Why your nightguard might be making your TMJ worse - and what every dentist and every tooth grinder needs to know
Night guards are commonly prescribed to protect teeth from the effects of bruxism (grinding) and clenching during sleep. They help reduce pressure on the jaw joints (TMJ), prevent excessive tooth wear, and minimize strain on the surrounding muscles.
But here’s the problem: not all night guards are designed correctly. In fact, many patients find that their night guard actually worsens their symptoms instead of helping.
Why does this happen? Let’s break it down.
The Problem With Traditional Night Guards
Most dentists take an impression or digital scan of the patient’s teeth and send it to a lab to fabricate a night guard. However, the way most labs design these appliances can create significant issues—particularly for patients with TMJ problems.
How Night Guards Are Made
The lab receives the scan and opens the bite using a hinge movement at the jaw joint (condyle) level.
This rotation forces the lower jaw backward into a retruded position.
When the patient wears the night guard, their lower jaw is locked in this position, preventing natural forward movement.
Why Is This a Problem?
A retruded jaw position might not bother every patient, but for many—especially those with TMJ dysfunction—it can trigger:
Jaw pain
Clicking or popping
Headaches
Ear ringing (tinnitus)
Ear fullness or pressure
A well-designed night guard should support the TMJ, not force it into a compromised position. Unfortunately, traditional night guards can make underlying TMJ problems worse by compressing sensitive structures within the joint.
Real-World Cases: When a Night Guard Goes Wrong
Case #1: The Patient Who Developed TMJ Pain
A patient with mild tooth wear was fitted with a night guard. After wearing it, she began experiencing pain and discomfort. A Panorex X-ray revealed:
Lipping and sclerosis of the condyle
Stylohyoid ligament calcifications
Compression of the TMJ space
Instead of relieving stress, her night guard pushed the condyle further back, worsening her TMJ symptoms.
Case #2: The Patient Who Locked Her Jaw
Another patient received a splint after a routine cleaning. It seemed fine at first, but every time she wore it, her pain increased. When she told her dentist, she was advised to "keep wearing it."
The result?
Her jaw locked—she couldn’t open her mouth.
Her teeth were stuck in place, with no room for natural movement.
Even tiny jaw movements triggered muscle spasms.
This case highlights a critical mistake: Night guards should not restrict movement. Instead, they should provide stability while allowing freedom for the jaw to function properly.
What’s the Solution?
If you or your patients are experiencing discomfort with a night guard, the design may be the problem. In my next post, I’ll explain how to create a night guard that actually works—one that allows movement and prevents joint compression.
Stay tuned. A well-made night guard should protect the teeth without compromising TMJ health.