There are only two main types of CPAP masks – full face masks and nasal masks. CPAP masks can be made of silicon or memory foam. The memory foam masks are much more comfortable, softer on the skin, seal much better regardless of how much you move around, and less likely to leave red marks on your face. Nasal masks include ones that wrap around the nose (traditional nasal), under the nose (nasal cradles) or up the nose (nasal pillows). They are only suitable for people who can sleep with their mouth closed all night. If you open your mouth, air will leak out and wake you up. This will feel uncomfortable and is the main cause of mouth dryness in the mornings. In our clinics, only about 20% of patients can use a nasal mask successfully. Most patients are more comfortable with a full face mask that goes around the nose and mouth. This gives patients the freedom to breathe through their nose or mouth or both which alleviates any claustrophobic feelings. Patients can even talk without any problems!
Nasal masks, which cover the nose, are often initially favourable for people starting on CPAP therapy, both by the patient concerned about their own comfort and by the clinician, because of advantages nasal masks can have over full face masks, which cover the nose and mouth. Nasal masks often perform better at lower pressures than full face masks and the smaller cushion allows for less leak than full face masks, as well as being less intrusive on the face. The main downside with nasal masks is known as ‘oral leak.’
Oral leak is the term for the mouth coming open while using a nasal mask on CPAP. With an open mouth, the pressured air going into the nose simply escapes out the mouth, creating a gust of wind that dries out the mouth, regularly wakes the user and decreases the air pressure in the upper airway, reducing the effectiveness of the therapy. There are two main ways of controlling oral leak;
(1) using medical tape to tape the lips closed, or
(2) using a chin strap which holds the chin up, reducing the likelihood of the mouth falling open.
Neither of these options are entirely reliable and are often less comfortable and effective than just switching to a full face mask.
A variant of nasal masks, nasal pillows are the smallest type of CPAP mask and sit under the nose, directing the pressured air from the CPAP machine directly into the nostrils. For people whose mouths are not falling open at night and who don’t need a particularly high pressure, nasal pillows are often the most comfortable way of experiencing CPAP. Nasal pillows have the same issue with oral leak as other nasal masks, but are also more likely to have air escaping from around the mask itself. Nasal pillows aren’t as securely strapped to the head, which is often preferable for the user, but rolling around in bed is more likely to cause the mask to become dislodged. The less securing of the nasal pillow mask compared to a nasal or full face mask also means they are less likely to be effective at high pressure settings.
Full Face Masks
Full face masks create an air-tight seal around the nose and mouth and are specifically for people who like to breathe through their mouth or whose mouth falls open at night during CPAP therapy. The majority of CPAP uses are unable to keep their mouth closed sufficiently at night, so full face masks are perhaps the most common type of CPAP mask used.
Full face masks generally require a slightly higher CPAP pressure to generate the equivalent effectiveness of a nasal mask and are more likely to let air escape out the sides of the cushion. Ensuring the mask is positioned correctly on the face and tightening the straps of the mask’s headgear is usually enough to solve the issue, but certain face shapes or the presence of thick facial hair may mean in order to achieve sufficient air seal, the mask has to be too tight and uncomfortable for long-term adherence.