Introduction and objective:
The orthodontic technique rapid maxillary expansion (RME) has been reported to have a potentially curative effect on nocturnal enuresis (NE). The mechanism behind this is unknown but could possibly be due to placebo and/or effects on respiration during sleep. The aim of our study was to investigate whether RME is a useful therapy for NE and if the treatment effect is due to placebo. Our study also aims to identify prognostic variables and evaluate the effect RME may have on respiration during sleep in enuretic children.
38 children with therapy-resistant NE were recruited and randomized into two groups, either the intervention group or the placebo group. Both groups were treated with RME, but the placebo group received treatment with a sham appliance for two weeks before having the actual treatment. A medical history focused on micturition habits, previous treatment, heredity and sleep disorders was taken. Cardiorespiratory polygraphic sleep registrations were carried out 3 times; at baseline (T0), during RME (T1) and six months after RME (T6).
There was a statistically significant reduction of wet nights after the RME treatment (p50%. Large voided volume and a wide maxilla at baseline had a strong association with the favorable treatment outcome. There was a significant difference in sleep efficiency between the three measures. (P=0.001) The mean hypopnea index was 0.3, 0.5 and 0.2 at T0, T1 and T6 respectively. These changes were statistically significant. (P=0.005) The majority of the children did not have SDB in addition to their nocturnal enuresis.
RME has a modest effect on children with therapy-resistant NE. The treatment outcome does not seem to be due to a placebo effect of the appliance.