title: Variation of patterns of malocclusion by site of pharyngeal obstruction in children.
abstract: OBJECTIVE
  To correlate the type of dental occlusion and the type of pharyngeal lymphoid tissue obstruction in children.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  Ambulatory ear, nose, and throat clinic of Faculdade de Medicina da Universidade de São Paulo.
  
  
  METHODS
  One hundred fourteen children aged 3 to 12 years presenting with mouth breathing and snoring due to tonsil and/or adenoid enlargement.
  
  
  METHODS
  Oroscopy and nasal fiber pharyngoscopy complemented by lateral head radiography to diagnose the type of obstruction, and clinical examination to evaluate the dental occlusion.
  
  
  METHODS
  Tonsil and adenoid obstruction (classified from grades 1-4) and sagittal, transverse, and vertical evaluation of dental occlusion.
  
  
  RESULTS
  Obstructive enlargement of both tonsils and adenoids was detected in 64.9% of the sample; isolated enlargement of the adenoids, in 21.9%; isolated enlargement of the palatine tonsils, in 7.0%; and nonobstructive tonsils and adenoids, in 6.1%. All types of pharyngeal obstruction were related to a high prevalence of posterior crossbite (36.8%). Statistically significant association was found between sagittal dental occlusion and the site of lymphoid tissue obstruction (P = .02). A higher rate of class II relationship (43.2%) was detected in the group with combined adenoid and tonsil obstructive enlargement. Isolated tonsil obstruction showed a higher rate of class III relationship (37.5%).
  
  
  CONCLUSIONS
  Different sites of obstruction of the upper airway due to enlarged lymphoid tissue are associated with different types of dental malocclusion. Findings are relevant to orthodontic and surgical decision making in these mouth-breathing patients.
authors.affiliation: Department of Otorhinolaryngology, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, Higienopolis, CEP-01228-100, São Paulo, SP, Brazil. walterrnj@gmail.com
authors.forename: Walter Ribeiro
authors.initials: WR
authors.lastname: Nunes
authors.forename: Renata Cantisani
authors.initials: RC
authors.lastname: Di Francesco
mesh_terms: D000234:Adenoids / Q000473:pathology*; D000402:Airway Obstruction / Q000209:etiology*; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008310:Malocclusion / Q000150:complications*; D009058:Mouth Breathing / Q000209:etiology; D014066:Palatine Tonsil / Q000473:pathology*; D010614:Pharynx / Q000473:pathology*; D012913:Snoring / Q000209:etiology