title: Allergic rhinitis as a possible risk factor for malocclusion: a case-control study in children.
abstract: BACKGROUND
  Prolonged oral respiration is known to cause postural alterations, which can lead to dental malocclusions. Allergic rhinitis, a common cause of upper airway obstruction in children, must therefore be seen as a possible risk factor in the development of malocclusions.
  
  
  OBJECTIVE
  Aim of this study was to investigate the association between allergic rhinitis and malocclusions in primary and early-mixed dentition.
  
  
  METHODS
  A case-control study was carried out involving 275 Italian children aged 5-9. The case group and the control group were composed of 125 individuals affected by malocclusions and by 150 healthy patients, respectively. Through a questionnaire, we assessed the presence of professionally diagnosed allergic rhinitis. Data were analysed to identify associations between these variables and the presence of malocclusions.
  
  
  RESULTS
  Children with a history of allergic rhinitis had a threefold increased risk to develop one or more dento-skeletal alterations [OR = 3.16; 95% CI (1.79-5.58), P < 0.001]. Statistically significant associations were found between allergic rhinitis and the development of posterior crossbite and increased overjet. No significant association was found for anterior openbite.
  
  
  CONCLUSIONS
  Allergic rhinitis is a significant risk factor for the development of malocclusions in general and is associated with the development of posterior crossbite and increased overjet.
authors.affiliation: Department of Oral and Maxillo-Facial Sciences, Sapienza University of Rome, Roma, Italy. v.luzzi@tiscali.it
authors.forename: Valeria
authors.initials: V
authors.lastname: Luzzi
authors.forename: Gaetano
authors.initials: G
authors.lastname: Ierardo
authors.forename: Annamaria
authors.initials: A
authors.lastname: Viscogliosi
authors.forename: Miriam
authors.initials: M
authors.lastname: Fabbrizi
authors.forename: Giuliana
authors.initials: G
authors.lastname: Consoli
authors.forename: Iole
authors.initials: I
authors.lastname: Vozza
authors.forename: Annarita
authors.initials: A
authors.lastname: Vestri
authors.forename: Antonella
authors.initials: A
authors.lastname: Polimeni
mesh_terms: D001249:Asthma / Q000150:complications; D016022:Case-Control Studies; D002508:Cephalometry / Q000379:methods; D002648:Child; D002675:Child, Preschool; D003818:Dentition, Mixed; D005260:Female; D006801:Humans; D008297:Male; D008310:Malocclusion / Q000209:etiology*; D009058:Mouth Breathing / Q000150:complications; D010031:Otitis / Q000150:complications; D057887:Overbite / Q000209:etiology; D065631:Rhinitis, Allergic; D012221:Rhinitis, Allergic, Perennial / Q000150:complications*; D006255:Rhinitis, Allergic, Seasonal / Q000150:complications; D012307:Risk Factors; D012852:Sinusitis / Q000150:complications; D020181:Sleep Apnea, Obstructive / Q000150:complications; D012913:Snoring / Q000150:complications; D014069:Tonsillitis / Q000150:complications; D014094:Tooth, Deciduous