Radiographic examinations of the temporomandibular joint DobNagy Csaba

Radiographic examinations of the temporomandibular joint Dobó-Nagy, Csaba Semmelweis University

Knowledge required by clinicians n n Anatomy Available investigations n n Clinical indications How each investigation is performed n n position open or closed Limitations Pathological conditions

Anatomical section of a normal TMJ disk Glenoid fossa tubercle (articular eminence) condyle lateral pterygoid muscle

Skull base model A L P R

Visualization of the TMJ

Main radiographyc projections of the TMJ Tr. Cran Tr. Orb Tr. Phar Rev. Towne SMV

Transcranial projection

Reverse Towne’s

Transorbital

Transpharyngeal (Parma)

Dental panoramic tomograph

Condylar silhouette

Projection of panoramic tomography

Double lateral view of TMJ

SMV

Corrected tomography

Limitations of routin radiographic projections n n Soft tissue abnormalities Effusion Small and localised bony defects One aspect of the joint (except for tomography)

Main pathological signs of TMJ A B C D E F G H I

Adaptive response

Osteophyte formation

Fracture

osteochondroma

Dislocaition of disk without reduction

Diagnostic informations of MR n n n Disk displacement The integrity of the disk and its soft tissue attachments Effusion (T 2 -weighted image) Integrity of the articular surface Research (gold standard)

CT coronal view

CT sagittal view

CBCT imaging of a normal TMJ

CBCT examination of arthritis

Osteophyte

Ankylosis

Diagnostic informations of CT n n n The shape of the bony compartments Information on all aspects of the joint The condition of the articular surface The size of the joint space Integrity of the disk and soft tissue attachements

Size of TMJ space and soft tissue changes

Diagnostic informations by modalities Radiograpic modalities panoramic traditional CBCT/CT MRI anatomy hard soft pathology hard soft adaptation hard soft

Suggested hierarchy of imaging modalities in TMJ disease soft tissue changes panoramic MRI bone changes tomography Primary examination: • dysfunction • organic changes CBCT, CT • failed treatment

Summary of views of main projections projection area of joint shown Transcranial lateral aspect Transpharyngeal lateral aspect Dental panoramic lateral aspect Reverse Towne’s posterior view Transorbital anterior view