title: The effect of adenoidectomy or adenotonsillectomy on occlusal features in mouth-breathing preschoolers.
abstract: OBJECTIVE
  The purpose of this study was to evaluate mouth-breathing and nasal-breathing children prior to surgical intervention and 28 months postoperatively, comparing the occlusal features obtained pre- and postoperatively through orthodontic study casts.
  
  
  METHODS
  The  mouth-breathing (MB) group consists of 33 MB children who underwent surgery and presented a nasal-breathing (NB) pattern after surgery. The control group comprised 22 NB children. The orthodontic examinations were accomplished prior to surgery (T1) and an average of 28 months postoperatively  (T2).
  
  
  RESULTS
  At T1, the MB and NB children presented no statistically significant difference in any analyzed occlusal features and measurements. At T2, the MB presented larger overjet comparing to NB children (P<.05). MB and NB groups presented statistically similar results (P>.05)  concerning intercanine and intermolar distances, second primary molar terminal plane and canine relationship, overbite, crossbite, and open bite. From T1 to T2, the MB and NB groups showed a statistically significant difference in the molar terminal plane.
  
  
  CONCLUSIONS
  Neither the breathing  pattern nor the surgery had any effect on occlusal features in 3- to 6- year-olds.
authors.affiliation: University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Sara E M
authors.initials: SE
authors.lastname: Mattar
authors.forename: Miriam A N
authors.initials: MA
authors.lastname: Matsumoto
authors.forename: Fabiana C P
authors.initials: FC
authors.lastname: Valera
authors.forename: Wilma T
authors.initials: WT
authors.lastname: Anselmo-Lima
authors.forename: Gisele
authors.initials: G
authors.lastname: Faria
mesh_terms: D000233:Adenoidectomy; D002675:Child, Preschool; D006801:Humans; D009058:Mouth Breathing; D015508:Nasal Obstruction