Methods: The development of the standardised technique considered both the photographic system and the procedure. The development of the photographic system itself followed a previously described three-stage process:
1.A systematic decision making process that resulted in a preliminary plan of the primary elements of the system
2.The development and testing of a prototype
3.Quality checks of the finished system.
Results: Five primary elements were identified – conventional film vs digital system, camera, flash, positioning device, and geometric and colour standardisation reference.
Digital photography was selected over the digitisation of conventional film for cost, convenience factors, and the data loss that occurs with the digitising process. A Canon EOS 20D Body Prokit and EF 100mm Macro Lens were selected. The EOS 20D is an advanced 8.3-Mpixel SLR camera with a CMOS sensor and a solid but light body. At a magnification of 1:1.5 this system allowed capture of approximately four adjacent teeth and a reference marker. The selected Canon MT-24EX Macro Twin Lite point flash reduced the specular reflection associated with ring flashes. Manual settings were used for all images. As commercially available grid screens are not available for this camera, the custom made positioning jig incorporated an adjustable reference grid. CasMatch (BEAR Medic Corporation, Japan) was selected as the reference, enabling both geometry and colour standardisation.
Conclusion: Enamel white spot lesions may be monitored longitudinally using an integrated and standardised digital photography technique incorporating a point flash system, a custom-made positioning guide and a CasMatch standardizing reference.