Radiographic examinations of the temporomandibular joint

Dobó-Nagy, CsabaSemmelweis University

Knowledge required by clinicians

Anatomy Available investigations

Clinical indications How each investigation is performed

position open or closed

Limitations Pathological conditions

Anatomical section of a normal TMJ

condyle

disk

Glenoid fossaGlenoid fossa

tubercle tubercle (articular (articular eminence)eminence)

lateral pterygoid muscle

Skull base model

AA PP

LL RR

Visualization of the TMJ

Main radiographyc projections of the TMJ

TrCran

TrPhar

TrOrb

SMV

RevTowne

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

Soft tissue abnormalities Effusion Small and localised bony defects One aspect of the joint (except for

tomography)

Main pathological signs of TMJ

AA BBBB CCCC

DDDD EEEE FFFF

GGGG HHHH IIII

Adaptive response

Osteophyte formation

Fracture

osteochondroma

Dislocaition of disk without reduction

Diagnostic informations of MR

Disk displacement The integrity of the disk and its

soft tissue attachments Effusion (T2-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

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

Radio-grapic modalities

anatomy pathology adaptation

hard soft hard soft hard soft

panoramic

traditional

CBCT/CT

MRI

Suggested hierarchy of imaging modalities in TMJ disease

panoramic MRI

tomography

CBCT, CT

soft tissue changes

bone changes

Primary examination:

•dysfunction

•organic changes

•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