds will eliminate shadows, but you may find that they also
camouflage dark-haired patients! If a ‘ring flash’ with two tubes is used to take profiles or three quarter views, switching off or covering the flash tube opposite the nose side throws the shadow behind the hair, leaving a shadow-free profile.
A simple and economic device known as a ‘slave flash’ can be placed behind the subject and in front of the background. This is wirelessly triggered by the main
flash and washes out the shadow without affecting the exposure to the subject. If the clinician has a spare flash unit without slave capability, this functionality can be added economically by purchasing a ‘slave trigger’.
Specialist background light boxes are available and large X-ray viewing boxes can be used to achieve shadowless portraits.
Brackets are available to place flash units either near the lens or extended horizontally further away as discussed previously (Implant Dentistry Today 9(5): September 2015). These systems can become even more complicated if diffusers are placed on the individual flash units. The sole object of this exercise is to reduce the flare when taking close-ups of anterior teeth.
However, in practical terms, it is not convenient to reset flash units from one position to another and if the ultimate aesthetic results are sought, the author recommends using two separate camera systems.
If frequent theatre use is contemplated, then thought should be given to a longer
focal length primary macro lens, for example, a Sigma 180mm macro, or the ‘standard’ 100mm lens with a 2x converter.
In both situations a more powerful flash set-up would be required, and in view of the weight, the use of a monopod could be considered.
Various devices are available for transmitting images wirelessly from the camera.
One method of note involves using Wi-Fi enabled SD cards, such as Eye-Fi and Transcend. To the author’s knowledge, the Eye-Fi will transmit to one device, like an iPad or PC, and the Transcend will transmit to two.
If two or more cameras are operating these systems in close proximity, interference could be a problem.
The Camranger is another option that, albeit far more expensive, will also transmit
images very satisfactorily. This system adds a range of wireless functionality to the camera, hence its relative expense.
There are also two systems available that allow the images to transmit from the camera directly into patients’ notes wirelessly, such as Kitview, which can be set up to various software systems, and Examine Pro (Software of Excellence).
About the Author
Peter Gordon LDSRCS DGDP(UK) is one of the UK’s most experienced dental photography experts. He was in private practice from 1969 until 1998, when he joined the Dental Reference Service, introducing photography there with great success. Together with Philip Wander, he is the author of Dental Photography (published by the BDJ in 1987). Peter was a BDA adviser between 1991 and 1996, and has lectured worldwide on clinical photography. He is currently a director of Photodent, a company that helps dental teams achieve the finest results in dental photography.
If you're in the market for a new set of mirrors and retractors
and would like to demo our JAKOBI Dental Mirror System