title: The effect of rapid palatal expansion on sleep bruxism in children.
abstract: BACKGROUND
  Sleep bruxism (SB) is a movement described as an involuntary mastication movement during sleep, also defined as rhythmic masticatory muscle activity (RMMA). It is observed in 2-40 % of the pediatric population. A link was suggested between respiratory events and RMMA. Rapid palatal expansion (RPE) is an effective orthopedic treatment for correcting maxillary transverse deficiency and sleep-disordered breathing (SDB) in children. The aim was to evaluate the possible reduction of SB after rapid palatal expansion (RPE) therapy.
  
  
  METHODS
  A total of 32 patients (8-14 years old; 22 girls and 10 boys) received an orthodontic treatment for transverse maxillary deficiency (5 mm or more) at the orthodontics department of the Université de Montréal. They underwent an ambulatory polysomnography (PSG) before, after expansion with the expander, and at the end of the study without the expander. They were classified into three subgroups based on sleep electromyography (EMG) data.
  
  
  RESULTS
  Total sleep time and stage NREM 3 presented significant differences between the types of appliances. Moreover, there was a time effect observed for total sleep time, sleep cycles, stage NREM 2, and stage REM, while only a trend suggested for stage NREM 3. Significant differences were observed between subgroups for both RMMA episodes and burst indexes, similarly, for the oxygen desaturation index (ODI). A total of 50 % of the patients were classified as responders when RMMA episodes index decreased by more than 25 % when comparing treatment efficacy at baseline night.
  
  
  CONCLUSIONS
  Most bruxers (65 %) reduced their RMMA episode index after expansion, but sleep and respiratory variables remained unchanged.
authors: Faculté de Médecine Dentaire, Université de Montréal, CP 6128 succ. Centre-ville, Montreal, QC, H3C 3J7, Canada.|Faculté de Médecine Dentaire, Université de Laval, 2420 rue de la Terrasse, Pavillon Médcine Dentaire, Quebec (Que.), G1V 0A6, Canada.
authors: Audrey
authors: A
authors: Bellerive
authors: Faculté de Médecine Dentaire, Université de Montréal, CP 6128 succ. Centre-ville, Montreal, QC, H3C 3J7, Canada.
authors: Andrée
authors: A
authors: Montpetit
authors: Faculté de Médecine Dentaire, Université de Montréal, CP 6128 succ. Centre-ville, Montreal, QC, H3C 3J7, Canada.
authors: Hicham
authors: H
authors: El-Khatib
authors: Faculté de Médecine Dentaire, Université de Montréal, CP 6128 succ. Centre-ville, Montreal, QC, H3C 3J7, Canada.
authors: Maria Clotilde
authors: MC
authors: Carra
authors: Faculté de Médecine Dentaire, Université de Montréal, CP 6128 succ. Centre-ville, Montreal, QC, H3C 3J7, Canada.
authors: Claude
authors: C
authors: Remise
authors: Centre de Recherche du CHU Sainte-Justine, 3175, Chemine de la Côte-Sainte-Catherine, Montrea (Que.), H3T 1C5, Montreal, Canada.
authors: Eve
authors: E
authors: Desplats
authors: Faculté de Médecine Dentaire, Université de Montréal, CP 6128 succ. Centre-ville, Montreal, QC, H3C 3J7, Canada. nelly.huynh@umontreal.ca.|Centre de Recherche du CHU Sainte-Justine, 3175, Chemine de la Côte-Sainte-Catherine, Montrea (Que.), H3T 1C5, Montreal, Canada. nelly.huynh@umontreal.ca.
authors: Nelly
authors: N
authors: Huynh
mesh_terms: D000293:Adolescent; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D017063:Outcome Assessment, Health Care; D010155:Palatal Expansion Technique; D017286:Polysomnography; D020181:Sleep Apnea, Obstructive / Q000209:etiology / Q000628:therapy*; D020186:Sleep Bruxism / Q000150:complications / Q000628:therapy*
keywords: Children; Maxillary deficiency; Polysomnography; Rapid palatal expansion; Rhythmic masticatory muscle activity; Sleep bruxism