What is the definition of the temporomandibular joint (TMJ)?
The TMJ is a synovial joint interposed between the temporal bone's glenoid fossa, articular eminence, and the mandible condylar process.
What is the mandibular fossa or glenoid fossa?
The mandibular fossa, or glenoid fossa, is the superior concave articular surface of the temporomandibular joint formed by the squamous and petrous parts of the temporal bone. It lodges the condyle of the mandible.
What is the roof of the glenoid fossa (RGF) of the TMJ?
The RGF of the temporomandibular joint is a thin plate of the temporal bone in the glenoid fossa that separates the middle cranial fossa from the TMJ.
What is the clinical significance of a thin roof of the glenoid fossa (RGF) or mandibular fossa?
The clinical significance of a thin RGF is controversial. This finding is of no clinical relevance in the asymptomatic temporomandibular joint. There is a possibility that the apparent discontinuity of the RGF is a skinny and potentially non-ossified bone challenging to be visualized because of the voxel size of the CT. Patients with temporomandibular joint disorders present a higher incidence of apparent discontinuity of the RGF in CT images.
What are the best imaging modalities to study the TMJ?
There are different imaging modalities used to evaluate the TMJ, including ultrasonography (USG), computed tomography (CT), and magnetic resonance imaging (MRI). MRI is considered the best imaging modality to diagnose TMJ abnormalities due to its superior contrast resolution.
MR images confirm a small area of an apparent cortical discontinuity in the roof of the right mandibular fossa with fluid density but no soft tissue abnormalities, masses, or signs of meningoencephalocele in the TMJs or adjacent regions. The disks are normal concerning their shape and position.
Impression: These findings are consistent with an apparent discontinuity of the roof of the right mandibular fossa.