A 40-year-old woman was referred to the department of temporomandibular joint at West China Hospital of Stomatology, Sichuan University with a complaint of uncomfortable and chronic pain in both sides of preauricular zone lasting for 6 months, which was aggravated by palpation and mastication. There was no history of trauma or any other event that contributed to the onset of symptoms and the past medical history was unremarkable, Family history was unremarkable, Relevant social history was unremarkable. The patient was treated previously with nonsteroidal anti-inflammatory drugs and physiotherapy, which seemed to have little effect.
Physical examination showed that the patient exhibited the facial asymmetry with slight diffuse swelling of bilateral preauricular region and pain, which would be aggravated by palpation and mastication. The maximal mouth opening was 32 mm and the midline of the mandible deviated slightly to the right, while there was no malocclusion intraorally.
Radiologic examination included X-ray, CBCT and MRI. While panoramic radiograph suggested the calcified tissue was anterior superior to the left mandibular condyle, CBCT showed calcification and displacement of the left articular disk and flattening of the head of left mandibular condyle (Fig.1).
MRI further revealed forward displaced crumpled disc without reduction of the left joint, whose density was close to the condyle, and there was perforation in the bilaminar zone (Fig.2). Sagittal MRI also showed arthroedema in the right joint and disc displacement without reduction (Fig.3).
After these examinations, the patient was diagnosed as late-stage left TMJ osteoarthritis complicated by calcification of left articular disk; right TMJ arthroedema and bilateral disc displacement without reduction.
The patient underwent the removal of the left disc and condyle and simultaneous reconstruction with costochondral bone and temporal fascia as well as right disk reduction with anchoring screw (Fig.4).
The resected disk and condyle were sent for examinations including immunochemistry, scanning electron microscope, energy-dispersive X-ray spectrometry studies (Fig. 5-7). CBCT and MRI were repeated 2 weeks after operation. After surgery, the patient's perceived mouth opening was not significantly limited, bilateral joint pain was relieved. The patient was able to open her mouth to 37mm with slight deviation to the right side and her pain was recorded as 0 (VAS) 6 months later. The disease had not recurred during the follow-up of 12 months.
A structured literature review of calcification of disk in temporomandibular joint was conducted using MEDLINE to search related English papers from 1952 to present.
Table 1. Calcification of the articular disk (literature review)
First author
(year)
|
Morphology in microscopy
|
Crystal identified
|
Organic complications
|
etiopathogenesis
|
Mechanism explained
|
Piacentini
(1995)
|
Endodiscal radiopaque area
|
hydroxyapatite
|
Endoarticular loose bodies
|
Displastic alterations of disk
|
Chronic inflammatory
|
Marchetti
(1997)
|
bone-like tissue
|
hydroxyapatite
|
Vascularization
around alcification
|
Metaplastic modification disk tissue
|
Excessive functional stress
|
Bernasconi
(1997)
|
Calcified material depositstissue
|
|
Hyperplasia of synovial tissuearound
|
Synovial ceells migration and modificationmodification of
|
Articular over-loadingfunctional
|
Jibiki
(1999)
|
intradiscal bone formation
|
CPPD and apatite
|
disk perforationcalcification
|
endodiscal calcification and degenerationdisk tissue
|
mechanical damage
stress
|
Koyama (2001)
|
|
|
displaced disk and synovial chondromatosis Hyperplasia
|
|
|