Abstract
Dentists and dental hygienists remove dental calculus using a cutting tool called dental scaler. The evaluation of sharpness of dental scalers requires skill which depends on sensory examination. The aim of this research is to evaluate the sharpness of scalers objectively. First, an apparatus for taking images of scalers was developed by taking into account the evaluation method of observing the cutting edge reflection used by experts. The scaler to be inspected was fixed on a turn table driven by a stepping motor. The angle of the scaler was changed by the stepping motor and images of the cutting edge of the scaler were taken at various angles by a CCD camera. Next, the area and the length of optical reflection pattern of the cutting edge were measured using some images taken from different angles. And the relation between these values and the sensory evaluation was examined. As a result, the implications between them were found out. And, it was confirmed that this method can evaluate the sharpness of scalers objectively.
