Three-dimensional analyses of palatal morphology and its relation to upper airway area in obstructive sleep apnea

Palatal Morphology After Treatment of Children With Obstructive Sleep Apnoea Using the Modified Twin-Block Appliance

OBJECTIVE

To investigate changes in the upper maxillary palates of children with obstructive sleep apnoea (OSA) and mandibular retraction who were treated using modified twin-block appliances (MTBAs).

METHODS

Thirty-five OSA children (age: 6-12 years) with mandibular retraction were included as the experimental group and 35 children who were Angle's class I but without mandibular retraction were included as the control group. The experimental group was treated with MTBA. Plaster models were made before the treatment and at the end of the 6-month treatment period. Plaster models of the control group were made at inclusion and after 6 months. Some plaster models were excluded because of damage or their failure to exhibit sufficiently clear marks, which left 26 pairs each for the experimental and control groups. The gender and age of the experimental group were matched with those of the control group at the end of the treatment. Three-dimensional (3D) digital model information was gathered using the external oral scanning model, and the data were extracted and analysed statistically to clarify the morphologic improvement in the maxillopalatine in OSA children treated using MTBAs.

RESULTS

After the OSA children with mandibular retraction were treated with MTBAs, the maxillary intercusp width, intermolar width, anterior palate width, posterior palate width, and surface area and volume of the maxillary palate significantly increased (*P < .05). By contrast, the anterior palatal height-apex level (H3) significantly decreased (*P < .05).

CONCLUSIONS

Compared with the control group, the narrow maxillary arch and basal bone were significantly enlarged after the OSA children with mandibular retraction were treated using MTBAs. The palatal surface area and volume increased, thereby allowing more space for accommodating the tongue and relieving transverse dissonance of the dentition.

Correlation between dental arch form and OSA severity in adult patients: an observational study

BACKGROUND

The role of interdental widths and palatal morphology on the development of obstructive sleep apnea (OSA) has not been well investigated in adult patients yet. The aim of this paper was to assess the morphology of maxilla and mandibular dental arches on three-dimensional (3D) casts and to correlate these measurements with the severity of OSA.

METHODS

Sixty-four patients (8 women and 56 men, mean age 52.4) with a diagnosis of mild-to-moderate OSA were retrospectively enrolled. On each patient, home sleep apnea test and 3D dental models were collected. Apnea-hypopnea index (AHI) and oxygen desaturation index (ODI) were recorded, as well as the dental measurements including inter-molar distance, anterior and posterior widths of maxillary and mandibular arches, upper and lower arch lengths, palatal height, and palatal surface area. The respiratory and dental variables were then correlated.

RESULT

A statistically inverse correlation was found between ODI and anterior width of lower arch, maxillary arch length, palatal height, and palatal area. AHI showed a significant inverse correlation with anterior width of mandibular arch and maxillary length.

CONCLUSION

A significant inverse correlation between maxillary and mandibular morphology and respiratory parameters was shown in the present paper.

Assessment of changes in Streptococcus pyogenes levels using N-acetylgalactosamine-6-sulfatase marker and pharyngeal airway space with appliance therapy in mouth breathers - An ELISA-based study

Background

The frequency of adenotonsillar hypertrophy in mouth-breathing children when compared to the average found in the general population is considered to be higher. Mouth breathing is considered as one of the causative factors for tonsillitis in children. Through continuous irritation on tonsillar wall, tonsils swell up and inflammation develops.

Purpose

The purpose of the study is to evaluate Streptococcus pyogenes count using colony-forming units (CFUs) and N-acetylgalactosamine-6-sulfatase side chain marker on ELISA (enzyme linked immunosorbent assay) in mouth breathers and to establish its correlation with pharyngeal airway space pre- and post-oral screen appliance therapy.

Materials and Methods

A total number of 24 (n) mouth breathers aged between 5 and 12 years were included in the study and given oral screen appliance therapy. The subjects were evaluated for the various parameters before the delivery of a habit-breaking appliance and then reevaluated for the same parameters (presence of S. pyogenes and its counts, size of tonsils, and pharyngeal airway space dimensions) after 6 months of appliance usage.

Results

A statistically significant difference was seen in levels of S. pyogenes using ELISA and CFUs. Furthermore, statistically significant difference was observed in Friedman tonsil scoring and pharyngeal airway space and pre- and post-oral screen appliance therapy.

Conclusion

Oral screen appliance therapy reduced the frequency of occurrence of tonsillitis in mouth breathers by decreasing the counts of S. pyogenes bacteria. Upper and lower pharyngeal airway space dimensions were increased after 6 months of appliance therapy in mouth breathers.

Analysis of maxillary arch morphology and its relationship with upper airway in mouth breathing subjects with different sagittal growth patterns

OBJECTIVE

This three-dimensional cone beam computed tomography(CBCT) study assessed pharyngeal airway and maxillary arch in mouth breathing subjects with different skeletal classifications and analyzed the factors associated with the upper airway morphological variations in mouth breathing (MB) and nasal breathing (NB) subjects.

METHODS

One hundred and five subjects (52 MB and 53 NB children), divided into three skeletal groups: Class I (1° ≤ ANB° ≤ 5°), Class II (ANB° >5°), and Class III (ANB°<1°). An independent t-test and one-way ANOVA test were utilized in the group analysis of normal distributed data. The linear multiple regression test was applied to create a model for the airway volumes based on the maxillary arch parameters in different skeletal groups.

RESULTS

In three skeletal groups, NB individuals had greater oropharyngeal airway volume (OPV) and total pharyngeal airway volume (TPV) than MB. Maxillary arch parameters of intermolar width (IMW), intercanine width (ICW), and maxillary width of canines (MWC) were larger in NB participants than in MB subjects. In the MB group, we discovered that Class II individuals had lower NPV (nasopharyngeal airway volume) than Class I and Class III. MWC was lower in Class II subjects compared to Class I and Class III in both the NB and MB groups.

CONCLUSION

NB individuals had greater pharyngeal airway and maxillary arch parameters than MB subjects. Our model equation revealed that the inter-molar width (IMW) and palatal area (PA) parameters were the strongest predictors of total pharyngeal airway volume (TPV) in the skeletal Class II and Class I groups.

Three-dimensional evaluation of pharyngeal airway and maxillary arch in mouth and nasal breathing children with skeletal Class I and II

Objective

This study aimed to investigate whether the subjects with mouth breathing (MB) or nasal breathing (NB) with different sagittal skeletal patterns showed different maxillary arch and pharyngeal airway characteristics.

Methods

Cone-beam computed tomography scans from 70 children aged 10 to 12 years with sagittal skeletal Classes I and II were used to measure the pharyngeal airway, maxillary width, palatal area, and height. The independent t-test and the Mann–Whitney U test were used for the intragroup analysis of pharyngeal airway and maxillary arch parameters.

Results

In the Skeletal Class I group, nasopharyngeal airway volume (P < 0.01), oropharyngeal airway volume (OPV), and total pharyngeal airway volume (TPV) (all P < 0.001) were significantly greater in subjects with NB than in those with MB. Furthermore, intermolar width, maxillary width at the molars, intercanine width, maxillary width at the canines, and palatal area were significantly larger in subjects with NB than in those with MB (all P < 0.001). In the Skeletal Class II group, OPV, TPV (both P < 0.05) were significantly greater in subjects with NB than in those with MB. No significant differences in pharyngeal airway parameters in the MB group between subjects with Skeletal Class I and those with Skeletal Class II.

Conclusion

Regardless of sagittal Skeletal Class I or II, the pharyngeal airway and maxillary arch in children with MB differ from those with NB. However, the pharyngeal airway was not significantly different between Skeletal Class I and II in children with MB.

Obstructive sleep apnoea syndrome and anatomical factors: possible correlations

OBJECTIVES

The following retrospective study was devised with the aim of evaluating the correlation between OSAS and various anatomical factors.

MATERIAL AND METHODS

Thirty-seven patients over the age of 40 were analyzed, of which 19 were classified as OSAS cases and 18 as control cases. For each, 17 anatomical variables were identified and examined using Invivo Dental software on CBCT scans, WebCeph software on laterolateral teleradiographs, and Rhinoceros 6.0 software on dental casts.

RESULTS

A generalized linear model of all the anatomical factors identified only two statistically significant variables. Specifically, the total volume of the palate displayed a inverse correlation with OSAS, while the distance between the S point and the Go point (S-Go) exhibited a direct correlation with the disease.

CONCLUSION

The likelihood of an individual having OSAS appears to decrease as the volume of the palate increases but increase as the lingual measure S-Go increases.

Obstructive Sleep Apnea, Palatal Morphology, and Aortic Dilatation in Marfan Syndrome Growing Subjects: A Retrospective Study

The main cause of mortality in Marfan syndrome (MS) is aortic disease. Obstructive sleep apnea (OSA) is highly prevalent in MS, and it is also associated with cardiovascular risk and maxillary deformities. The aim of this research was to analyze the possible relations between OSA, palatal morphology, and aortic root diameters in growing subjects. A group of 15 growing subjects with MS and a control group of healthy peers was selected. All of them underwent nocturnal polygraphic monitoring, digital dental casts, and transthoracic echocardiography. The results showed that OSA indexes and aortic diameters were significantly higher in the study group. Transversal palatal dimension was smaller in MS patients. Moreover, OSA severity was not related with maxillary contraction severity in MS. No correlation between OSA severity and increased aortic diameters occurred. A high prevalence of OSA, increased aortic dimensions, and significant contraction of palatal dimensions were observed in MS compared with the control group. None of these single factors may directly be associated with aortic dilation, but together, they might contribute to the development and progression of aortic aneurysm from a young age.

Decreased maxillary sinus volume is a potential predictor of obstructive sleep apnea

OBJECTIVES

To investigate the associations between nasal airway volume and the presence and severity of obstructive sleep apnea (OSA) in adults.

MATERIALS AND METHODS

The medical records of adult patients who visited the sleep clinic at University Hospital between June 2013 and April 2017 and underwent overnight polysomnography for the diagnosis of obstructive sleep apnea were reviewed retrospectively. Using computed tomography, the volumes of the nasal airways and maxillary sinuses were measured, and associations with the presence and severity of OSA were analyzed while controlling for the effects of possible confounders such as lateral cephalometric variables, maxillary widths, tongue/hyoid position, and soft palate dimensions.

RESULTS

Comparison between normal subjects and patients with OSA revealed that the latter had decreased ratios of maxillary sinus volume to whole nasal airway volume (P = .029) than normal subjects. OSA severity was greater in those with inferior positions of the hyoid (P = .010), in older patients (P = .011), and in those with high body mass index (P = .001). The volume of the total nasal airway or maxillary sinuses were not associated with OSA severity.

CONCLUSIONS

A decreased ratio of maxillary sinus volume to whole nasal airway volume is associated with adult OSA. However, OSA severity is not associated with either maxillary sinus volume or whole nasal airway volume.

Dental arch form and interdental widths evaluation in adult Caucasian patients with obstructive sleep apnea syndrome

OBJECTIVE

To evaluate the hypothesis that dental arch form and inter-canine, inter-premolar, and inter-molar widths differ between OSAS patients and non-snoring, non-apneic controls.

METHODS

Dental digital models from 64 OSAS patients and 64 control subjects were used to obtain dental arch forms and to compare them between the two groups. Arch forms were extracted from the lower arch models using a professional graphics program and an orthodontic digital template. Through an orthodontic software, inter-molar, inter-premolar, and inter-canine widths were measured for both upper and lower arches.

RESULTS

The dental arch forms distribution differed between OSAS patients and controls. OSAS patients had reduced inter-canine, inter-premolar, and inter-molar widths for both arches compared to controls.

DISCUSSION

These results suggest that OSAS patients have narrower and more tapered arches than controls. Dental arch morphology and interdental widths differ between OSAS and control groups, supporting the hypothesis that they are an etiological factor.

Three-dimensional morphological evaluation of the hard palate in Korean adults with mild-to-moderate obstructive sleep apnea

Objective

The purpose of this study was to evaluate differences in three-dimensional (3D) morphology of the hard palate between Korean adults with and without mild-to-moderate obstructive sleep apnea (OSA) using cone-beam computed tomographic (CBCT) data.

Methods

The protocol for the two-dimensional (2D) and 3D mathematical modeling was established by analyzing CBCT images of 30 adults with OSA and 30 matched controls without OSA, using MIMICS software. The linear and angular measurements were also determined using this software. The measurements were repeated for 30 palates, by the same operator, to assess reliability.

Results

The palates of OSA patients were higher in the posterior part and narrower in the anterior-superior part than those of the control group (p < 0.05). The nasal cavities of patients with OSA were narrower (p < 0.05) than those of controls. The increasing angle of the first molar palatal root is a compensation of the upper dental arch to improve occlusion. However, for most palatal measurements, there were no significant differences between the OSA and control groups (p > 0.05). The results of 2D and 3D mathematical models were consistent for linear and angular measurements, indicating that 2D and 3D mathematical modeling of the palate is a reliable methodology.

Conclusions

OSA is a multifactorial disease; the palates of adults with mild-to-moderate OSA do not have specific morphological features distinct from those of healthy controls.