A 7.8-µm Pixel Pitch Direct Conversion X-ray Detector for High-Resolution Intraoral Tomosynthesis Application

Intraoral tomosynthesis, or 2D x-ray tomography, is an imaging technique that is currently being used in dental diagnostic imaging. Technological developments in dental diagnostic imaging have been mostly focused on improving imaging modalities or employing higher performance x-ray sources. Higher efficacy in diagnosing common dental issues, however, requires more efficient and accurate imaging systems. Small-feature size lesions, cracks, or fractures cannot be detected accurately unless a comparably higher resolution x-ray detector is employed. In this work, we investigate and demonstrate the potential of employing a high resolution amorphous selenium-CMOS hybrid direct conversion x-ray detector, with pixel size and pitch of 7.8-µm, for dental imaging application. We use a microfocus x-ray source working at 60 kVp and 199 µA to perform 2D x-ray tomography and create ultra-high resolution x-ray images. This high-resolution x-ray detector in conjunction with the microfocus x-ray source can be incorporated with many dental diagnostic imaging techniques such as stationary intraoral tomosynthesis, panoramic imaging, or cone-beam computed tomography to further improve the final image quality.