title: N-butanol olfactory threshold and nasal patency before and after palatal expansion in children. A preliminary study.
abstract: OBJECTIVE
  Olfaction is based on the function of the nasal olfactory receptors. Children can well detect and respond to odors in order to have information about food and environment. Rapid maxillary expansion seems to improve dental class and increase nasal patency correcting oral respiration in children. Nevertheless, there are no studies demonstrating that expansion in pediatric patients could influence olfactory sensitivity. The aim of this study was to evaluate olfactory threshold and nasal patency in children aged from 6 to 12 years before and after rapid maxillary expansion.
  
  
  METHODS
  N-butanol olfactory thresholds, anterior active rhinomanometry, and peak nasal inspiratory flow were measured in 12 children (6-12 years) before (T0), 20 days (T1), and 6 months after rapid maxillary expansion application (T2).
  
  
  RESULTS
  A significant lower olfactory threshold was found comparing T2 and T0 N-butanol olfactory threshold values (p=0.038). Peak nasal inspiratory flow showed a significant improvement both at T1 and T2, with respect to T0 values (p=0.043 and p=0.0001, respectively). T2 nasal resistances showed a trend towards a significant reduction when compared with T1 values (p=0.15).
  
  
  CONCLUSIONS
  This pilot study suggested that rapid maxillary expansion may lead to improved N-butanol olfactory thresholds, at least 6 months after palatal expansion. Furthermore, rapid maxillary expansion seems to improve peak nasal inspiratory flow values, and finally although with lower sensitivity, reduce nasal resistances as measured by rhinomanometry.
authors: Department of Neurosciences, Otolaryngology Section, University of Padova, Padova, Italy. Electronic address: giancarlo.ottaviano@unipd.it.
authors: G
authors: G
authors: Ottaviano
authors: Department of Neurosciences, Otolaryngology Section, University of Padova, Padova, Italy.
authors: G
authors: G
authors: Frasson
authors: Department of Surgery, Dentistry and Maxillofacial Unit, University of Verona, Verona, Italy.
authors: V
authors: V
authors: Favero
authors: Department of Neurosciences, Odontostomatology Institute, University of Padova, Padova, Italy.
authors: M
authors: M
authors: Boato
authors: Department of Neurosciences, Odontostomatology Institute, University of Padova, Padova, Italy.
authors: E
authors: E
authors: Schembri
authors: Department of Neurosciences, Otolaryngology Section, University of Padova, Padova, Italy.
authors: R
authors: R
authors: Marchese-Ragona
authors: Department of Molecular Medicine, University of Padova, Padova, Italy.
authors: C
authors: C
authors: Mucignat-Caretta
authors: Department of Neurosciences, Odontostomatology Institute, University of Padova, Padova, Italy.
authors: E
authors: E
authors: Stellini
authors: Department of Neurosciences, Otolaryngology Section, University of Padova, Padova, Italy.
authors: A
authors: A
authors: Staffieri
authors: Department of Neurosciences, Odontostomatology Institute, University of Padova, Padova, Italy.
authors: L
authors: L
authors: Favero
mesh_terms: D020001:1-Butanol; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D010155:Palatal Expansion Technique; D010865:Pilot Projects; D011184:Postoperative Period; D057234:Preoperative Period; D025363:Rhinomanometry; D012903:Smell
chemical_list: D020001:1-Butanol
keywords: AAR; Children.; N-butanol olfactory threshold; PNIF; Rapid maxillary expansion