Experimental: Intervention Arm (Soft Oral Appliance)

Parents and participants will be instructed in wearing the soft/flexible oral appliance and how to perform nasal hygiene in order to better tolerate the device. The oral appliance comes in several sizes, adapted to the age of the child; it is constructed in a soft elastomer material, in a position of slight propulsion and opening of the mandible to help clear the pharynx. It has a ramp to guide the tongue in a good position, a labial screen to stretch the labial strap and prevent the tongue from protruding between front teeth.

No_intervention: Control Arm (Nasal Hygiene)

Parents and Participants of this group will be reminded the nasal hygiene procedures (depending on the site; for example application of saline in each nostril three times a day,few simple breathing exercises), and given a diary to report daily use.