Pattern Classification Techniques for the Ultrasonographic Periodontal Probe

Introduction In the clinical practice of dentistry, radiography is used to detect subsurface structural defects such as cavities and cracks. However, radiation is harmful to the patient, and has been shown to actually lead to cavities by the demineralization of teeth. Radiography can also only detect defects parallel to the projection path, and it is useless for detecting conditions such as gum disease because soft tissues are transparent to x-rays. Ultrasonographic Nondestructive Evaluation, however, is safe to use as often as indicated, and computer interpretation software makes diagnosis automatic. The structure of soft tissues can be analyzed effectively with ultrasound, and even symptoms such as inflammation can be registered with this technology [1]. One application of ultrasound (US) in dentistry, a periodontal probe, is already being developed as a spin-off of NASA technology [2]. Periodontal disease is caused bacterial infections in plaque, and the advanced stages can cause tooth loss when the periodo The usual method of detection is w millimeters (Fig. 1a). The dental h gum to measure the depth to the p and depends upon the force the hy Furthermore, this method is painfu currently under development uses ligament non-invasively. An ultras Figure 1: Manual vs US Probing: The figure compares a) manual periodontal probing, in which a thin metal probe is inserted in between the tooth and gums, versus b) the ultrasonographic periodontal probe, in which ultrasound energy propagates through water noninvasively.