At SleepWise Clinic we are often asked “What is the best oral appliance to treat snoring and obstructive sleep apnoea?”
This article will discuss the basis for choosing an appliance and then review some of the commonly used snoring devices in Australia.
Oral appliances are now recognised by researchers and experts in the field as the best available treatment, and along with the CPAP machine, one of the two treatments for sleep apnoea.
Not all appliances are the same and it is important that a dentist chooses from an array that has demonstrated effectiveness and safety based on published, scientific studies in refereed journals. The use of appliances lacking supporting evidence of effectiveness and safety cannot be justified.
The appliance must comply with the definition of an oral appliance as outlined by the published expert consensus of the American Academy of Dental Sleep Medicine (AADSM)1. This is the standard even when treating sleep apnea in Australia.
The appliance design should also be of minimal dimensions, and result in minimal side effects.
The type of material
Traditionally appliances have been made from acrylic resin, the same material that dentures are made from. While acrylic resin has served the profession well, it is not without problems. The material is brittle, prone to fracture, and consequently needs to be relatively thick. There has been a revolution in the materials used for appliances with the advent of 3D printed nylon.
3D printed nylon
3D printed nylon brings in a new era which is rendering the traditional acrylic resin obsolete for the manufacture of appliances. Appliances made from nylon can be made down to a thickness of 0.5mm, yet still be unbreakable in the mouth. This is of the utmost importance given that comfort, compliance and longevity are regarded as the key factors for successful outcomes.
Selecting the right appliance for each individual patient
It is important that a dentist can choose from a range of appliances in order to select the one most appropriate for the individual patient.The choice of appliance may depend on factors such as number and configuration of teeth, the relationship between the upper and lower arch, the presence and degree of bruxism (clenching and grinding), the presence of TMJ dysfunction and the amount of intra oral space.
Review of 6 Custom-Made Oral Appliances
The appliances reviewed here have a similar level of efficacy, however they vary in comfort, longevity and the potential to cause side effects.
Apart from the materials used, a significant point of difference between the appliances is whether there is a solid connection between the upper and lower parts. When the upper and lower parts are connected there is the potential to cause more side effects than if the parts are not connected, and can move independently.
The following factors were assessed for each appliance:
Appliances are subjected to the forces of clenching and grinding, and it is extremely important that they are sufficiently strong so they don’t break while in use. Traditional materials, such as acrylic resin, are prone to fracture and the appliance needs to be relatively thick
As patients will use their appliance up to 8 hours per night over the mid to longer term, a focus on comfort is key for achieving successful outcomes. Comfort can vary considerably depending on the type of material, and the design of the appliance.
Adjusting the appliance is crucial in finding the optimal position of the jaw that eliminates the snoring and all the symptoms of sleep apnoea. While it is critical that an appliance has inbuilt adjustability (as not all do) the ease and ability to make fine adjustments can vary considerably.
The following table outlines and reviews the most common appliances, also known as sleep apnea mouth guards, that dentists are currently providing for their patients in Australia.
3D Nylon Dorsal
The dorsal design is the only appliance in which the upper and lower parts are not connected and allows jaw opening and closing, sipping water and speaking. Nylon construction allows optimal strength in thin sections.
3D Nylon Panthera
Manufactured in Canada from 3D printed nylon, the upper and lower parts are connected with exchangeable side connectors for titration.
Acrylic Somnodent – classic and flex
A dorsal design appliance, with the advantage of upper and lower parts not connected. Construction is from hard acrylic, or a soft-hard combination, making these appliances thicker than those made from nylon and subsequently more prone to fracture.
An Australian designed appliance in which the upper and lower parts are connected by an anterior adjustable hook attached to a plate in the lower. This appliance prevents the jaw from dropping during sleep and can be a useful feature for a subgroup of patients.
While the stainless steel of the anterior mechanism is strong, the acrylic construction of the body of the appliance is prone to fracture. The anterior mechanism can prevent desirable anterior tongue movement and be an irritant for many patients. It is generally regarded that there is a greater potential for bite changes with this appliance.
Made from 3D printed nylon, this appliance has flexible side connectors identical to that of the EMA appliance. There is an anterior air vent which may be useful for patients with nasal obstruction. The addition of the air vent adds to the thickness and vertical height, making the appliance more obtrusive than others.
This appliance is from the USA and is generally made from a hard/soft laminate material which has limited longevity and is prone to fracture and staining. The upper and lower parts are connected with exchangeable elastic side connectors for titration. The side connectors stretch, thereby not maintaining the mandibular position thus requiring regular changing.
By Dr Harry Ball
BDSc LDS (Melb) M Counselling (Latrobe) Grad Dip Counselling & HS (Latrobe)
Co Chair Dental Sleep Council, Australasian Sleep Association