The Differences between common Oral Appliances

Dr. Michael J. Klausner
Aug 15
4 min read

Not every dental problem requires a filling, crown, or procedure in the chair. Sometimes the best treatment is something you wear, an oral appliance custom-made to fit your mouth and address a specific issue while you sleep or go about your day. These removable devices are a common, non-invasive part of modern dental care.

This brief article will introduce you to the three basic types of appliances that our doctors most commonly prescribe to our patients, as well as the rationale and other characteristics that distinguish the different types of appliances. The three most commonly prescribed appliances in our office tend to be Hard-soft nightguards, Hawley-bite planes, and Mandibular Advancement Devices (MADs).

Hard-Soft Nightguard

What Is a Hard-Soft Nightguard?

A hard-soft nightguard is a custom-made dental appliance worn over the teeth, usually the upper arch, while you sleep. It gets its name from its two-layer construction: a soft, cushioned material on the inside that contacts your teeth, laminated to a harder, more rigid outer shell. This combination is different from a fully soft guard (which can feel spongy and may actually encourage some patients to clench harder) and a fully hard guard (which some patients find less comfortable, especially early on). Your dentist takes an impression or digital scan of your teeth, and the appliance is custom fabricated to fit your bite precisely.

What does it help and when is prescribed?

It helps with clenching and grinding (also known as Bruxism), which often happens unconsciously during sleep and can lead to worn enamel, cracked teeth, jaw discomfort, and headaches. A hard-soft nightguard addresses this in several ways:

It acts as a protective barrier. The appliance sits between your upper and lower teeth, absorbing the force of grinding so your enamel doesn't wear directly against itself.
The soft inner layer improves comfort and retention. Because it molds closely to the contours of your teeth, it tends to fit snugly and feels less bulky than an all-hard appliance, which can make it easier to adjust to and wear consistently.
The hard outer shell resists wear. The rigid layer stands up well to the repeated pressure of grinding, so the appliance itself holds up over time rather than wearing through quickly.
It helps cushion the jaw joint. By providing a shock-absorbing layer between the teeth, this design can reduce the impact transmitted to the jaw joint (TMJ) and surrounding muscles, which may ease morning jaw soreness or tension headaches.
It protects restorative work. If you have crowns, bridges, veneers, or fillings, the guard helps shield them from the excess forces of nighttime grinding.

Hawley Bite Plane

What Is a Hawley Bite Plane?

A Hawley bite plane is a removable dental appliance, similar in feel to a retainer. It's typically made of a hard acrylic base that sits against the roof of your mouth (or along the inside of your lower teeth), combined with a thin metal wire that wraps around your front teeth to hold it in place. Unlike a standard retainer, a Hawley bite plane often has a small raised platform of acrylic positioned behind your upper front teeth. This platform is the key to how the appliance works.

How does it help and when it prescribed?

The Hawley bite plane also addresses clenching and grinding but does this in a few important ways:

It creates space between your back teeth. The raised platform holds your bite slightly open, so your back molars can't fully touch or grind against each other. This takes the brunt of clenching pressure off the teeth doing most of the damage.
It redistributes bite force. Instead of concentrated pressure on specific teeth, the force is spread more evenly, reducing the risk of chips, cracks, and flattened chewing surfaces.
It relaxes the jaw muscles. By changing how the jaw closes, the appliance can help ease tension in the muscles responsible for clenching, which may reduce jaw soreness and headaches over time.
It protects existing dental work. If you have crowns, veneers, or fillings, the appliance helps shield them from the excessive force that grinding can place on restorations.

Mandibular Advancement Device

What Is a Mandibular Advancement Device (MAD)?

If your dentist has recommended a mandibular advancement device (MAD), you're being introduced to an appliance that treats snoring, and in some cases mild to moderate sleep apnea, by working with your jaw position rather than your teeth alone. Here's a simple breakdown.

A mandibular advancement device is a custom-fitted oral appliance worn during sleep. It consists of two connected trays, one that fits over your upper teeth and one over your lower teeth, joined by a mechanism that gently holds your lower jaw (the mandible) in a slightly forward position compared to its natural resting spot. Some designs allow gradual, incremental adjustments so your dentist can fine-tune how far forward the jaw sits for the best results.

Unlike a nightguard, which primarily protects teeth from grinding, a MAD is designed to change the position of your jaw and tongue to keep your airway more open while you sleep.

How It Help and when is it prescribed?

Snoring and mild obstructive sleep apnea often happen because soft tissues at the back of the throat, including the base of the tongue, relax and partially block the airway during sleep. A mandibular advancement device helps by:

Repositioning the lower jaw forward. This shift pulls the tongue and surrounding soft tissue forward as well, helping keep the airway more open and reducing the vibration that causes snoring.
Increasing airway space. By preventing the jaw and tongue from falling backward during sleep, the device reduces the narrowing that leads to breathing obstructions.
Reducing snoring intensity and frequency. Many patients and their partners notice quieter, more consistent breathing during sleep once the appliance is properly fitted.
Supporting mild to moderate sleep apnea treatment. For some patients, a MAD can be an effective alternative to a CPAP machine, particularly for those who find CPAP difficult to tolerate. This is typically determined in coordination with a sleep physician following a sleep study.
Important note: If sleep apnea is suspected, a diagnosis and treatment plan should involve a sleep physician alongside your dentist. A mandibular advancement device is often prescribed collaboratively based on the results of a sleep study, and severity of apnea plays a role in whether this appliance is an appropriate treatment option.