Rapid Maxillary Expansion in Children with Nocturnal Enuresis: A Randomized Placebo-controlled trial

Abstract

Objective: To investigate whether rapid maxillary expansion (RME) is a useful treatment method for nocturnal enuresis (NE) and whether the treatment effect is due to placebo. The study also aimed to identify prognostic variables in patients responding to treatment. Materials and Methods: Thirty-eight children with therapy-resistant NE were recruited and randomized into two groups: the intervention group or placebo group. Both groups were treated with RME, but the placebo group received treatment with a sham appliance for 2 weeks before having the actual treatment. A medical history focused on micturition habits, previous treatment, heredity, and sleep disorders was taken. Daytime voided volumes and nocturnal urine production during wet nights were recorded before the intervention. Results: Of the 38 patients recruited, two dropped out as one patient was unable to take dental impressions and one refused to have the appliance fitted. There was a statistically significant reduction of wet nights after the RME treatment (P < .001). No significant reduction was found after the placebo treatment (P < .40). Eleven patients (35%) had their enuresis frequency reduced by >50%. Large voiding volume and a wide maxilla at baseline had a strong association with positive treatment outcome. Conclusions: 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. A wide maxillary width and large voiding volume at baseline seem to be positive predictors regarding response to treatment.

Influence of rapid maxillary expansion on nocturnal enuresis in children:

“…In general, the selected articles were published between 1990 and 2020 in medical and dental journals and consisted of seven non-randomized prospective studies [10][11][12][13][25][26][27] and one randomized controlled trial. 28 The sample sizes of the studies were quite variable, and only one article 13 showed control group composed of untreated patients. The patients were either in the mixed or early permanent dentitions.…”

“…[12][13][14][28][29][30] The amount of expansion obtained ranged from 4 mm 25 to 8.2 mm, 13 and the reduction of NE episodes was analyzed in both the short (6 months 28 and 8 months 25 ) and the long term (13 months, 26,27 36 months, 12,13 48 months, 10 and 120 months 11 ) by means of questionnaires, [11][12][13] interviews with patients' parents, 10,[25][26][27] registration of NE episodes on a voiding chart, 28 registration of daytime voided volumes and nocturnal urine production via weighing of diapers or sheet covers, 28 polysomnography examinations, 27 and laboratory tests of osmolality of the blood plasma to quantify the level of ADH. 12 Finally, participants of all studies were diagnosed with at least one of the following respiratory disorders: mouth breathing, 10,11,13,25,28 mixed breathing, 25 respiratory tract infections, 13 snoring, 13,26,28 adenoid hypertrophy, 10,24 amygdala hypertrophy, 10,13,25 nasal septum deviation, 25 and/or nasal obstruction. [25][26]…”

“…12 Finally, participants of all studies were diagnosed with at least one of the following respiratory disorders: mouth breathing, 10,11,13,25,28 mixed breathing, 25 respiratory tract infections, 13 snoring, 13,26,28 adenoid hypertrophy, 10,24 amygdala hypertrophy, 10,13,25 nasal septum deviation, 25 and/or nasal obstruction. [25][26][27] The methods used for diagnosis were medical examinations, [10][11][12]25,26,28 rhinomanometry, [10][11][12]25,27 acoustic rhinomanometry, 26,27 polysomnography, 26,27 cone-beam computed tomography, 12 and/or anamnestic questionnaire. 13…”

“…This may be a problem because the minimum amount of expansion necessary to accomplish the skeletal effects on the palate and nasal cavity to improve air permeability and oxygen saturation to significantly reduce episodes of NE remains unknown. 34 Only three studies 12,26,28 showed greater credibility regarding the cause and the diagnosis of NE in the sample, since the participants were submitted to previous nephrologic, neurologic, and pediatric evaluations. The participants of the other selected studies underwent only an otorhinolaryngological evaluation to diagnose respiratory disorders.…”

Rapid Maxillary Expansion and Nocturnal Enuresis in Children and Adolescents: A Systematic Review of Controlled Clinical Trials

“…2 and 3 show the risk of bias judgement for the final studies with the tools used and a justification for the grade given for each study. Two of the three CCTs [23][24][25] were assessed at moderate risk of bias and one at serious risk of bias [27], whereas the RCT [26] was assessed to be at low risk of bias.…”