Temporomandibular Joint Radiography 牙科放射線學(2) Temporomandibular Joint Radiography 顳顎關節放射線攝影術 陳玉昆副教授: 高雄醫學大學 口腔病理科 07-3121101~2755 yukkwa@kmu.edu.tw

學 習 目 標 The normal anatomy of the TMJ What investigations are available Common pathological conditions that can affect the joints References 1. Eric Whaites: Essentials of dental radiography & radiology 3rd edition, Chapter 29, p. 371-388 2. Eric Whaites: Essentials of dental radiography & radiology 1st edition, Chapter 28, p. 297-323. 3. Rosenberg et al, Aust Dent J 1999;44:106 4. Kaohsiung Medical University, Oral Pathology Department

Subtopics The normal anatomy of the TMJ What investigations are available Common pathological conditions that can affect the joints

Normal Anatomy (Hard tissue) (Soft tissue) (Hard tissue) (Soft tissue) Condyle head Disc/meniscus Glenoid fossa Lateral pterygoid attachment Upper joint space Lower joint space Ext auditory meatus Ref. 1

Lateral Anterior Normal anatomy - Dry skull Base Ref. 1

Rotatory and translatory movements of condyle during normal mouth opening Rest position Mouth closed Primary rotation opened Translation initially widely Secondary Ref. 1

What investigations are available (1) The clinical indications How each investigation is performed, i.e. how the patient is positioned in relation to the film and X-ray tubehead, and whether the patient’s mouth needs to be open or closed

What investigations are available (2) What information each investigation The limitations and shortcomings of each investigation

Investigations Conventional radiographic projections Other techniques and investigations Transcranial Transpharyngeal Panoramic Reverse Town’s Transorbital Tomography, linear

Summary of different parts of TMJ shown by the conventional projections Ref. 1

Transcranial Main indications TMJ pain dysfunction syndrome – pain, clicking and limitation in opening To investigate the size & position of the disc (joint space) To investigate range of movement in the joints Main indications

Transcranial Centric occlusion Mouth close Mouth open <N.B.>The radiological term joint space: radiolucent zone between condylar head & glenoid fossa, which includes discs & upper & lower anatomical joint spaces Mouth close Right Mouth open Right Ref. 1

Diagnostic information Closed view The size of the joint space – provide indirect information about the position and shape of the disc The position of the head of the condyle within the fossa The shape and conditions of the glenoid fossa & articular eminence (on the lateral aspect only) The shape of the head of the condyle & the condition of the articular surface (on the lateral aspect only) A comparison of both sides Transcranial Open view The range and type of movement of the condyle A comparison of the degree of movement on both sides

Transpharyngeal Main indications TMJ pain dysfunction syndrome To investigate the presence of joint disease, particularly osteoarthritis and rheumatoid arthritis To investigate pathological conditions affecting the condylar head, including cysts or tumors Fractures of the neck and head of the condyle

Diagnostic information Transpharyngeal Diagnostic information The shape of the head of condyle and condition of the articular surface from lateral aspect A comparison of both condylar heads Ref. 1

Dental panoramic tomograph Main indications Main indications TMJ pain dysfunction syndrome To investigate disease within the joint To investigate pathological conditions affecting the condylar heads Fractures of the condylar head or neck Condylar hypo/hyperplasia Diagnostic information The shape of the condylar head and condition of the articular surface from lateral aspect A direct comparison of both condylar heads

Dental panoramic tomograph Right close Right open Left open Left close Transcranial view taken from panoramic machine Ref. 4

Reverse Towne’s Main indications To investigate the articular surface of the condyles and disease within the joint Fractures of the condylar heads and necks Condylar hypo/hyperplasia Main indications Mouth open Ref. 1

Diagnostic information Reverse Towne’s Diagnostic information The shape of the condylar heads and condition of the articular surfaces from the posterior aspect A direct comparsion of both condyles Ref. 1

Transorbital (Zimmer’s view) Main indications To investigate the articular surface of the condyle and disease within the joint High fractures of the condylar neck to show medio-lateral displacement This view is rarely used because of the risk of damage to the lens of eye from radiation. However, it provides an AP view of the condylar head- an aspect not shown by other radiographs Mouth open Ref. 2

Diagnostic information Transorbital The shape of the condylar head and neck from the anterior aspect The condition of the articular surface from the anterior aspect Ref. 2

Tomography Main indications Full assessment of the whole of the joint to determine the presence and site of any bone disease or abnormality To investigate the condyle and articular fossa when the patient is unable to open the mouth Assessment of fractures of the articular fossa and intracapsular fractures

Tomography 15o 20o 25o 30o Lateral Anterior Ref. 1

Diagnostic information Tomography Diagnostic information The size of the joint space The position of the head of the condyle within the fossa The shape of the head of the condyle and condition of the articular surface including the medial and lateral aspects The shape and condition of the articular fossa and eminence Information on all aspects of the joints The positions and orientation of the fracture fragments

Other techniques & investigations 下列何者是AP view為： A. Panoramic radiography B. Transcranial projection C. Transorbital D. Modified Town’s view Arthrography Computed tomography Magnetic resonance imaging Artheroscopy Main indications Diagnostic information

Main contraindications Arthrography Main indications Longstanding TMJ pain dysfunction unresponsive to simple treatments Persistent history of locking Limited opening of unknown etiology Main contraindications Acute joint infection Allergy to iodine or contrast medium

Diagnostic information Arthrography Diagnostic information Dynamic information on the position of the joint components and disc as they move in relation to one another Static images of the joint components with the mouth closed and with the mouth open. Any anterior or anteromedial displacement of the disc can be observed The integrity of the disc, i.e. any perforations Note: Outline the lower joint space usually provides more useful information on the disc Ref. 1

Computed tomography Main indications Diagnostic information It provides sectional or slice images of the joint It can produce images of the hard and soft tissues in the joint, including the disc, in different planes Diagnostic information The shape of the condyle and the condition of the articular surface The condition of the glenoid fossa and eminence The position and shape of the disc The integrity of the disc and its soft tissue attachments The nature of any condylar head disease

Computed tomography Ref. 4

Magnetic resonance imaging Main indications When diagnosis of internal derangements is in doubt As a preoperative assessment before disc surgery Anterior displaced disc Condylar head Ref. 4

Arthroscopy Main indications It gives direct visualization of the TMJ and allows certain interventional procedures to be performed, including Washing out the joint with saline Introduction of steroids directly into the joint Division of adhesions Removal of loose bodies from within the joint Arthroscopy is considered as the last line of investigation before full surgical exploration of the joint is carried

Arthroscopy Upper joint space Lower joint space Disc Prolene suture Yeates drain External auditory meatus Ref. 3

Disc Adhesion Arthroscopy Fibrillation Disc Ref. 4

Main pathological conditions affecting the TMJ TMJ pain dysfunction syndrome Internal derangements Osteoarthritis Juvenile rheumatoid arthritis (Still’s disease) Ankylosis Tumors Fractures Developmental anomalies

Main pathological conditions affecting the TMJ A multilocular radiolucency; (B), (C) Surgical specimen; (D) Costochondral graft; (E) Histological examination: bony trabeculae entrapped by multiple blood vessels 最可能的診斷為： A. Ameloblastoma B. Squamous cell carcinoma C. Hemangioma D. Central giant cell granuloma

Summaries Knowing: The normal anatomy of the TMJ What investigations are available Common pathological conditions that can affect the joints

remember these three points The End Revision Have you already remember these three points (red, yellow & green)? What are the key points of this lecture?