MRI evaluation of TMJ condylar angulations Poster No.: C-2272 Congress: ECR 2010 Type: Topic: Authors: Keywords: DOI: Scientific Exhibit Musculoskeletal M. Pregarz 1, C. Bodin 2 ; 1 Peschiera del Garda/IT, 2 Brescia/IT TMJ and MRI, TMJ condylar angulation, Temporo Mandibular Disorders and MR 10.1594/ecr2010/C-2272 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. www.myesr.org Page 1 of 10
Purpose Abnormal temporo-mandibular condylar angulation was observed in 655 out of 5281 TMJ examinations performed in the last 11 years. While normal condylar long axis angulation is evaluated between 10 to 30 degree referred to the coronal plane (Fig. 1), disk displacement and/or joint effusion are frequently evidenced in abnormal condylar angles. Images for this section: Fig. 1: Mandibular intercondylar angle evaluation in different Authors. Yellow: 116 (Eisenburger et Al.1999); Green: 30-34 reference the condylar long axis (Westesson et Al.1991, Kurita et Al 2003); Purple: 24-44 reference coronal plane (Westesson et Al Page 2 of 10
1987, Raustia e Pythinen 1990, Sato et Al. 1997, Sulun et Al. 2001). Mandibular condyle in blue. Page 3 of 10
Methods and Materials These 5281 temporo mandibular disorder (TMD) patients were examined with 1.5 MR unit that was changed twice during this period. Our protocol based on sagittal and coronal planes started with axial images in order to observe the intercondylar angle referred to the coronal plane. T 1, T 2 and PD images are acquired with closed mouth and sagittal T 1 and T 2 with opened mouth. Results The normal value of the temporo-mandibular condyle angle is considered between 10 to 30 degrees when referred to a repetitive and identificable anatomical structure as external auditory meatus or the caroticous canal. An over 30 degrees angle is considered as a "vertical rotation" and an under 10 degrees angle as an "horizontal rotation". Condyle rotations were found in 655 out of 5281 patient: 115 were monolateral and 540 bilateral.; horizontal rotation occurs in 277/655 pts (42,3%) and vertical rotation in 378/655 pts (57,7%). The horizontal rotation was associated with joint effusion in 92 TMJ, with disk displacement (DD) in 174 TMJ [132 without reduction (DDWR) and 42 with reduction (DDR)] while 52 horizontal condyle rotations did not presented any DD. In the vertical rotation group 114 TMJ were associated with joint effusion, 209 TMJ with DD (127 DDWR and 82 DDR) when 101 TMJ of this group were without DD (Fig.1). Images for this section: Page 4 of 10
Fig. 1: Diagram of TMD examinations Page 5 of 10
Conclusion Abnormal rotation of mandibular condyle was evidenced in 12,4% of our TMJ examinations. The horizontal rotation associated with DDWR was statistically significant (p<0,001). No statistical association were found for DDR or joint effusion. Subsequently abnormal long axis rotation may be considered as an induced factor of dysfunction of the stomatognatic system. At the normal TMJ protocol we suggest to add an axial sequence to evaluate the condyle angle value (Figg. 1-3). Images for this section: Fig. 1: Axial T1 MR image, normal condylar angulation (10-30 ). Page 6 of 10
Fig. 2: Axial T1 MR image, "vertical rotation" when >30. Page 7 of 10
Fig. 3: Axial T1 MR image, "horizontal rotation" when < 10. On the right side angle inversion is seen because of condylar external rotation (no fracture or trauma in clinical history). Page 8 of 10
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armed@tin.it C. Bodin, Dental School, University of Brescia, Brescia, ITALY bodinch@libero.it Page 10 of 10