Gnathology: bruxism treatment and night guards

The teeth, chewing muscles and temporomandibular joints (TMJ, the joints in front of the ears that move the lower jaw) work as one system. When the balance is disturbed, enamel wears down, the joint clicks, facial muscles feel tired and headaches appear in the morning. Gnathology dentistry is the area of dentistry that studies how the jaw system works in motion. At UKRMED it covers bite and joint assessment and custom splints and deprogrammers (devices that relax the chewing muscles).

Photo: Lee Haywood, Wikimedia Commons, CC BY-SA 2.0

What a gnathologist does

A gnathologist is a dentist who looks not at a single tooth but at how the teeth meet, how the jaw moves and how the joints are loaded. They find out why teeth are wearing down and where clicking or pain comes from, then plan treatment: a splint, bite correction, restoring worn teeth or, in complex cases, referral to a maxillofacial surgeon.

When to see a specialist

• you or your partner notice that you grind your teeth at night;
• your jaw muscles, temples or neck ache in the morning;
• your teeth are worn, chipped, cracked or sensitive;
• your jaw clicks, crunches or opens with a jolt;
• it is hard to open your mouth wide;
• your bite feels "wrong" after new fillings or crowns.

What bruxism is

Bruxism is involuntary clenching or grinding of the teeth. People usually do not notice night-time grinding: they learn about it from a partner or from marks on their teeth. Common factors include stress, sleep problems, some medicines, coffee and alcohol. Over time bruxism wears enamel, breaks fillings and crowns and overloads the joints.

How a night guard works

An occlusal splint is a custom plate of hard acrylic worn over the teeth at night. It separates the upper and lower teeth, so they wear against the acrylic rather than each other, and spreads the load on muscles and joints.

A Cochrane review (a systematic review by the international Cochrane organisation, which assesses how well treatments work) notes that there is not enough evidence that a splint on its own stops bruxism. That is why a splint is seen as protection for teeth and restorations and as part of wider treatment, not the only remedy. The causes, such as stress or poor sleep, are addressed separately.

Night guards are made at two levels of complexity: a simpler one protects the teeth, a more complex one is also shaped to your bite and jaw movements.

Deprogrammer and Aqua Splint

A deprogrammer is a small device on the front teeth that keeps the back teeth apart while worn. The muscles relax and the gnathologist can find the correct jaw position, for example before prosthetics or bite correction. It can be made chairside (clinical) or in the laboratory (by a dental technician from an impression).

Aqua Splint is a splint with fluid-filled pads that spread pressure evenly between the teeth. It is used for TMJ disorders to relieve muscle tension.

Diagnostics

The gnathologist examines your teeth and bite, checks jaw movements and feels the chewing muscles and joints. To see the bone structure of the joint, a TMJ CT scan is ordered. If changes in the joint are significant and conservative treatment (splints, medication, physiotherapy - without surgery) does not help, surgical options such as TMJ arthroplasty (surgery that restores the shape and movement of the joint) are considered.

After the splint

A splint protects the teeth but does not bring back lost enamel. Worn and chipped teeth are restored with fillings and restorations or crowns, and a wrong bite is corrected with braces or aligners. This spreads the load evenly and stops the problem coming back.

Prices for splints and gnathology devices

Sources

1. Macedo C. R., Silva A. B., Machado M. A. et al. Occlusal splints for treating sleep bruxism (tooth grinding). Cochrane Database Syst Rev, 2007. https://doi.org/10.1002/14651858.CD005514.pub2
2. NHS. Teeth grinding (bruxism). https://www.nhs.uk/conditions/teeth-grinding/