Effect of rapid maxillary expansion on the dimension of the nasal cavity and on nasal air resistance.
BACKGROUND
Atresia of the maxilla is a transverse skeletal dysplasia, possibly associated with respiratory problems. For its correction, rapid maxillary expansion is a feasible orthodontic process.


OBJECTIVE
To evaluate the effect of rapid maxillary expansion on the nasal cavity by acoustic rhinometry and computed rhinomanometry.


METHODS
Twenty-nine children of both sexes with oral and/or mixed breathing, ranging in age from 7 to 10 years and with mixed dentition were selected. The children had uni- or bilateral posterior crossbite involving deciduous canines and the first permanent molars and were not being submitted to any otorhinolaryngologic or orthodontic treatment. All subjects were submitted to rhinologic exams and orthodontic documentation at three different times, i.e., before expansion and immediately and 90 days after expansion.


RESULTS
There was no difference in the minimal cross-sectional area at the level of the valve and inferior nasal turbinate between the periods analyzed, but there was a statistically significant reduction in nasal resistance after expansion.


CONCLUSIONS
On the basis of the present results, we may conclude that rapid maxillary expansion may lessen the nasal resistance. Although there was no difference in nasal geometry. Thus, this procedure may improve nasal respiration, but cannot be indicated for this purpose by itself.
Department of Pathology, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil.
Carla
C
Enoki
Fabiana Cardoso Pereira
FC
Valera
Fernanda Campos Rosetti
FC
Lessa
Ana Maria
AM
Elias
Mirian Aiko N
MA
Matsumoto
Wilma Terezinha
WT
Anselmo-Lima
D000402:Airway Obstruction / Q000473:pathology / Q000503:physiopathology / Q000628:therapy*; D000403:Airway Resistance; D002508:Cephalometry; D002648:Child; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008310:Malocclusion; D008437:Maxilla / Q000002:abnormalities*; D009296:Nasal Cavity / Q000473:pathology* / Q000502:physiology; D010155:Palatal Expansion Technique; D011446:Prospective Studies; D023842:Rhinometry, Acoustic; D016896:Treatment Outcome; D014420:Turbinates / Q000473:pathology / Q000502:physiology