An intelligent view box system for cephalometry

In the routine analysis of cephalometry, the orthodontist usually needs to manually draw the tracing paper with the help of the view box, and then some cephalometric measurements are performed to evaluate growth aspects of the skull and the effects of treatment. Due to the varied display quality and clinical training, many orthodontists rely heavily on the view box rather than the computer monitor for cephalometry. Without the appropriate and affordable digital imaging devices, the computerized analysis for cephalometry is hard to apply in practice. In this paper, a novel design of an intelligent view box that combines an X-ray film view box, a touch panel, and analysis software is proposed. It is designed for acquiring both the landmarks and feature curves of the cephalogram for the automated cephalometric system use. There are two merits of the proposed system. One is that the relationship between the label and position for manually defined landmarks may be automatically corrected, and the other is that the manual drawing process may be automatically followed and guided based on the cephalogram. In addition, the proposed system also includes an image manipulation system. Thus, both the landmarks and feature curves may be automatically and correctly overlaid on the cephalogram for further assessment. From the experimental results, the repeated repositioning of the pen in ten times only produces a standard deviation not more than 0.5 mm in x and y directions. The spatial resolution for the proposed intelligent view box system is about 164 pixels/inch. It is demonstrated to be very useful in the clinics for the automated cephalometric analysis.