Dr. Ratnayake is a distinguished healthcare and education professional, currently serving as a Senior Lecturer at the Faculty of Dentistry, University of Sri Jayewardenepura. An alumnus of Royal College, Colombo, he earned his Bachelor of Dental Surgery (BDS) with Second Class Honours from the University of Peradeniya and completed postgraduate training at the Postgraduate Institute of Medicine (PGIM). He is a Board-Certified Specialist in Oral and Maxillofacial Surgery with a Doctor of Surgery degree.

His clinical expertise spans both local and international experience, having served in prestigious institutions such as Ninewells Hospital in Dundee, John Radcliffe Hospital at the University of Oxford, and the Royal London Hospital in the UK.

Dr. Ratnayake is also an influential figure in professional and academic circles. He currently holds leadership roles as Vice President of the Sri Lanka Dental Association, Commonwealth Dental Association, and the Sri Lanka College of Dentistry and Stomatology. He serves on several governing bodies, including the Board of Directors of the Sri Jayewardenepura Teaching Hospital, and is President of both the Government Dental Surgeons Association and the Sri Lanka Oral and Maxillofacial Surgeons Association.

In addition to his clinical and academic roles, Dr. Ratnayake has contributed significantly to shaping national health policies. He has served on advisory committees, developed national guidelines for oral cancer management, and participated in public health awareness programs. His academic contributions include multiple book chapters and research publications.