Dr. Chang has been serving as the director of Maxillofacial Prosthodontics and the director of The Penn Center for Innovative & Personalized Oral Rehabilitation at the Hospital of the University of Pennsylvania and the University of Pennsylvania School of Dental Medicine. Before coming to the University of Pennsylvania, he served as the Head of Maxillofacial Prosthodontics at Cleveland Clinic and the Learner College of Medicine, Ohio (2012-2017). From 2006 to 2012, he served as the Director of Pre-doctoral Prosthodontics at Harvard School of Dental Medicine. Prior to that, from 2000 to 2006, he held a tenured endowed chair professorship and served as the director of implant dentistry at the University of Nebraska College of Dentistry. Dr. Chang has been actively involved in research focusing on the areas of Head & Neck Cancer and Craniofacial Anomalies. This field has experienced rapid growth due to collaborative interactions between maxillofacial prosthodontists, surgeons, oncologists, basic scientists, speech and language pathologists, and engineers. He is particularly engaged in applying novel 3D digital technologies to surgical and prosthetic reconstruction and conducting outcome assessments of the quality of life and physiologic functions, such as speech, deglutition, and swallowing, for patients with head and neck cancer or craniofacial anomalies