Dr Liong completed a combined degree of Bachelor of Chemical Engineering and Bachelor of Arts majoring in Asian Studies at the University of Sydney in 2002, after which she went backpacking around Europe for a year. She then went on to finish post graduate Bachelor of Dentistry with Honours in 2008 at the University of Sydney.
Dr Liong completed her Master of Orthodontics at the University of Hong Kong in 2013 and was awarded Membership in Orthodontics at the Royal College of Surgeons, Edinburgh.
Dr Liong started her career as a general dentist on the Central Coast while also working as a preclinical tutor (part-time) at the University of Sydney in the Tooth Conservation. She volunteered multiple times performing dentistry in rural Bali for a clinic that provides free medical and dental care for children at over twenty orphanages, many of which are located in remote and isolated communities.
Dr Underhill established Edgecliff Orthodontics in 1997, seven years after she arrived in Australia. Dr Underhill completed her undergraduate dental training in Cardiff, Wales and then completed her specialist orthodontic program at the Royal London Hospital obtaining her Master of Orthodontics and Membership in Orthodontics at the Royal College of Surgeons England.