A simple home test to differentiate habitual from pathological mouth breathing

Mouth breathing (MB) is defined as breathing through the mouth alone or the mouth and the nose for more than six months. Unfortunately, after managing its mechanical causes, MB may continue due to habit, obscuring the results of surgical correction of nasal breathing and misleading to unnecessary or aggressive maneuvers.

to develop and evaluate a new test to define children of habitual MB.

Design: a prospective observational study conducted from May 2022 to February 2023.

multicenter; outpatient university clinics and a private ENT center.

577 children aged 2-12 years and complaining of MB during sleep (±daytime) for ≥6 months were assessed for eligibility, 340 were excluded due to a lack of inclusion criteria, 29 declined or discontinued participation, and 208 were enrolled. Of these, 180 gave reliable data.

After about 1 h of the child's sleep, the parent applies one warmed hand to close the child's open mouth recording his awakeness time (AT) for a maximum of 3 min for three nights. On the next visit, the child's examination started for obstruction causes, including endoscopy, and the test results were collected.

The AT was compared to examination results aiming to find a significant diagnostic relation. Children with no abnormality in the clinical and endoscopic examination were considered habitual mouth breathers.

Among 94 males and 86 females aged 2-12 years, MB duration ranged from 6 to 42 months, with a mean of 15.9. The home test results were presented by the mean AT in seconds. The awakeness time (AT) could discriminate patients' abnormalities at a cut-off level of <133 s, with 98.5% sensitivity and 89.7% specificity. Results <133 s are considered positive. Positive results mean the presence of a cause of obstruction. Negative results suggest no reason could be detected by endoscope or clinical examination. True positive children were 120 (66.7%), and 12 (6.7%) were false positive. True negative children were 43 (23.9%), and 5 (2.8%) were false negative.

Test results ≥133 s are associated with habitual MB. We recommend the test for the initial assessment of night MB.