Saturday, 25 October 2014

A Guide to Photography in Dentistry

My latest Study Day was with Dr Ian Cline about Dental Photography.
This is a topic that isn't really taught much at Dental School - certainly in Newcastle whenever I required clinical photographs I booked my patients in with the resident Dental Photographer.

Here I will summarise the key points of the day which was really informative and fun too as we got to practise taking photos of each other! 




What Makes a Good Photo?

  1. Focus - how clear the photo is
  2. Framing - what is in the photo i.e. the only things including in the frame are the areas of interest
  3. Exposure - the photo is not too light or too dark

How does the Image Travel through a Camera?


  • It image enters through the Lens - this focuses the light 
  • The Aperture then controls how much light enters the camera
  • The image is then detected on the Digital Sensor of the camera

What is exposure?
This is how light or dark the image is.
This is affected by 3 things: time (i.e. shutter speed), the aperture and light 

What is Aperture?
Also know as F Stop. This is the opening into the camera which allows light through.
This ranges from a big opening e.g. F2.8 to small openings e.g. F22
The aperture determines the depth of field i.e. the area in the image that appears sharp.
A small aperture creates a shallow depth of field, whereas a greater aperture creates a sharper overall image.

What is ISO?
This is the sensitivity of the digital sensor. The Lower this value, the less sensitive the camera is to light and the less 'noise' is created in the image

What is White Balance?
This is the change of the overall colour of the image e.g. auto, daylight, shade, flash, fluorescent etc. This can be changed after an image is taken.

What is Flash Exposure Compensation?
This is a setting on some cameras to compensate for the flash being too dark or light. You can use this to highlight translucencies.

What is Cross polarisation
This is effectively a 'sunglasses' attachment for the camera flash which takes out glare. Useful when taking shade photos for your technician


Photographic Views in Dentistry and Camera Settings


1. Smile (left, right, centre; natural, forced, relaxed, retracted) 
    Centre view - Focus on the canine for maximum depth of view and centre on the central incisors
    Right and left views - focus and centre on the lateral incisor
    F22 aperature and magnification ratio 1:3

2. Anterior Close up
    F22 aperature and magnification ratio 1:1.5
    Use a contraster and focus on the central incisor for centre views or the lateral for left or right views

3. Occlusal 
    F22 aperature and magnification ratio 1:3
    Warm a mirror (this prevents fogging)
    Focus on the midpoint between the premolar occlusal surface and the midline of the palate
    Centre on the horizontal through the premolars and the vertical through the midline

4. Portrait (relaxed, smile teeth apart, smile relaxed, profile, 3/4 profile)
    Useful in orthodontics
    Use a plain background ideally black or white
    F11 aperature and magnification ratio 1:10
    Focus on the eyes and teeth
    Use an anti-red eye function
    Include just below the chin and the top of the head
    Centre on the midline of the face
    Use pop up flash rather than ring flash



All modes should use a fast shutter speed of 1/200 - this prevents blurring

The ISO should be set for as low as possible such as ISO 100 apart from portrait views which should be set for higher values to allow more light in.

The White Balance should be set for Flash mode as you should always use a flash in dental photography.




A natural centre smile view of my teeth - you can clearly see the areas of hypoplastic enamel.

What Camera Equipment do you need?


Dr Cline stated that by far the best camera to take clinical photographs is a SLR camera.
Whilst you can take ok pictures of some of the views with compacts or even an iPhone, SLRs are the best quality camera to pick up fine details.

Components to a clinical camera:

  1. Camera body 
  2. Lens (100mm macro is the best for close up work)
  3. Ringflash

Nikon, Canon or Sigma were brands recommended by Dr Cline and all together it should cost around £1000
This is a lot of money for young dentists (especially if you're thinking of buying loupes too), but it's a good investment for the future and you could always save a bit of money on the ringflash by buying a cheaper make called a Skyblue that can be found on amazon. 

If you can't afford this at the moment you can buy flash and magnification attachments for smart phones e.g. SmileLite or even lenses for compact cameras. 


An example of an SLR camera with a 100mm macro lens and a ringflash.


Other Equipment you will need



  • Retractors (these can be seen the in title photo - cheek and occlusal retractors)
  • Mirrors (different sizes, with handles if possible)
  • Contrasters (these stop distractions in the image)
  • Consent forms


Uses of Clinical Photographs


  • Clinical case presentations
  • Medico-legal reasons to keep in the patient's records
  • Lab communication - demonstrate multiple shade tabs, zooming in for translucency/white spots, colour mapping. Use different angles to show different characteristics. Can take pictures of preps too which is important for all ceramic restorations 
  • Orthodontic work
  • Bleaching to demonstrate shade changes
  • Marketing


So do I have a SLR camera to use to take dental photographs? 

I'm afraid not at the moment. I am currently using my own camera which is a compact camera with a 14-45mm lens which takes good smile and portrait photos but doesn't capture the detail of close up views quite so well.
I will definitely invest in some sort of SLR sometime soon though, you can definitely tell the different between the quality of the photographs. 
Maybe I'll but it on my Christmas list - together with Loupes and my ARF. Let's hope Santa is generous this year!

For more information and for Dr Cline's presentation from the day please see his website.


Has anyone got any other tips for dental photography? What sort of camera do you use? Please comment in the section below!

Why not take a look at my other Clinical Guide posts?


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