Relationship of the airway size to the mandible distance in Chinese skeletal Class I and Class II adults with normal vertical facial pattern

Comparing Pharyngeal Airway Dimensions and Hyoid Bone Position in the Subgroups of Skeletal Class III Malocclusions: A Cephalometric Study

Aim:

To examine pharyngeal airway dimensions and hyoid bone position according to the subgroups of Class III malocclusion.

Materials and Methods:

This retrospective study consisted of patients divided into three subgroups with skeletal Class III malocclusion. The study included a total of 151 individuals (61 females and 90 males). The authors divided individuals with skeletal Class III malocclusion into three subgroups: maxillary retrognathia, mandibular prognathia, and combined. The study’s cephalometric analysis used eight nasopharyngeal, seven oropharyngeal, two hypopharyngeal, nine hyoid, and four area measurements. One-way analysis of variance was used to evaluate patients. Tukey’s post-hoc tests were used for bilateral comparisons of significant parameters. The results were considered statistically significant at a P < .05 significance level.

Results:

The study found no significant differences between the groups’ pharyngeal airway and area measurements ( P > .05). When the authors evaluated hyoid bone position, a statistically significant difference was found between the three groups’ Hy-A (mm), Hy-S (mm), Hy-SN (mm), and Hy-FH (mm) measurements ( P < .05).

Conclusion:

Linear and areal pharyngeal airway dimensions are similar in subgroups of Class III malocclusions, while the hyoid bone is vertically higher in individuals with maxillary retrognathia.

Upper airways evaluation in young adults with an anterior open bite: A CBCT retrospective controlled and cross-sectional study

OBJECTIVE

To compare the dimensions of the upper airway in young adults with anterior open bite versus matched individuals with an adequate overbite (control group) using different measurement approaches (linear, area, and volume measures).

MATERIALS AND METHODS

The sample included 137 cone-beam computed tomographies (CBCTs) of young adults (74 men and 63 women) divided into two groups: 47 CBCTs of individuals (mean age 27.89) with open bite (overbite depth indicator (ODI) 56.84°±9.48° and Frankfort mandibular plane angle (FMA) 31.21°±6.44°) and 90 CBCTs of individuals (mean age 26.87) without an open bite (ODI 62.24°±9.47°, FMA 26.79°±5.81°). Two trained and calibrated orthodontists made all linear, area, and volume measurements on the CBCT records of the upper airways using Planmeca Romexis software. The Mann-Whitney U-test, chi-squared test, and multiple linear regression were applied. Significance was set at P<0.05.

RESULTS

There were no differences in linear or volume measurements between groups, but there was a greater area in the open bite group (greater mean difference between groups 928.3 mm²) than the control group. No variable influenced nasopharyngeal airway volume, but ANB angle affected oropharyngeal airway volume (β=-623.87) and total airway volume (β=-651.48).

CONCLUSIONS

Orthodontists should be aware that the airways diagnosis can vary depending on the measurement approach used, the volumetric method being the gold standard. The pharyngeal airway volume was similar in individuals with vs. without an open bite and is mainly influenced by ANB angle in both groups.