Effects of rapid maxillary expansion on upper airway parameters in OSA children with maxillary restriction: A CBCT study.

BACKGROUND: Rapid maxillary expansion (RME) has been proposed as an effective treatment for pediatric obstructive sleep apnea (OSA) and maxillary restriction in children. This study aimed to evaluate the effect of RME appliances on the nasomaxillary complex dimensions in children with OSA and maxillary constriction. METHODS: This prospective longitudinal study included 34 children aged 8-12 years with maxillary restriction and OSA confirmed by polysomnography who had completed RME therapy. The nasomaxillary complex is segmented into the nasal cavity, maxillary sinuses, and nasopharynx. The effect of RME on nasomaxillary complex dimensions was assessed pre and posttreatment using cone-beam computed tomography, analysis, while a second standard overnight polysomnography (PSG) was performed to assess changes in respiratory parameters. RESULTS: Significant improvements were observed, including inferior maxillary dislocation (S-S1 distance and N-ANS), increased anterior and posterior facial height, and a 5.43 events/h reduction in Apnea-Hypopnea Index (p < .001). The nasal cavity volume increased by 2439 (±584) mm3 (p < .001), nasopharynx size increased by 883 (±479) mm3 (p = .008), mid cross-sectional area increased by 31.74 (±14.50) mm2 (p < .001), and the distance between the right and left maxillary sinuses increased by 8.37 (±3.67) mm (p < .001) all exhibited positive changes, with some insignificant variations in volume change (p = .254). CONCLUSION: RME treatment was found to be effective in improving nasal cavity and nasopharyngeal dimensions, leading to improved respiratory parameters in children with OSA and maxillary constriction. While these results are promising, considerations about the potential long-term benefits of RME on future growth are important. The study provides valuable insights into the efficacy of RME as a treatment option for this pediatric population.

Internal structural analysis of the nasomaxillary complex in patients with skeletal class III asymmetry: A study on asymmetry patterns.

OBJECTIVES: To investigate the internal structure of the nasomaxillary complex, including the maxillary sinus, nasal cavity and nasal septum according to the facial asymmetry pattern and to evaluate its correlation with external maxillomandibular asymmetry in Class III patients based on cone-beam computerized tomography (CBCT) images. MATERIALS AND METHODS: Facial asymmetry was analysed in a total of 100 Class III patients aged 16 years or older using CBCT scans. Patients were categorized into subgroups based on asymmetry pattern. Measurements of the nasomaxillary complex were obtained from the CBCT scans, including the volume and width of the maxillary sinuses and nasal cavities on deviated and non-deviated sides, as well as the displacement of the nasal septum. Statistical analysis was performed to compare the internal nasomaxillary variables within and between groups, and regression analysis was conducted to evaluate the correlation between facial asymmetry and the internal nasomaxillary variables. RESULTS: Group comparisons showed that there were no significant differences in the volume of the maxillary sinus and nasal cavity. However, the direction and extent of nasal septum deviation, as well as the width of the nasal cavity, varied depending on the maxillary asymmetry pattern. Regression analysis indicated a correlation between nasal septum deviation and the difference in maxillary height, while the difference in nasal cavity width was correlated with the difference in maxillary width. CONCLUSION: A comprehensive evaluation of the internal nasal anatomy is vital for understanding the intricate relationship between nasal structure and maxillary growth.

Estudo da anatomia do septo nasal e sua relação com a morfologia do complexo nasomaxilar / Study of the anatomy of the nasal septum and its relationship with the morphology of the nasomaxillary complex

O presente estudo teve como objetivo investigar a influência do desvio do septo nasal (DSN) na morfologia do complexo nasomaxilar quanto a confiabilidade e precisão na marcação de pontos craniofaciais bidimensionais (2D) e tridimensionais (3D) em imagens de tomografia computadorizada de feixe cônico (TCFC), verificação de assimetrias do complexo nasomaxilar em indivíduos com diferentes níveis de DSN em estágios de maturação esquelética distintos, e analisar a associação entre o grau de severidade do DSN e o grau de assimetria do complexo nasomaxilar. Este foi um estudo observacional retrospectivo que utilizou um total de 60 TCFC alocadas em 4 grupos (n = 15) de acordo com o grau de desvio septal e maturação esquelética (DSN <10°, desvio de septo nasal leve, e DSN >10°, desvio de septo nasal moderado a severo, ambos antes e depois do surto de crescimento). A etapa de validação do estudo compreendeu a utilização de 30 TCFC e demarcação de 25 pontos craniofaciais, a fim de avaliar a confiabilidade e precisão desses pontos nas regiões nasal, palatina e facial lateral. Dois métodos foram utilizados: 2D, em cortes multiplanares de TCFC no programa CS 3D Imaging; e 3D, com a segmentação 3D do crânio com visualização simultânea dos cortes multiplanares no programa ITK Snap. Os dados das coordenadas foram analisados por meio do Índice de Correlação Intraclasse (ICC), média das diferenças entre os tempos das medições, fórmula de Dahlberg e gráficos de Bland-Altman. A análise da relação entre a anatomia do septo nasal e morfologia do complexo nasomaxilar, compreendeu a utilização de 60 TCFC e a demarcação de 23 pontos bidimensionais e, avaliados quanto a presença de assimetria flutuante, por meio da análise de Procrustes ANOVA, comparação intergrupos com o teste de Mann- Whitney, além do teste de correlação de Spearman e regressão multivariada (a=0,05). Os resultados obtidos nas avaliações da reprodutibilidade dos pontos craniofaciais nos mostraram que o ICC variou de 0,95 a 1,0 no método 2D e foi maior ou igual a 0,99 no método 3D, indicando que ambos os métodos tiveram alta confiabilidade. A fórmula de Dahlberg, juntamente com Bland-Altman indicaram menor precisão nos pontos zigomáticomaxilar e orbitário no método 3D, e sutura zigomáticotemporal no método 2D. Os pontos ímpares (a maioria no plano sagital mediano) e os pontos frontozigomático temporal e frontozigomático orbital tiveram os melhores resultados de precisão. Com relação a influência do DSN e assimetrias no complexo nasomaxilar, nossos resultados principais mostraram que não foram observadas diferenças estatisticamente significativas entre as distâncias de Procrustes e Mahalanobis (assimetria flutuante) do complexo nasomaxilar entre os grupos avaliados (P>0.05). Entretanto, com os resultados da regressão multivariada, relacionado aos aspectos mais específicos de assimetria (componente assimétrico), houve uma correlação positiva entre o ângulo DSN e componente assimétrico das regiões palatinas (P=0.035 e P=0.047, média e posterior, respectivamente), e também com a forma do SN e componente assimétrico da região palatina anterior (P=0.039). Sendo assim, concluímos que, ambos os métodos 2D e 3D de marcação de pontos craniofaciais no complexo nasomaxilar e facial lateral apresentaram alta confiabilidade, entretanto, o método 2D apresentou maiores valores de precisão na maioria dos pontos avaliados. Além disso, todos os pontos avaliados neste estudo foram considerados aceitáveis para fins clínicos. Com relação a análise da anatomia do septo nasal e morfologia do complexo nasomaxilar, todos os grupos avaliados apresentaram níveis significativos de assimetria flutuante. Entretanto, não foram observadas diferenças significativas na assimetria flutuante do complexo nasomaxilar nos grupos com DSN leve em relação aos grupos com DSN moderado a severo, em ambos os estágios de maturação esquelética. Por fim, foi observada correlação positiva entre o ângulo DSN e o componente de assimetria nas regiões palatinas média e posterior e entre a forma do septo nasal e a região palatina anterior. Não foram observadas correlações significativas com as regiões nasal e lateral do complexo nasomaxilar. (AU)

The present study aimed to investigate the influence of nasal septum deviation (NSD) on the morphology of the nasomaxillary complex regarding reliability and accuracy in two-dimensional (2D) and three-dimensional (3D) craniofacial landmarks in cone beam computed tomography images (CBCT), verification of asymmetries of the nasomaxillary complex in individuals with different levels of NSD at different stages of skeletal maturation, and to analyze the association between the degree of severity of the NSD and the degree of asymmetry of the nasomaxillary complex. This was a retrospective, crosssectional observational study that used a total of 60 CBCT. For the validation study, 30 CTBC were used and 25 craniofacial landmarks were marked, in order to compare the reliability and precision of these landmarks in the nasal, palatal and lateral facial regions. Two methods were used: 2D, in CBCT multiplanar sections using CS 3D Imaging Software; and 3D, from the 3D segmentation of the skull in the software ITK Snap associated with multiplanar sections. Coordinates data were analyzed using the Intraclass Correlation Coefficient (ICC), Dalhberg's formula, Bland-Altman plots and mean differences between measurement trials. To study the relationship between nasal septum and nasomaxillary complex, the 60 CBCT were divided into 4 groups (n = 15) according to the degree of septal deviation and skeletal maturation (NSD <10°, mild nasal septum deviation, e NSD >10°, moderate to severe nasal septum deviation, both before and after the growth spurt). 23 two-dimensional landmarks were marked and, to assess asymmetries, we used Procrustes ANOVA, intergroups comparisons with the Mann-Whitney test, in addition to the Spearman's correlation test and multivariate regression. The results obtained in the evaluations of the reliability and precision of craniofacial landmarks showed that the ICC ranged from 0.95 to 1.0 in the 2D method and was greater than or equal to 0.99 in the 3D method, indicating that both methods had high reliability. Dahlberg's formula, together with Bland-Altman, indicated lower precision in the landmarks zygomaxillare and orbitale in the 3D method, and zygomaticotemporal suture in the 2D method. The unpaired landmarks (mainly located at the midsagittal plane) and the landmarks frontomalar temporale and frontomalar orbitale had the best results of precision. Regarding the influence of NSD and asymmetries in the nasomaxillary complex, our main results showed that no statistically significant differences were observed between the Procrustes and Mahalanobis distances (fluctuating asymmetry) of the nasomaxilar complex between the groups (P>0.05). However, with the results of the multivariate regression, related to the more specific aspects of asymmetry (asymmetry component), there was a positive correlation between the NSD angle and palatal regions (P=0.035 and P=0.047, middle and posterior, respectively), and also with the shape of the NS and the anterior palatal region (P=0.039). Therefore, we conclude that both the 2D and 3D methods of positioning craniofacial landmarks in the nasomaxillary complex and the lateral facial region showed high reliability, however, the 2D method showed higher precision values in most of the landmarks evaluated. Furthermore, all landmarks evaluated in this study are are reasonably considered acceptable for clinical purposes. Regarding the study of the nasal septum and nasomaxillary complex, all groups evaluated presented significant levels of fluctuating asymmetry. However, no significant differences were observed in the fluctuating asymmetry of the nasomaxillary complex in the groups with mild NSD compared to the groups with moderate to severe NSD, in both stages of skeletal maturation. Finally, a positive correlation was observed between the NSD angle and the asymmetry component in the middle and posterior palatine regions and between the shape of the nasal septum and the anterior palatine region asymmetry component. There were no significant correlations with the nasal and lateral regions of the nasomaxillary complex. (AU)

Molar inclination and surrounding alveolar bone change relative to the design of bone-borne maxillary expanders: A CBCT study.

OBJECTIVE: To evaluate the molar inclination and skeletal and alveolar bone changes when comparing tooth bone-borne (MSE) and tissue bone-borne type maxillary expanders (C-expander) using cone-beam computed tomography (CBCT) in late adolescence. MATERIALS AND METHODS: A sample of 48 late-adolescent patients were divided into two groups according to the type of expander: MSE group (n = 24, age = 19.2 ± 5.9 years) and C-expander group (n = 24, age = 18.1 ± 4.5 years). CBCT scans were taken before treatment and 3 months after expansion. Transverse skeletal and dental expansion, alveolar inclination, tooth axis, buccal alveolar bone height, thickness, dehiscence, and fenestration were evaluated on the maxillary first molar. Paired t-test, independent t-test, Pearson's chi-square test, and Spearman correlation analysis were performed. RESULTS: The MSE group produced greater dental expansion (P < .05), whereas skeletal expansion was similar in both groups (P = .859). The C expander group had more alveolar bone inclination change (P < .01), and the MSE group had more buccal tipping of the anchorage teeth (P < .01 or .001). Buccal alveolar bone height loss and thickness changes were greater in the MSE group (P < .01 or <.001). Formation of dehiscences was more frequent in the MSE group (P < .001), whereas for fenestrations, there were no significant differences between the two groups. Buccal bone height loss in the MSE group had a negative correlation with initial buccal bone thickness. CONCLUSIONS: The incorporation of teeth into bone-borne expanders resulted in an increase in the severity of side effects. For patients in late adolescence, tissue bone-borne expanders offer comparable skeletal effects to tooth bone-borne expanders, with fewer dentoalveolar side effects.

Impairment of nasal airway under intermittent hypoxia during growth period in rats.

OBJECTIVE: To clarify the influences of intermittent hypoxia (IH) on the growth and development of the midfacial area, including the nasal cavity, in growing rats. DESIGN: Seven-week-old male Sprague-Dawley rats were divided into two groups: the experimental group (n=5), which was exposed to IH for 8h during light periods at a rate of 20 cycles/h (nadir, 4% O2 to peak, 21% O2 with 0% CO2), and the control group (n=5), which was exposed to room air. After 3 weeks, the maxillofacial structures in both groups were evaluated with respect to the height, width, length, surface area, cross-sectional area, and volume of the nasal cavity using soft X-ray and micro-CT. RESULTS: The experimental group showed a significantly smaller cross-sectional area and volume than did the control group. The surface area exhibited no significant differences between the two groups, although it tended to be smaller in the experimental group than in the control group. The nasal volume divided by the length of the tibia (for comparison with whole-body growth) was significantly smaller in the experimental group than in the control group. CONCLUSIONS: These data suggest that IH exposure suppresses growth and development of the nasal cavity and may result in nasal breathing disturbance.

A study on the relationship between maxillary protraction treatment and changes of nasomaxillary complex facial soft tissue of children with skeletal Class m malocclusion / 国际儿科学杂志

Objective To investigate nasomaxlllary complex facial soft tissue changes after the treatment with maxillary protraction appliance with skeletal Class Ⅲ malocclusion with a retruded maxilla.Methods Thirty growing subjects with skeletal Class Ⅲ malocclusions with maxillary retrognathism were selected and treated by facial mask(male 15,female 15,with an average age of 10.5).They were given a maxillary protraction treatment with face mask for 6-8 months.Cephalometric measurements about nasomaxillary complex soft tissue changes were analyzed to draw the statistic conclusion.Results After maxillary protraction treatment,PraY,nasofrontal angle,As-Y,UL-Y,UL-E,S-Ns-Sn increased (P ＜ 0.01) ; M-Y increased (P ＜ 0.05) ; LL-E,PosY,nasolabial angle decreased (P ＜ 0.05).There were no significant differences in the Ns-Y and columella-tip angle.Conclusion After maxillary protraction treatment,nasomaxillary complex area becomes more marked.Both the nasomaxillary complex soft tissue and lower facial profile are dramatically improved.The combining effect of these two changes results in a more harmony profile.