title: No signs of metabolic hyperactivity in patients with unilateral condylar hyperactivity: an in vivo positron emission tomography study.
abstract: OBJECTIVE
  The purpose of this study was to assess bone growth and blood flow in the condylar region in patients with unilateral condylar hyperactivity (UCH) by use of positron emission tomography (PET).
  
  
  METHODS
  This prospective study included 7 patients with UCH and a control group of 6 volunteers. In addition to normal clinical investigations, labeled fluoride ((18)F(-)) and oxygen 15-labeled water (H(2)(15)O) PET scans were performed.
  
  
  RESULTS
  In control subjects the net rate of fluoride influx, representing bone metabolism, was similar for left and right condylar sides. Interestingly, this was not significantly different from the affected condyles in UCH patients. Rather, the net rate of fluoride influx on the contralateral side of UCH patients was reduced significantly compared with the affected side (P= .02) and control subjects (P= .004). The mean blood flow on the left and right condylar sides in control subjects was not significantly different. The same was true for the hyperactive and contralateral condyles of UCH patients. Blood flow in the condylar region in UCH patients was similar to that in the control group.
  
  
  CONCLUSIONS
  There was no evidence of an abnormally high rate of bone growth in the affected condylar region in UCH patients. Instead, the rate of bone growth appeared to be reduced in the contralateral condylar region. These PET results are in contrast to the characteristic clinical picture of UCH patients and suggest the possibility of subgroups in patients with a mandibular asymmetry caused by UCH. Furthermore, no evidence of hypervascularization of the condylar region in UCH patients was found.
authors.affiliation: Department of Oral and Maxillofacial Surgery and Oral Pathology, VU University Medical Center and Academic Center of Dentistry, Amsterdam, The Netherlands. cp.saridin@vumc.nl
authors.forename: Carrol P
authors.initials: CP
authors.lastname: Saridin
authors.forename: Pieter G H M
authors.initials: PG
authors.lastname: Raijmakers
authors.forename: Reina W
authors.initials: RW
authors.lastname: Kloet
authors.forename: Dirk B
authors.initials: DB
authors.lastname: Tuinzing
authors.forename: Alfred G
authors.initials: AG
authors.lastname: Becking
authors.forename: Adriaan A
authors.initials: AA
authors.lastname: Lammertsma
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D005146:Facial Asymmetry / Q000000981:diagnostic imaging*; D005260:Female; D005462:Fluorine Radioisotopes; D006801:Humans; D006984:Hypertrophy / Q000378:metabolism; D016014:Linear Models; D008297:Male; D008335:Mandibular Condyle / Q000098:blood supply / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology*; D010104:Oxygen Radioisotopes; D049268:Positron-Emission Tomography; D011446:Prospective Studies; D013704:Temporomandibular Joint / Q000000981:diagnostic imaging*; D055815:Young Adult
chemical_list: D005462:Fluorine Radioisotopes; D010104:Oxygen Radioisotopes