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Digital Single Lens Reflex Photography in Clinical Orthodontics: Revolution Or Evolution 1Anupam Agarwal, 2Shalu Mahajan, 3Santosh Verma

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Digital Single Lens Reflex Photography in Clinical Orthodontics: Revolution Or Evolution 1Anupam Agarwal, 2Shalu Mahajan, 3Santosh Verma WJD Anupam Agarwal et al 10.5005/jp-journals-10015-1271 ORIGINAL RESEARCH Digital Single Lens Reflex Photography in Clinical Orthodontics: Revolution or Evolution 1Anupam Agarwal, 2Shalu Mahajan, 3Santosh Verma ABSTRACT factory presets, but the newer range of these cameras do The field of dentistry has witnessed a ‘Digital Revolution’ in the have a variety of customizable options available to shoot recent past which has made the maintenance of patient’s pre- and modify as per need. treatment and post-treatment records a necessary protocol. The On the other hand is, what is called as, a rich boy’s speciality of orthodontics depends heavily on patient’s records for various purposes including diagnosis and treatment planning tool- i.e. DSLR cameras (Although the DSLR cameras also and patient motivation. The recent upsurge in digital technology come in midrange price segment as well, but still they are has been both inviting and confusing as an orthodontist finds undoubtedly costlier). The strength and robust body design, himself in a dilemma regarding which camera to choose for ortho dontic photography. This research article tries to develop rapid auto-focusing systems, multiple fast exposure options, an understanding about the cameras to choose for the above and choice of different lenses are the features boasted by mentioned purpose and that whether digital SLR technology is this class of digital cameras, that increases the price of the really a revolution or just an evolution. camera. Most of these features are appropriate for individuals Keywords: Orthodontics, Camera, Photography, Digital SLR, planning to do action photography or imaging in variable Point and shoot, Resolution, Dental, Dentistry, Orthodontic photography. lighting conditions. Very few of these features, however, are of actual need for the type of imaging performed in orthodontics. How to cite this article: Agarwal A , Mahajan S, Verma S. Digital Single Lens Reflex Photography in Clinical Orthodontics: Revolution or Evolution. World J Dent 2014;5(2):118-123. BASIC DIFFERENCE BETWEEN A POINT AND Source of support: Nil SHOOT CAMERA AND A DIGITAL SLR Conflict of interest: None The main difference is how the photographer sees the scene. In a point-and-shoot camera, the view finder is a simple INTRODUCTION window through the body of the camera. Photographer does Intraoral and extraoral photography are widely used to not see the real image formed by the camera lens, but he gets document orthodontic patients at the start of treatment and a rough idea of what is in view. 1 to monitor treatment progress. Photographs are an essential In an SLR camera, he can see the actual real image that the 2 part of clinical documentation. If correctly taken, they film will see. The advantage of its design is that photographer offer more useful information about the malocclusion and can adjust the focus and compose the scene so he gets exactly 3 treatment than any other clinical record. There are two the picture he wants. For this reason, professional photogra- types of digital cameras available in the market, digital phers typically use SLR cameras (Figs 1 and 2). point and shoot (DPS) and digital single lens reflex (DSLR). The DPS cameras are named after the two steps required to ORTHODONTIC PHOTOGRAPHY: NEED BASED shoot a photograph with them, i.e. point at the object and OR PASSION BASED! shoot the image, without cumbersome adjustments of various kinds. Mostly they rely on ‘auto focus’ functions, primarily The primary purpose of taking photographs of an orthodontic patient is to maintain a record as the treatment progresses. 1,2Senior Lecturer, 3Head Orthodontic photographs are not taken out of passion for 1Department of Orthodontics, Teerthanker Mahaveer Dental photography but they are really need based. So, running after College, Moradabad, Uttar Pradesh, India com plex camera features and burning time and money for 2Department of Conservative Dentistry, Teerthanker Mahaveer that extra microscopic detail really needs a value judgement Dental College, Moradabad, Uttar Pradesh, India proposal. 3Department of Orthodontics, Kothiwal Dental College, Moradabad Uttar Pradesh, India MATERIALS AND METHODS Corresponding Author: Anupam Agarwal, Senior Lecturer Depart ment of Orthodontics, Teerthanker Mahaveer Dental College Seven point and shoot digital cameras available in the market Moradabad, Uttar Pradesh, India, e-mail: anupamagarwal83@ were reviewed for their features. These cameras were falling gmail.com in the price range between US$ 350 and US$ 450 and were 118 WJD Digital Single Lens Reflex Photography in Clinical Orthodontics: Revolution or Evolution Fig. 1: Points and shoot camera Fig. 2: Digital SLR camera consi dered to be an easy buy for most of the practising ortho- print that can be suitably achieved without distortion. All point dontists. They were far cheaper than many of the ‘mid range’ and shoot cameras had approximately the same megapixel digital SLR cameras floating in the market. values which was almost the same as that of the SLR camera. Basic to advanced features, that these cameras had, were highlighted and reviewed. A comparison was made with the Metering Technology most common features available in the digital SLR cameras The camera should have both the matrix and spot metering (taking Nikon D70s as prototype) that generally make them options. Intraoral orthodontic images have high contrast ‘the better choice’ for orthodontic photography. and if they are matrix metered then overexposure of teeth The features reviewed were: (lighter structures) can occur as exposure value is set to 1. Megapixels the averaged contrast of the whole seen, including the dark 2. Metering technology posterior areas as well. Spot metering allows only a small 3. Magnification and magnification ratio area on the tooth (preferably) to be metered and exposure 4. Sensor size is automatically set according to it. So accurate exposure of 5. Viewfinder the intraoral image occurs. 6. Exposure compensation All the cameras that were included in the study showed 7. Histogram options for both type of ‘Metering’, i.e spot metering as well 8. Macro photography capability as matrix metering. This feature makes them comparable to 9. Grids the digital SLR cameras (many of us do not even know that 10. Interchangeable lenses point and shoot cameras have this function!). 11. Customizable aperture and shutter speed settings For extraoral photo shots matrix metering option can be 12. External flash options chosen, which was also available in the cameras. 13. Price (in US$). Magnification and Magnification Ratio RESULTS A magnification ratio of 1:1 means that the image produced The results obtained and tabulated after a thorough review on the sensor/film is of the same size as that of the actual object. of the cameras under consideration are presented in the This is highly desired for intraoral shots. When we press the Tables 1A and B. ‘zoom’ button then lens changes its focal length by increasing the distance from the sensor/film and we achieve consistent DISCUSSION magnification that is required for intraoral photographs. The digital point and shoot cameras have a lot of features All the point and shoot cameras had optical zoom in the that are comparable to DSLR cameras (at least in the sense range from ×3 to ×10 (one even showing ×15), meaning that of their presence if not to the extent). they can actually double or triple the size of the teeth in the intraoral shot. Megapixels Whereas in DSLR cameras since the focal length of the Megapixels refer to the extent of close packing of the pixels macro lens is same , the magnification can not be increased in an image. It is also suggestive of the possible size of the or decreased readily. World Journal of Dentistry, April-June 2014;5(2):118-123 119 120 Agarwal etal Anupam Tables 1A and B: Tabulated results after review of the cameras A. Parameters Sony Sony DSC-T900/s Sony DSC-T90/P Sony DSC-H50/B Sony DSC-H20 Nikon coolpix S70 Nikon coolpix Nikon D70s DSC-TX1/H S640 Megapixels 10.2 megapixels 12.1 megapixels 12.1 megapixels 9.1 megapixels 10.1 megapixels 12.1 million 12.2 million 12.2 million Metering technology Multipattern/ Multipattern/center Multipattern/center Multipattern/center Multipattern/ Multipattern/center Multipattern/ Center weighted/spot center weighted/ weighted/spot weighted/spot weighted/spot center weighted/ weighted/spot center weighted/ spot spot spot Magnification and 4:1 4:1 4:1 15:1 10:1 4:1 4:1 1:1 to 1:10 magnification ratio Sensor size 1/2.4 exmor 1/2.3 super CCD 1/2.3 super CCD 1/2.3 super CCD 1/2.3 super CCD 1/2.3 in CCD 1/2.33 in CCD 23.7 × 15.6 mm CCD CMOS sensor Viewfinder/LCD Viewfinder + LCD Viewfinder + LCD Viewfinder + LCD Viewfinder + LCD Viewfinder + LCD Viewfinder + LCD Viewfinder + Viewfinder + LCD display display display display display display display LCD display display Exposure Plus/minus 2 EV, Plus/minus 2 EV, 1/3 Plus/minus 2 EV, 1/3 Plus/minus 2 EV, 1/3 Plus/minus 2 EV, Absent Absent Present compensation 1/3 EV step EV step EV step EV step 1/3 EV step Histogram Present Present Present Present Present Present Present Present (but can’t be used in real time) B. Macro Close Approx. Magnifying Magnifying Macro Macro Macro Macro Macro lens photography focus 1 to glass mode glass auto focus auto focus function function has to be capability enabled 20 cm approx. mode range range (3 cm) (2 cm) attached range 1 to 20 cm approx. approx. approx. 1 to 20 cm 1 cm to 2 cm to infinity infinity Grids Present Present Present
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