168 醫藥人 楊幽幽 牙線功效成疑 Editor-in-chief Online Journal of Dentistry User 楊幽幽牙科醫生教育系列Dr Cecilia Young Oral Health Education on YouTube, 08 Nov 2017 醫藥人 楊幽幽 牙科醫生 Dr. Cecilia Young Yau Yau Editor-in-chief Online Journal of Dentistry