Dr. Kwan has been published in peer reviewed journals such as the Journal of Periodontology, the Journal of the American Dental Association, and the Journal of the California Dental Association among other national and international journals, and textbooks. His periodontal practice includes clinical research, education and serving as an advisor to dental product and technology companies. John is a Diplomate of the American Board of Periodontology, and is an Assistant Clinical Professor at UCSF.

Dr. Kwan maintains a private practice in the Oakland/Berkeley area of California. His treatment focus is on minimally invasive care for periodontal and implant patients emphasizing periodontal endoscopy and microsurgery. John is currently the President and CEO of Perioscopy Incorporated, the providers of periodontal endoscopy equipment, education and technology.