1. Department of Oral and Maxillofacial DiseasesTurku University Hospital Lemminkäisenkatu 2, 20520 Turku Finland
2. Department of Oral and Maxillofacial surgeryInstitute of Dentistry, University of Turku Turku Finland
3. Departments of Clinical NeurophysiologyUniversity of Turku and Turku University Hospital Turku Finland