Biomaterials and regenerative medicine, stem cells and bone biology, and biolithography.

1991~1994 Children's Hospital, Boston, Research Fellow
1992~1994 Harvard School of Dental Medicine, Instructor
1994~ Seoul National University Professor
1996~1996 Harvard School of Dental Medicine, Visiting Professor
1996~1996 Children's Hospital, Boston, Visiting Professor
1997~1998 Harvard School of Dental Medicine, Visiting Professor
1997~1998 Children's Hospital, Boston, Visiting Professor
2005~2006 Seoul National University School of Dentistry, Dean of Ministry of Education
2005~2007 President of The Korean Journal of Oral Anatomy
2007~2008 Ostem Implant Co., Ltd. Executive Director / Head of Bone Science Research Institute (Concurrent Director)

1991 The Hatton Travel Award, Korea Branch of the International Dental Research Association.