ABSTRACT
Objective:To analyze the 3D changes of pharyngeal airway in patients with skeletal Class Ⅲ malocclusion after rapid maxillary expansion(RME)and maxillary protraction.Methods:53 patients underwent orthodontic treatment with Hyrax palatal ex-panders and maxillary protraction.Cone-Beam computed tomography(CBCT)scan was taken before treatment(T0),after 1 6 d RME (T1 )and after about 5 month maxillary protraction(T2).Data were reconstructed into 3D model,sagittal and transversal measure-ments,cross sectional areas,volumes of the pharyngeal airway were computed.Results:After RME,the transversal measurements, cross sectional areas,volumes of nasal passage were increased(P <0.05).After maxillary protraction,the 4 nasopharyngeal measure-ments were increased(P <0.05).Conclusion:RME and maxillary protraction may increase pharyngonasal airway.
ABSTRACT
<p><b>OBJECTIVES</b>To evaluate the naso-maxillary complex width and pharyngeal airway volume changes after rapid maxillary expansion (RME).</p><p><b>METHODS</b>Thirty-five patients were selected (18 males, 17 females, mean age, 12.1 ± 1.1 years). All patients underwent orthodontic treatment with Hyrax palatal expanders. Cone-beam CT (CBCT) scan was taken before treatment (T0), 16 days (T1) and three months (T3) after RME. Naso-maxillary complex width and pharyngeal airway volume were measured.</p><p><b>RESULTS</b>After treatment the width of piriform aperture and maxillary width were significantly increased compared with that before treatment (P < 0.05). Three months after RME, no statistical difference was found in maxillary width compared with that before treatment. The nasopharyngeal volume significantly increased by 29.9% compared with that before treatment (P < 0.05), and the volume remained relatively stable after three months.</p><p><b>CONCLUSIONS</b>RME resulted in a significant increase in the naso-maxillary complex width and nasopharyngeal volume.</p>
Subject(s)
Female , Humans , Male , Cone-Beam Computed Tomography , Imaging, Three-Dimensional , Maxilla , Diagnostic Imaging , Nose , Diagnostic Imaging , Palatal Expansion Technique , Palate , Diagnostic Imaging , Pharynx , Diagnostic ImagingABSTRACT
<p><b>OBJECTIVE</b>To evaluate the short-term and long-term effects of pharyngeal airway in mandibular prognathism patients after the combined orthodontic and orthognathic treatment.</p><p><b>METHODS</b>The sample included 28 skeletal Class III patients (13 males, 15 females) who had undergone mandibular setback surgery and orthodontic treatment. Cone-beam CT was taken one week before treatment (T0), 6 months (T1) and 3 years after surgery (T2). Raw data were reconstructed into three-dimensional model. Sagittal and transversal measurements, cross sectional areas, partial and total volumes were computed.</p><p><b>RESULTS</b>Six months after surgery, oropharyngeal volume [(9 021 ± 4 263) mm³], hypopharyngeal volume [(9 236 ± 5 963) mm³] and total volume [(28 619 ± 9 854) mm³] decreased significantly (P < 0.05). Three years after surgery, only sagittal diameters [(15.9 ± 3.5) mm] and cross sectional areas [(996 ± 398) mm²] in the first cervical vertebra plane came back to the original levels (P > 0.05).</p><p><b>CONCLUSIONS</b>The pharyngeal airway space decreased after orthodontic-orthognathic therapy in the short term and it increased in some areas in the long term.</p>