A Simple Device for Taking Standardized Intra-Oral Photographs

Standardized intra-oral photographic device is very useful for longitudinally evaluating plaque accumulation or degree of inflammation. Many devices are developed for this purpose, but most of them seem to have some short-comings for simple clinical use. A simple device for taking intra-oral standardized photographs with high reproducibility was developed. The device is composed of a camera (Medical Nikkor, Auto 1: 5.6, f=200mm), a circular attachment to the lens of the camera made of acrylic resin, and a distance-adjustable tripod connected to the attachment. Using this device, intra-oral photographs of labial aspects of upper central incisors were taken. The subjects were ten dental students and two faculties. Two examiners (K. I., M. F.) took photographs once a day for one subject. Reproducibility of this device was studied calculating repeatedly the area of the same tooth surface on slides which were projected on a section paper (5mm square). The distance between two special points on a tooth was also calculated for studying the reproducibilty of the device. The average coefficient of variation for the area of a tooth was 3.2%, and 1.6% in the case of the distance between two special points of a tooth. From these results, this device seemed to be a very simple method for taking standardized intra-oral photographs with high reproducibility.