image quality enhancement in digital panoramic radiograph

one of the most common positioning errors in panoramic radiography is palatoglossal air space above the apices of the root of maxillary teeth. it causes a radiolucency obscuring the apices of maxillary teeth. in the case of this positioning error, the imaging should be repeated. this causes the patient be exposed to radiation again. to avoid the repetition of exposing harmful x-rays to the patient, it is necessary to improve the panoramic images. this paper presents a new automatic panoramic image enhancement method to reduce the effect of this positioning error. experimental results indicate that the enhanced panoramic images provide with adequate diagnostic information specially in maxilla sinusoid region. hence, this technique dispenses the need for repetition of x-ray imaging.