TY - JOUR
T1 - Osseous and muscular changes after vertical ramus osteotomy. A magnetic resonance imaging study
AU - Westesson, Per Lennart
AU - Dahlberg, Gunnar
AU - Hansson, Lars Göran
AU - Eriksson, Lars
AU - Ketonen, Leena
N1 - Funding Information:
Supported by the Torsten and Ragnar Sijderberg Foundation, Stockholm, Sweden. BDepartments of Radiology and Clinical Dentistry, University of Rochester School of Medicine and Dentistrv. _. and Denartment of Orthodontics, Eastman Dental Center, Rochester. . bDepartment of Oral Surgery, University Hospital of Lund. CSection of Oral Radiology, Department of Radiology, University Hospital of Lund. dDepartment of Radiology, University of Rochester School of Medicine and Dentistry.
PY - 1991/8
Y1 - 1991/8
N2 - Magnetic resonance (MR) imaging was performed about 2 years after vertical ramus osteotomy of 10 patients to study changes in the mandibular condyle, cortical and cancellous bone of the proximal fragment, and muscles of mastication. MR imaging observations of the surgically treated patients were compared with findings in 10 asymptomatic untreated control subjects. The results showed that the MR appearance of bone marrow of the mandibular condyle was normal in all patients and in all control subjects. No MR evidence of avascular necrosis of the mandibular condyle was found. MR imaging artifacts from microscopic metallic particles were seen in all surgically treated regions. Thickening of the buccal and lingual cortical bone with narrowing of the bone marrow space was seen bilaterally in eight patients and unilaterally in two patients. Slight medial tipping of the mandibular condyle was seen unilaterally in two patients. Atrophic changes with decreased muscle volume and fatty replacement of muscle tissue was seen unilaterally in eight patients. None of these alterations were seen in the control subjects. MR imaging appears to be an excellent method to study morphologic changes of the muscles of mastication and osseous fragments after orthognathic surgery of the mandible. Thickening of the cortical bone and narrowing of the bone marrow space of the proximal fragment was frequently seen after vertical ramus osteotomy of the mandible and most likely represents remodeling associated with normal healing.
AB - Magnetic resonance (MR) imaging was performed about 2 years after vertical ramus osteotomy of 10 patients to study changes in the mandibular condyle, cortical and cancellous bone of the proximal fragment, and muscles of mastication. MR imaging observations of the surgically treated patients were compared with findings in 10 asymptomatic untreated control subjects. The results showed that the MR appearance of bone marrow of the mandibular condyle was normal in all patients and in all control subjects. No MR evidence of avascular necrosis of the mandibular condyle was found. MR imaging artifacts from microscopic metallic particles were seen in all surgically treated regions. Thickening of the buccal and lingual cortical bone with narrowing of the bone marrow space was seen bilaterally in eight patients and unilaterally in two patients. Slight medial tipping of the mandibular condyle was seen unilaterally in two patients. Atrophic changes with decreased muscle volume and fatty replacement of muscle tissue was seen unilaterally in eight patients. None of these alterations were seen in the control subjects. MR imaging appears to be an excellent method to study morphologic changes of the muscles of mastication and osseous fragments after orthognathic surgery of the mandible. Thickening of the cortical bone and narrowing of the bone marrow space of the proximal fragment was frequently seen after vertical ramus osteotomy of the mandible and most likely represents remodeling associated with normal healing.
UR - http://www.scopus.com/inward/record.url?scp=0025991260&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0025991260&partnerID=8YFLogxK
U2 - 10.1016/0030-4220(91)90152-3
DO - 10.1016/0030-4220(91)90152-3
M3 - Article
C2 - 1923390
AN - SCOPUS:0025991260
SN - 0030-4220
VL - 72
SP - 139
EP - 145
JO - Oral Surgery, Oral Medicine, Oral Pathology
JF - Oral Surgery, Oral Medicine, Oral Pathology
IS - 2
ER -