1. Department of Conservative Dentistry, Faculty of Dentistry, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia
2. Specialist Study Program of Conservative Dentistry, Faculty of Dentistry, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia
3. Nanotech Indonesia, Serpong, Tangerang Selatan, Banten 15314, Indonesia