1. College of Dental Medicine—Illinois, Midwestern University, Downers Grove, IL 60515, USA
2. Facial Pain Specialists, San Diego, CA 92121,USA
3. Division of TMD and Orofacial Pain, University of Minnesota Schoof of Dentistry, Minneapolis, MN 55455, USA
4. Minnesota Head and Neck Pain Clinic, Plymouth, MN 55447, USA