Effects of rapid maxillary expansion on middle ear function: one-year follow-up.
OBJECTIVE
To evaluate the effects of rapid maxillary expansion (RME) on middle ear function before, after, 3 months and one year from expansion procedure.


METHODS
Eighteen patients with mean age of 8.1 years (±3.7) and posterior cross-bite were followed from pre expansion to one year after RME, regarding their hearing quality and middle ear function. Nine of them presented middle ear dysfunction (MED) and nine presented normal function (NF) before rapid maxillary expansion. Audiometric and tympanometric exams were taken before rapid maxillary expansion, after RME (15 days), 3 months and one year after rapid maxillary expansion.


RESULTS
Among those in the MED group, no patient had acoustic reflex (AR) before rapid maxillary expansion; 67% presented type C tympanometric curve, 22% had type A and 11% had As type tympanometric curve. One year after rapid maxillary expansion, all patients presented AR and showed type A tympanometric curves. In NF group, all patients showed AR and type A tympanometric curves in all records. In both groups no audiograms presented significant variations along study.


CONCLUSIONS
Rapid maxillary expansion has no deleterious effect in hearing quality and seems to improve middle ear function in children with posterior cross-bite in a one-year perspective.
Dentistry Department, Universidade Estadual de Maringa, Parana, Brazil. kellymicheletti@hotmail.com
Kelly Regina
KR
Micheletti
Jaqueline Aparecida
JA
de Mello
Silvia Regina
SR
de Almeida Barreto Ramos
Paula Cabrini
PC
Scheibel
Gilberto Giampá
GG
Scheibel
Adilson Luiz
AL
Ramos
D000158:Acoustic Impedance Tests; D001299:Audiometry; D002648:Child; D004432:Ear, Middle / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D006309:Hearing / Q000502:physiology*; D006801:Humans; D008297:Male; D008310:Malocclusion / Q000628:therapy*; D010155:Palatal Expansion Technique