1. Department of Oral Pathology, Radiology, and Medicine, The University of Iowa, 801 Newton Road, Iowa City, IA 52242, USA
2. Department of Preventive and Community Dentistry, 801 Newton Road, Iowa City, IA 52242, USA
3. Department of Radiology, The University of Iowa, 200 Hawkins Drive, Iowa City, IA 52242, USA