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No, not everyone needs to wear a chin strap. Infact the majority of our CPAP users do not wear a chin strap. I suggest you consider if you are a mouth breather, if so a full face mask may be more comfortable for you. If your mouth drops open occasionally when you are sleeping, then a nasal mask or nasal pillows with a chin strap may work. Nasal pillows such as the Resmed Swift L/T seems to stay in place very well even for side sleepers.
Please contact us again if we can be of further help. Let us know how the pillow works for you or if you would like any more help with mask selection.
Debbie Shirley,RRT