Cambios En La Via Aerea Superior Posterior A Expansion Rapida Del Maxilar En Ninos De 12 Anos

Rapid maxillary expansion is often considered the treatment of choice for the correction of maxillary constriction. Several studies highlight the effect of rapid maxillary expansion in increasing nasal length and volume. The aim of this study is quantifying the volumetric changes of the upper airway, the maximum restricted area of the upper airway and the nostrils area, after the intervention of a rapid maxillary expansion using bimaxillary CBCT. A retrospective study was carried out, in which 14 patients of 12 year old with a diagnosis of unilateral or bilateral crossbite and skeletal maxillary constriction were selected. The treatment was carried out with a Mcnamara-type rapid expansion device and 8 mm of disjunction was planned. An initial bimaxillary CBCT was requested and another 15 days after treatment. Measurements were made at the maxillary level, upper airway and the maximum restricted area and the cross section of the nostril area, using 3D measuring softwares. It was obtained that, for every 1 mm of planned disjunction, 0.65 mm of maxillary disjunction is achieved, an upper airway gain of 0.7 cm3, the maximum restricted area gain of the upper airway of 9 mm2 and a gain in the nostrils area of 7.4 mm2 on average. In conclusion rapid maxillary expansion generates a significant increase in the volume of the upper airway and its narrower area.

Disyunción maxilar rápida asistida con microtornillos en pacientes en crecimiento con deficiencia maxilar transversal / Miniscrew assisted rapid maxillary expansion in growing patients with transverse maxillary deficiency

RESUMEN: Introducción: La disyunción maxilar rápida tradicional (RME) ha sido el tratamiento de elección para corregir la maloclusión secundaria a la deficiencia maxilar transversal. Debido a las complicaciones que pueden presentar los pacientes, se han desarrollado técnicas de disyunción maxilar asistida por microtornillos (MARPE). Sin embargo, aún no hay consenso respecto a los reales beneficios de la disyunción maxilar rápida asistida por microtornillos por sobre la disyunción tradicional en pacientes jóvenes y en crecimiento. Métodos: Realizamos una búsqueda en Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, la cual es mantenida mediante el cribado de múltiples fuentes de información, incluyendo MEDLINE, EMBASE, Cochrane, entre otras. Extrajimos los datos desde las revisiones identificadas, analizamos los datos de los estudios primarios, realizamos un metanálisis y preparamos una tabla de resumen de los resultados utilizando el método GRADE. Resultados y conclusiones: Identificamos siete revisiones sistemáticas que en conjunto incluyeron seis estudios primarios, de los cuales todos corresponden a ensayos aleatorizados. Concluimos que: la disyunción maxilar rápida asistida por microtornillos (MARPE) probablemente disminuye la pérdida de hueso alveolar bucal y la resistencia de la vía aérea nasal en comparación a la disyunción maxilar rápida tradicional (RME) (certeza evidencia moderada). MARPE podría disminuir la inclinación dentaria y resultar en poca o nula diferencia en la percepción de dolor en comparación con RME (certeza de la evidencia baja). No es posible establecer con claridad si MARPE aumenta la expansión maxilar en comparación con RME, debido a que la certeza de la evidencia ha sido evaluada como muy baja.

ABSTRACT: Introduction: Traditional rapid maxillary expansion (RME) has been the gold-standard treatment to correct malocclusion secondary to transverse maxillary deficiency. Due to related complications, mini screw assisted maxillary expansion (MARPE) techniques have been developed. However, there is no consensus regarding the benefits of mini screw assisted maxillary expansion over traditional expansion in young and growing patients. Methods: We searched in Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. Results and conclusions: We identified seven systematic reviews including six studies overall, all of which were randomized trials. We concluded that mini screw maxillary expansion (MARPE) probably reduces buccal alveolar bone and nasal airway resistance compared to traditional rapid maxillary expansion (RME). MARPE may reduce dental inclination and result in little or no difference in pain perception compared to RME. We are uncertain whether MARPE improves maxillary expansion compared to RME, as the certainty of the evidence has been assessed as very low.

Evaluating the effect of midpalatal corticotomy-assisted rapid maxillary expansion on the upper airway in young adults using computational fluid dynamics / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Midpalatal corticotomy-assisted rapid maxillary expansion (MCRME) is a minimally invasive treatment of maxillary transverse deficiency (MTD) in young adults. However, the effect of MCRME on respiratory function still needs to be determined. In this study, we evaluated the changes in maxillary morphology and the upper airway following MCRME using computational fluid dynamics (CFD). Twenty patients with MTD (8 males, 12 females; mean age 20.55 years) had cone-beam computed tomography (CBCT) images taken before and after MCRME. The CBCT data were used to construct a three-dimensional (3D) upper airway model. The upper airway flow characteristics were simulated using CFD, and measurements were made based on the CBCT images and CFD. The results showed that the widths of the palatal bone and nasal cavity, and the intermolar width were increased significantly after MCRME. The volume of the nasal cavity and nasopharynx increased significantly, while there were no obvious changes in the volumes of the oropharynx and hypopharynx. CFD simulation of the upper airway showed that the pressure drop and maximum velocity of the upper airway decreased significantly after treatment. Our results suggest that in these young adults with MTD, increasing the maxillary width, upper airway volume, and quantity of airflow by MCRME substantially improved upper airway ventilation.

Cone-Beam CT evaluation of upper airway following rapid maxillary expansion and maxillary protraction for the treatment of skeletal class Ⅲ malocclusion / 实用口腔医学杂志

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.

Rapid maxillary expansion in the treatment of obstructive sleep apnea syndrome:A case report / 实用口腔医学杂志

1 case of OSAS was treated by valuating rapid maxillary expansion,sleep monitoring indicated that the device reduced nasal re-sistance and improved respiratory function of the patient.

Clinical study of surgically assisted rapid maxillary expansion

Orthopedic rapid maxillary expansion(RME) has been a common treatment modality used to widen narrow maxillae in young children. However, since more skeletally matured adolescents or adults has closed midpalatal suture, the result of RME was undesirable because of dental tipping with little or no basal skeletal movement and resulted to many other complications. After such treatment, complications often occurred such as alveolar bending, compression of periodontal ligament, extrusion, buccal tipping, and severe relapse. Thus, surgically assisted rapid maxillary expansion(SA-RME) is required, especially for patients over 14 years old, to skeletally release maxillary expansion. We used two methods of maxillary expansion surgery. Surgically assisted rapid maxillary expansion(SA-RME) and surgically assisted posterior segmental expansion(SA-PSE) were used for narrow maxilla. The study was divided into two groups(SA-RME group and SA-PSE group). SA-RME group was consisted of 2 males and 4 females, and the ages of materials ranged from 15 years to 25 years with a mean of 20.2 years. SA-PSE group was consisted of 1 male and 5 females, and the ages ranged from 13 years to 23 years with a mean of 18.7 years. Dental study models were fabricated before starting the expansion and immediately after the expansion was completed. It was fabricated again 1 month later, 3 months later when the expansion device was removed, and 6 months later after the expansion was completed. A repeated measures analysis of variance(ANOVA) test was applied to assess changes between each groups over time. The amount of expansion and the amount of tipping movement each in both groups were compared by using paired t-test and it was also compared between each subjects within the group by using independent t-test. Both SA-RME and SA-PSE group showed stable results, but SA-PSE group showed statical significance in tipping movement of second premolar. We compared 6 patients who recieved SA-RME with 6 patients who received SA-PSE, and appraised the clinical usefulness.