Estudo cefalométrico comparativo dos espaços naso e bucofaríngeo nas más oclusões Classe I e Classe II, Divisão 1, sem tratamento ortodôntico, com diferentes padrões de crescimento

Comparative cephalometric study of the airways between different ethnic groups with normal occlusion

OBJECTIVE

This study aimed to compare the nasopharynx and oropharynx airway dimensions of Caucasians, Blacks, Japanese, Japanese Brazilians, and Black Caucasians.

METHODS

A sample of 216 lateral radiographs of untreated young Brazilian subjects (mean age of 12.94 years; SD 0.88) were divided into five groups: Black Caucasian, Black, Caucasian, Japanese, and Japanese Brazilian. Lateral radiographs were used to measure the oropharynx (from the midpoint on the soft palate to the closest point on the anterior pharyngeal wall) and the nasopharynx (from the intersection of the posterior border of the tongue and the inferior border of the mandible to the closest point on the posterior pharyngeal wall). Analyses of variance (ANOVA) and Tukey's test were performed (p< 0.05).

RESULTS

The linear dimension of the oropharynx was similar among the different ethnic groups. Caucasian individuals presented a significantly greater linear dimension of the nasopharynx than Black Caucasian and Black individuals.

CONCLUSIONS

All the groups had similar buccopharyngeal values. However, Caucasian individuals had significantly higher values when compared to Black Caucasians and Black individuals.

[Comparison of pharyngeal airway space on lateral head radiographs of skeletal class I and II individuals]

Objective

To compare the space of the pharyngeal airway (nasopharynx and oropharynx) through lateral X-ray analysis in skeletal class II individuals with a control group composed of skeletal class I individuals.

Materials and methods

This study was of the observational, descriptive, transversal, and prospective type. The sample was made up by 60 lateral head radiographs distributed between 30 class I (ANB 2°±2° and class I malocclusion) and 30 skeletal class II radiographs (ANB>5° and malocclusion class II-1). Measurements of the airway space in the oropharynx and nasopharynx were taken in mm through the McNamara method on lateral head radiographs.

Results

The average space found in the oropharynx in class I was 11.71mm ± 3.18mm. In the class II group, it was 10.73mm ± 2.36mm. No significant differences were found (p=0.18). The average space found in the nasopharynx in the class I group was 18.45mm ± 4.11mm. In the class II group, it was 19.10mm ± 3.89mm. There were no significant differences found (p=0.53).

Conclusion

The airway space in mm. of the nasopharynx presents similar values in millimeters in subjects with Class I and Class II skeletal malocclusion. There is no difference in the airway spaces of the oropharynx in subjects with Class I and Class II Malocclusions.

Assessment of upper airways measurements in patients with mandibular skeletal Class II malocclusion

Objective:

Mandibular Class II malocclusions seem to interfere in upper airways measurements. The aim of this study was to assess the upper airways measurements of patients with skeletal Class II malocclusion in order to investigate the association between these measurements and the position and length of the mandible as well as mandibular growth trend, comparing the Class II group with a Class I one.

Methods:

A total of 80 lateral cephalograms from 80 individuals aged between 10 and 17 years old were assessed. Forty radiographs of Class I malocclusion individuals were matched by age with forty radiographs of individuals with mandibular Class II malocclusion. McNamara Jr., Ricketts, Downs and Jarabak's measurements were used for cephalometric evaluation. Data were submitted to descriptive and inferential statistical analysis by means of SPSS 20.0 statistical package. Student's t-test, Pearson correlation and intraclass correlation coefficient were used. A 95% confidence interval and 5% significance level were adopted to interpret the results.

Results:

There were differences between groups. Oropharynx and nasopharynx sizes as well as mandibular position and length were found to be reduced in Class II individuals. There was a statistically significant positive correlation between the size of the oropharynx and Xi-Pm, Co-Gn and SNB measurements. In addition, the size of the nasopharynx was found to be correlated with Xi-Pm, Co-Gn, facial depth, SNB, facial axis and FMA.

Conclusion:

Individuals with mandibular Class II malocclusion were shown to have upper airways measurements diminished. There was a correlation between mandibular length and position and the size of oropharynx and nasopharynx.

Avaliação da influência do tipo facial nos tamanhos dos espaços aéreos nasofaríngeo e bucofaríngeo

INTRODUÇÃO: a diminuição no tamanho do espaço aéreo nasofaríngeo, causada pela hipertrofia da tonsila faríngea, tem sido associada a alterações no padrão normal de crescimento craniofacial e a efeitos deletérios na oclusão. OBJETIVOS: avaliar variações nos tamanhos dos espaços aéreos nasofaríngeo e bucofaríngeo de acordo com o padrão de crescimento craniofacial, a correlação entre os tamanhos dos espaços e o índice VERT, além de verificar um possível dimorfismo sexual. MÉTODOS: foi utilizado um total de 90 telerradiografias laterais de pacientes, divididos em três grupos: meso, braqui e dolicofacial, determinados por meio do índice VERT de Ricketts. Os pacientes da amostra, com idades entre 9 e 16 anos, apresentavam padrão respiratório nasal, sem qualquer tipo de obstrução. RESULTADOS: não foi verificada variação estatisticamente significante nos tamanhos dos espaços aéreos nasofaríngeo e bucofaríngeo, quando comparados os três tipos faciais. Também não foi encontrada correlação entre os tamanhos dos espaços aéreos e os valores do índice VERT de Ricketts dos pacientes e não houve dimorfismo sexual. CONCLUSÕES: pode-se descartar a influência do tipo facial nos tamanhos dos espaços aéreos nasofaríngeo e bucofaríngeo.

Growth of the nasopharynx and adenoidal development in Brazilian subjects

The purpose of this research was to study the growth of the nasopharynx and adenoid development. Lateral cephalometric radiographs obtained from 320 white Brazilian subjects between 4 and 16 years of age were used. All the participants were nose breathers and none of them had previously undergone adenoidectomy. Tracings were made from the radiographs and cephalometric measurements were performed. The results showed that adenoid sagital thickness is larger in the age group 4 - 5 years and decreases progressively. There is a slight increase in the age group 10 - 11 years, but afterwards the decrease continues. However, the nasopharyngeal free airway space does not decrease in the age group 10 - 11 years, despite the increasing thickness of the adenoid. This is attributable to the downward displacement of the hard palate, resulting in an increase of the free airway space due to growth. Although the nasopharynx follows a growth pattern similar to that of the rest of the body, adenoid tissue does not. Adenoidal development seems to differ from that of other lymphatic tissues, showing a peculiar pattern that can be revealed when hypertrophy due to infections and allergies is eliminated.