1Department of Medical and Biological Engineering, Graduate School, Kyungpook National University, Daegu, Korea.
2Department of Dental Laboratory Technology, Daegu Health College, Daegu, Korea.
3Department of Dental Biomaterials, School of Dentistry, Kyungpook National University, Daegu, Korea. JFIF d d Ducky d qhttp://ns.adobe.com/xap/1.0/