Cephalometric evaluation of the airway space and hyoid bone in children with normal and atypical deglutition: correlation study

Effects of Froggy Mouth Appliance in Pediatric Patients with Atypical Swallowing: A Prospective Study

Atypical swallowing has a high incidence in growing subjects. Orthopedic treatment with orthodontic appliances and speech therapy are the main approaches to this problem. The aim of this prospective study was to evaluate the changes in the dental arches induced by one year of treatment with the Froggy Mouth myofunctional appliance designed to correct atypical swallowing. In total, 16 patients with atypical swallowing were instructed to use the Froggy Mouth appliance. A digital intraoral impression was taken at baseline (T0). The Froggy Mouth appliance had to be used for 15 min/day throughout the treatment period. At the end of the first year of treatment (T1), another impression was taken with the same intraoral scanner. Digital casts of the T0 and T1 impressions were obtained using software and the two casts were superimposed to record the following measurements: upper intercanine distance, upper arch diameter, upper arch width, overbite and overjet. The data were statistically analyzed (significance threshold: p < 0.05). Student's t-test was used to compare pre- and post-treatment measurements. Linear regressions were performed to assess the influence of arch width on anterior and posterior diameters. A significant increase was found for the upper arch diameters (p < 0.05), whereas no statistically significant difference was found for the incisor relationship (overjet/overbite) (p > 0.05). To date, the efficacy of this appliance has not been extensively studied. According to the present prospective study, the Froggy Mouth protocol could be a valuable method as a myofunctional therapy for atypical swallowing, but further studies are needed to confirm these preliminary results.

Pharyngeal Airway Space Dimensions and Hyoid Bone Position in Various Craniofacial Morphologies

Objective:

To assess the relationship of pharyngeal airway dimensions and the position of the hyoid bone in several craniofacial morphologies among Nepali adults. To assess the relationship between dimensions of the pharyngeal airway and position of the hyoid bone and compare gender dimorphism.

Materials and Methods:

The cross-sectional observational research comprised lateral cephalograms of 150 subjects aged 16 to 30 years. Samples were separated into three sagittal craniofacial morphological groups based on the ANB (A point, nasion, B point) angle and into gender groups. Different parameters (linear and angular) for measuring dimensions of the pharyngeal airway and position of the hyoid bone were assessed. An ANOVA test and a Pearson correlation test were performed.

Results:

Dimensions of the pharyngeal airway were largest in skeletal Class III when compared to skeletal Class I and Class II subjects, with a lower pharyngeal airway space and the length of the nasal fossa being significantly larger. The hyoid bone was anteriorly and inferiorly placed in Class III skeletal subjects. Males had greater pharyngeal airway dimensions and a hyoid bone positioned more inferiorly and anteriorly. The nasal fossa length had a strong positive correlation with the hyoid bone position vertically.

Conclusion:

There were differences in the dimensions of the pharyngeal airway and position of the hyoid bone in various craniofacial morphologies among Nepali adults. Gender dimorphism was observed in both dimensions of the pharyngeal airway and the position of the hyoid bone.

Short-Term Effects of a Myofunctional Appliance on Atypical Swallowing and Lip Strength: A Prospective Study

Atypical swallowing needs treatment in order to eliminate harmful interferences of the tongue, which prevent the harmonious growth of the stomatognathic system. The purpose of this study was to assess the effects of a functional appliance on the presence of atypical swallowing, analyzing the lip strength and the altered facial mimics. The effects of a myofunctional appliance (the Froggy Mouth) were evaluated on 40 children (6 males; 24 females; mean age 9.6 ± 2.17) with atypical swallowing—with tongue thrust diagnosed by an expert orthodontist—before and during a 6 month treatment. Data were analyzed over time with a paired samples t-test for normally distributed data. After 6 months of treatment, 33 children out of 40 achieved clinical correction of atypical swallowing due to their good compliance, even at an early stage. Seven children showed low compliance and did not obtain any result. Lip strength in compliant subjects went from 190.30 ± 86.04 cN to 489.39 ± 123.36 cN (t = p < 0.001). Facial mimics improved in 28 out of 33 compliant subjects, and four children with the initial diagnosis of labial incompetence achieved correction. This observational study demonstrates the short-term efficacy of this myofunctional appliance in the treatment of atypical swallowing, achieving correction of the facial mimics and labial incompetence with a significant improvement of the lip strength.

Correlation between hyoid bone position and airway dimensions in Chinese adolescents by cone beam computed tomography analysis

This study aimed to investigate the correlation between upper airway dimensions and hyoid bone position in Chinese adolescents based on cone beam computed tomography (CBCT) images. CBCT images from a total of 254 study subjects were included. The upper airway and hyoid bone parameters were measured by Materialism's interactive medical image control system (MIMICS) v.16.01 (Materialise, Leuven, Belgium). The airway dimensions were evaluated in terms of volume, cross-sectional area (CSA), mean CSA, length, anteroposterior dimension of the cross-section (AP), lateral dimension of the cross-section (LAT), and LAT/AP ratio. The hyoid bone position was evaluated using eight linear parameters and two angular parameters. Facial characteristics were evaluated using three linear parameters and three angular parameters. Most hyoid bone position parameters (especially the distance between the hyoid bone and hard palate) were significantly associated with most airway dimension parameters. Significant correlations were also observed between the different facial characteristic parameters and hyoid bone position parameters. Most airway dimension parameters showed significant correlations with linear facial parameters, but they displayed significant correlations with only a few angular facial parameters. These findings provide an understanding of the static relationship between the hyoid bone position and airway dimensions, which may serve as a reference for surgeons before orthodontic or orthognathic surgery.