Kohei Shimizu, D.D.S., Ph.D., is an Associate Professor in the Department of Endodontics at Nihon University School of Dentistry, Tokyo, Japan. He is a board-certified endodontist and clinical instructor with extensive experience in endodontic diagnosis, root canal treatment, and the management of complex odontogenic and orofacial pain. His research focuses on post-endodontic pain, post-traumatic trigeminal neuropathic pain, and the mechanisms underlying persistent occlusal pain after dental treatment. In particular, his work explores the relationship between periodontal ligament sensory input, trigeminal nerve sensitization, and pain adaptation after endodontic procedures. He has also investigated potential therapeutic strategies, including pharmacological treatment with mirogabalin and active functional loading, for patients with neuropathic pain following endodontic treatment. Dr. Shimizu has published clinical and basic research articles in the fields of endodontics, orofacial pain, and neuroinflammation. His current research integrates clinical observation, quantitative bite force assessment, and experimental animal models to clarify the biological mechanisms of post-treatment pain and to establish new diagnostic and therapeutic approaches in endodontic practice.