Dr. Ngo has extensive experience in private practice, research and education. He qualified in dentistry at the University of Adelaide in 1982 and completed a Master of Dental Surgery in fixed prosthodontics in 1990. Dr. Ngo was the principal of a general practice located in the business district of Adelaide. With a staff of five, he delivered good dental care based on the philosophy of Minimal Intervention over a period of 18 years. In research, he is active in the areas of dental materials and cariology, he was appointed Visiting Research Fellow to the Adelaide University in 1998, Research Director of the Colgate Australian Clinical Dental Research Centre, Adelaide University in 1999 and Research Consultant of the centre in 2003, Associate Professor, working in the fields of Dental Biomaterials and Minimal Intervention Dentistry, to the Adelaide University in 2003. At present, his main focus in research revolves around the management of caries and the interactions between the glass-ionomers and the dental tissues. He has been a technical consultant to several dental organisations and was co-inventor of several dental products.

As an educator, he has published and lectured extensively in Australia and internationally on the above topics. He was instrumental to the establishment of the Minimal Intervention 2020 projects in Adelaide and other dental schools in South East Asia. He serves on the board of the Academy of Minimally Invasive Dentistry and the editorial board of Journal of Dentistry, Journal of Oral Health and Preventive Dentistry.