Recently, various modalities such as magnetic resonance imaging (MRI), computed tomography (CT) including cone beam CT, ultrasonography, and nuclear medicine including positron emission tomography (PET) CT are also available for the diagnosis of many kinds diseases in the oral and maxillofacial regions. Many kinds of diagnostic studies on the respective modality mentioned above should be published in oral and maxillofacial regions. Therefore, we have also studied the clinical researches in oral and maxillofacial regions using imaging diagnosis. The present manuscript introduces clinical researches in oral and maxillofacial regions using imaging diagnosis based on our present and previous studies.