Complications and Outcomes of TMJ Total Joint Replacement

Introduction to Complications

Facial nerve weakness is the most common long-term complication associated with temporomandibular joint (TMJ) total joint replacement, with manifestations ranging from paresis and paralysis (7.8%) to sensory alterations (1.8%) 1, 2

The proximity of the surgical site to vital structures and prolonged tissue retraction during surgery can stretch and temporarily impact nerve function 1, 2
Transient weakness of the temporal, buccal, and marginal mandibular branches of the facial nerve is commonly observed immediately post-operatively 2
Most cases resolve within six months, though a minority of patients experience persistent paralysis of the temporal branch requiring unilateral brow lift 2
TMJ replacement operations account for 40% of facial nerve injuries in oral and maxillofacial surgeries 2

Revision TMJ replacement procedures increase the risk of temporary facial nerve injury 2
Bilateral surgery is a risk factor for facial nerve injury 2
Multiple previous open TMJ procedures increase the risk of facial nerve injury 2

Routine identification of facial nerve branches in the operative field is essential to minimize the risk of facial nerve complications 2
Careful dissection along fascial planes helps prevent nerve injury 2
Extreme caution during nerve dissection, particularly in revision surgeries where scar tissue may obscure visualization, is necessary 2
The preauricular approach provides better access with reduced risk of facial nerve injury 2
Low-intensity laser therapy, particularly when augmented with vitamin complex medication, has shown efficacy in mitigating nerve injury effects 2

Implant instability and loosening of screws are significant long-term complications 1, 2
Relapse of TMJ ankylosis is a potential long-term complication 1, 2
Unresolved functional deficits can occur as a long-term complication 1, 2
Infection is a possible complication, though with a relatively low incidence at 0.7% 3
Metal hypersensitivity affects approximately 10-15% of patients with implants 4, 5

Significant improvements in maximum interincisal opening (MIO) and mandibular function can be expected 6

Patients should be counseled about the risk of facial nerve weakness as the most common long-term complication 2
Regular long-term follow-up is essential to monitor for complications, as some may develop years after surgery 3
Particular attention should be paid to patients with risk factors such as multiple previous surgeries 2
Custom TMJR devices are recommended as the standard of care in cases with significant anatomical deviations or substantial changes in mandibular position 7