Effects of maxillary protraction therapy on the pharyngeal airway in patients with repaired unilateral cleft lip and palate: A 3-dimensional computed tomographic study

Comparison of Nasopharyngeal Airway Volume in Cleft Lip and Palate Patients With Normal Individuals Using Cone Beam Computed Tomography

This study aimed to compare nasopharyngeal airway volume in cleft lip and palate patients with normal individuals using Cone Beam Computed Tomography (CBCT). In this cross-sectional study, 40 CBCT scans of 9 to 12-years-old patients were enrolled and divided into 3 groups: normal individuals (n=16), unilateral cleft lip and palate (UCLP, n=14) and bilateral cleft lip and palate patients (BCLP, n=10). Superior and middle pharyngeal airway volumes and nasal width were measured and compared between 3 groups. ANOVA and χ 2 tests were used for statistical comparison. P <0.05 was considered significant. Superior airway volume was not significantly different between the 3 groups ( P =0.36). However, there was a significant difference between the 3 groups regarding middle pharyngeal volume ( P =0.49) and nasal width ( P =0.021). There was not a significant difference in the upper and middle pharyngeal volume and also nasal width between the 2 sexes. Considering different dimensions of evaluation of the pharyngeal airway volume of cleft lip and palate patients, the evaluation of airway volume is essential during orthodontic or orthognathic surgical treatments that expand or protect the maxilla.

Three-dimensional volumetric changes in the airway of growing unilateral complete cleft lip and palate patients after bone-anchored maxillary protraction

INTRODUCTION

This prospective controlled study evaluates volumetric, length, and average cross-sectional area (aCSA) airway changes in growing patients with unilateral complete cleft lip and palate after 1.5 years of bone-anchored maxillary protraction therapy.

METHODS

Thirty-five growing unilateral complete cleft lip and palate patients with maxillary deficiency were included (aged 11.3 ± 0.5 years). Cone-beam computed tomography scans were obtained before bone-anchored maxillary protraction (BAMP) therapy and after 1.5 years. A growing group without cleft (n = 18) patients served as a control group at 1.5 years posttreatment (aged 13.1 ± 1.2 years). Volumetric, length, and aCSA changes of the total airway, nasopharynx (NP), middle pharynx, and inferior pharynx airway were evaluated.

RESULTS

After 1.5 years of BAMP therapy, a significant increase was observed in the total airway volume and the NP (P <0.01). The middle and inferior pharynx showed an insignificant tendency of volumetric increase. Compared with the control group, a significantly larger airway volume could be observed in the total airway and NP (P <0.05). The aCSA of the NP increased significantly compared with pretreatment.

CONCLUSIONS

The total airway and NP volumes significantly increased in growing subjects with cleft lip and palate after 1.5 years of BAMP therapy to a level comparable to a control group without cleft. Volumetric increase in the NP in the BAMP group is mainly attributed to the increase in its cross-sectional area. BAMP can therefore be recommended as an effective therapy for patients with cleft lip and palate with positive effects on airway development.

Upper Airway Changes in Diverse Orthodontic Looms: A Systematic Review and Meta-Analysis

Upper airway assessment is particularly important in the daily work of orthodontists, because of its close connection with the development of craniofacial structures and with other pathologies such as Obstructive Sleep Apnea Syndrome (OSAS). Three-dimensional cone-beam computed tomography images provide a more reliable and comprehensive tool for airway assessment and volumetric measurements. However, the association between upper airway dimensions and skeletal malocclusion is unclear. Therefore, the current systematic review evaluates the effects of different surgical movements on the upper airway. Materials and Methods: Medline (PubMed, OVID Medline, and EBSCO), Cochrane Library (Cochrane Review and Trails), Web of Knowledge (social science, and conference abstracts), Embase (European studies, pharmacological literature, and conference abstracts), CINAHL (nursing and allied health), PsycInfo (psychology and psychiatry), SCOPUS (conference abstracts, and scientific web pages), and ERIC (education) databases were searched. Two authors independently performed the literature search, selection, quality assessment, and data extraction. Inclusion criteria encompassed computed tomography evaluations of the upper airway spaces with retrospective, prospective, and randomised clinical trial study designs. To grade the methodological quality of the included studies a GRADE risk of bias tool was used. Results and conclusion: In total, 29 studies were included. Among these, 17 studies had a low risk of bias, whereas 10 studies had a moderate risk of bias. A meta-analysis was performed with the mean differences using a fixed-effects model. Heterogeneity was assessed with the Q-test and the I2 index. The meta-analysis revealed significant (p ≤ 0.001, 95% confidence interval) increases in upper airway volume after rapid maxillary expansion and surgical advancement for the correction of Class II.

Pharyngeal airway space changes and stability following an extended LeFort-I osteotomy advancement in cleft lip and palate and non-cleft lip and palate patients: A long term comparison study

PURPOSE

The aim of this study was to evaluate effects of extended maxillary advancement osteotomy on pharyngeal airway space (PAS) in mid-facial deficient cleft lip and palate (CLP) patients and mid-facial deficient non-CLP patients.

METHODS

Pharyngeal airway space (PAS) of 10 CLP and 10 non-CLP patients with the mean age of 19 years 10 months was measured on digitized lateral cephalograms taken shortly before maxillary advancement operation with Quadrangular Le Fort I osteotomy (QLF-I) (T0), early post-operative, (T1) and long term post-operative (T2). Two way repeated analysis of variance, independent samples t-test and correlations tests were used for statistical analysis of airway and skeletal changes.

RESULTS

Total PAS depth and area was significantly increased after the advancement and was stable in long term post-operative period for CLP and non-CLP patients. Nasopharyngeal and velopharyngeal airway space depth and area was statistically increased at T1 and T2 for both groups. Oropharyngeal airway depth and area showed no significant statistical difference at any of the time points. The effect of QLF-I osteotomy on (PAS) was similar in both CLP and non-CLP patients.

CONCLUSIONS

Nasopharyngeal, velopharyngeal, and total pharyngeal airway space depth and area increased after maxillary advancement with the QLF-I osteotomy; this increase was stable in long term follow up. Maxillary advancement with the QLF-I technique had no significant effect on oropharyngeal airway space depth and area in both CLP and non-cleft patients.

Velopharyngeal Space Assessment in Patients Undergoing Le Fort 1 Maxillary Advancement

Background:

The effects of maxillary advancement on velopharyngeal anatomy have primarily been studied using lateral cephalometric radiographs. However, with recent advances in orthognathic surgery, there is an increased need for more detailed and precise imaging such as computerized tomographic (CT) scan reconstructions, to help in surgical planning and to measure outcomes. The purpose of this study was to compare the pre- and post-operative velopharyngeal anatomic configuration modifications as measured on CT scans.

Methods:

This is a retrospective cohort study of 44 patients with and without cleft palate who were treated with maxillary advancement. The pre- and post-operative CT scans were compared with respect to pre-established landmarks. Linear distances, cross-sectional areas, and volumes were measured using 3-dimensional CT scan reconstructions.

Results:

For the linear distances measured, a statistically significant difference was found when comparing the pre- and post-operative measures of the narrowest part of the nasopharynx and the narrowest part of the retropalatal airway space (P = 0.001 and 0.026, respectively). Retropalatal cross-sectional areas, nasopharyngeal cross-sectional areas, and the volumetric assessment of the nasopharyngeal space showed no statistically significant differences when comparing pre- and post-operative scans (P < 0.05). Mean changes in the measures did not differ over time (pre- and post-operative) depending on whether there was a prior history of cleft palate repair.

Conclusions:

Although structural modifications of the pharyngeal space are inherent to maxillary advancement, its surface area and volume do not significantly change. The use of 3-dimensional reconstruction using CT scans should be the first choice for evaluation of the upper airway.

Evaluation of nasal airflow resistance of operated unilateral cleft lip and palate surgery patients compared with skeletal class III individuals

OBJECTIVE

The purpose of this study was to measure the nasal airflow resistance of operated unilateral cleft lip and palate (UCLP) patients using the anterior rhinomanometry method compared with non-cleft skeletal class III individuals with isolated maxillary hypoplasia serving as the control group.

MATERIAL&METHODS

Sixteen UCLP patients who have undergone lip and palate reconstructions and alveolar cleft grafting but not advanced surgeries as the study group and 16 non-cleft skeletal class III participants as the control group (corresponded for age and sex to the study group) were included in this prospective study. All of the patients had class III occlusion due to isolated maxillary hypoplasia. Nasal airflow was measured with anterior rhinomanometry (in ml/sec) for each nostril separately. For evaluation of nasal side subgroups of the UCLP group for nasal resistance, the cleft sides and non-cleft sides of individuals were examined in two separate groups. The nasal side resistance of the control group was evaluated as the average of both nasal side resistances. The nasal resistances for nasal sides and total nasal resistance were measured in Pa/L/sec. The observed data were analyzed using Kolmogorov-Smirnov test used for normality, and the Student t-test and Mann Whitney U test used to determine the differences between the groups. P values of <0.05 were considered statistically significant.

RESULTS

As the primary outcome of this study, it was found that both the cleft sides and non-cleft sides of the UCLP individuals had statistically significantly higher nasal resistance than the healthy skeletal class III control group (p < 0.05). It was revealed that the cleft side had more nasal resistance than the non-cleft side for both inspiration and expiration, but the results were not statistically significant (p = 0.41/p = 0.28).

CONCLUSION

The results showed that operated UCLP patients have nasal resistance and breathing problems, even when lip, palate, and alveolar cleft operations have been performed.

Maxillary Protraction Therapy in Class III Patients With and Without Cleft Lip and Palate: An Interim Report of a Prospective Comparative Study

OBJECTIVE

To investigate and compare the effects of maxillary protraction therapy on Class III patients with unilateral cleft lip and palate (UCLP) and Class III patients with noncleft.

DESIGN

Prospective controlled clinical trial.

PATIENTS

Twenty-six Class III patients with UCLP (mean age: 10.32 ± 1.29 years) and 26 Class III patients with noncleft (mean age: 9.82 ± 1.03 years) were included and treated with maxillary protraction therapy.

INTERVENTIONS

Maxillary protraction therapy was performed with an intraoral Hyrax appliance and extraoral facemask. Cone beam computed tomography scans were taken before and after treatment. Pretreatment skeletal and dental characteristics and treatment changes were analyzed and compared.

RESULTS

The average treatment duration was 18.44 ± 4.16 months in the UCLP group, which was substantially longer than the 12.46 ± 4.03-month average treatment duration in the noncleft group (P < .001). No significant difference was found in the maxillary changes (length, advancement of point A, and SNA angle) and improvement of intermaxillary relationship (ANB angle) between the 2 groups. The UCLP group had 1.40° more mandibular clockwise rotation (P = .034). Regarding dental changes, the UCLP group had more upper incisor proclination (P = .006) and less lower incisor retroclination (P = .023).

CONCLUSIONS

Approximately extended maxillary protraction therapy in patients with UCLP could be as effective as in patients with noncleft. Further study is required to follow patients until completion of growth to elucidate the long-term stability of the treatment.

Three-Dimensional Analysis of the Pharyngeal Airway Volume and Craniofacial Morphology in Patients With Bilateral Cleft Lip and Palate

OBJECTIVE

This study aimed to determine the correlations between the craniofacial morphology and pharyngeal airway volume in patients with complete bilateral cleft lip and palate (BCLP).

DESIGN

Retrospective study.

SETTING

Tertiary hospital.

PARTICIPANTS

Twenty-seven patients with complete BCLP and 27 class I control patients, aged 10 to 14 years.

MAIN OUTCOME MEASURE

The pharyngeal airway volume and craniofacial morphology were evaluated using cone-beam computed tomography. Measurements were compared between groups and any correlations were identified.

RESULTS

A significantly smaller total pharyngeal airway volume (TPV), oropharyngeal airway volume, and upper (UOPV) and lower (LOPV) oropharyngeal airway volume were found in patients with BCLP than in class I control patients, with no difference in the nasopharyngeal volume between groups. Furthermore, the craniofacial morphology measurements of N-Me, S-Go, Or-C, Ptm-C, Me-C, Co-Go, Go-Me, Ptm-Or, N-S-Ar, and Ar-Go-Me significantly differed between the BCLP and control groups (all P < .05). Multiple regression analysis indicated that Ptm-C and Me-C; Ptm-C, Or-C, and Me-C; and Me-C explained 20.3%, 38.9%, and 17.1% of the variations in TPV (P = .025), UOPV (P = .002), and LOPV (P = .018), respectively.

CONCLUSIONS

Total pharyngeal airway volume, TPV, OPV, UOPV, and LOPV were significantly smaller in patients with BCLP than in class I controls. In patients with BCLP, the maxilla showed inhibited sagittal development and a retrograde position; moreover, the pharyngeal airway volume was weakly associated with the position of the maxilla and mandible relative to the coronal plane.

Immediate and late follow-up effects of class III early correction in cleft lip and palate patients treated with maxillary protraction

Abstract Introduction There is no consensus about the immediate and latte follow-up effects of maxillary protraction in cleft lip and palate patients. Objective To evaluate the stability of Class III early treatment in cleft lip and palate patients through maxillary expansion and protraction. Material and method The sample consists in three lateral cephalometric radiographs of 28 patients (mean pre-treatment age of 6.7±1.8 years) who presented cleft lip and palate and were treated with maxillary expansion and Petit facial mask. The angular (SNA, SNB, ANB, SN.GoGn, FMA, Z Angle) and linear (overjet, Co-A, Co-Gn, Nperp-A, Nperp-Pg, AO-BO) cephalometric measures were evaluated through the Dolphin® software, in three moments: T0 (initial), T1 (after treatment), and T2 (follow-up). Data were submitted to the analysis of variance (ANOVA) and Tukey-Kramer test. The correlation between cephalometric measures and patient’s age was determined by Pearson’s chi-squared test. Result The SNA, ANB, and AO-BO measures increased considerably (p<0.05), and they did not present any differences compared to the initial ones after the follow-up time. The overjet measure increased (p<0.05) after treatment and, even with its decrease at the follow-up time, it was still higher than at the beginning (p<0.05). The Z angle showed improvement with treatment and remained stable at the follow-up time. Conclusion After treatment (maxillary expansion associated with protraction), there was a skeletal pattern improvement. During the follow-up period, those alterations decreased to a measure close to the beginning. There was an improvement in the dental pattern and facial profile that continued in the follow-up period.

Effect of maxillary expansion and protraction on the oropharyngeal airway in individuals with non-syndromic cleft palate with or without cleft lip

Introduction

The aim of this study was to evaluate three dimensionally the effect of the combined maxillary expansion and protraction treatment on oropharyngeal airway in children with non-syndromic cleft palate with or without cleft lip (CP/L).

Methods

CBCT data of 18 preadolescent individuals (ages, 8.4 ± 1.7 years) with CP/L, who underwent Phase I orthodontic maxillary expansion with protraction, were compared before and after treatment. The average length of treatment was 24.1± 7.6 months. The airway volume and minimal cross-sectional area (MCA) were determined using 3DMD Vultus imaging software with cross-sectional areas calculated for each 2-mm over the entire length of the airway. A control group of 8 preadolescent individuals (ages, 8.7 ± 2.6 years) with CP/L was used for comparison.

Results

There was a statistically significant increase in pharyngeal airway volume after phase I orthodontic treatment in both groups, however, there was no statistically significant change in minimal cross-sectional area in neither study nor control group.

Conclusion

The findings showed that maxillary expansion and protraction did not have a significant effect on increasing oropharyngeal volume and MCA in patients with CP/L.

Three-dimensional assessment of the pharyngeal airway in Japanese preschoolers with orofacial clefts

OBJECTIVES/HYPOTHESIS

Individuals with orofacial clefts often experience respiratory problems because of nasopharyngeal abnormalities. Pharyngeal airway morphology is thought to differ among the various cleft types. We measured three-dimensional (3D) airway volume using cone-beam computed tomography (CBCT) analysis to evaluate and compare pharyngeal airways in Japanese preschoolers with and without orofacial clefts.

STUDY DESIGN

Retrospective case-control study.

METHODS

We enrolled 83 subjects (37 boys, 46 girls; mean age = 4.66 ± 0.56 years) with nonsyndromic orofacial clefts and 16 noncleft healthy subjects (seven boys, nine girls; mean age = 5.30 ± 0.52 years) as controls. The subjects were divided into five groups. Four groups were based on the cleft type: isolated cleft palate, unilateral cleft lip and alveolus), unilateral cleft lip and palate, and bilateral cleft lip and palate. The fifth group included the noncleft controls. All subjects were examined with CBCT, and the 3D airway volume was measured. We analyzed group differences statistically using analysis of covariance with the Bonferroni post hoc pairwise comparison tests for the corrected means.

RESULTS

Compared with the noncleft group, each cleft group exhibited significantly decreased total and nasal airway volumes and increased superior and inferior pharyngeal airway volumes. The differences were all statistically significant.

CONCLUSIONS

Our findings suggest that anatomical differences exist in pharyngeal airway volumes among various cleft groups and in those without a cleft.

LEVEL OF EVIDENCE

3b Laryngoscope, 130:533-540, 2020.

Long-term stability of maxillary protraction therapy in Class III patients with complete unilateral cleft lip and palate

OBJECTIVES

This study evaluated the long-term stability of maxillary protraction (MP) in patients with complete unilateral cleft lip and palate (UCLP) and identified factors influencing relapse and long-term outcomes.

MATERIALS AND METHODS

Twenty-three adolescents with UCLP who underwent MP therapy were recalled when craniofacial growth was close to completion. Subjects exhibiting reverse/positive overjets were assigned to unstable/stable groups. Lateral cephalometric measurements were made before treatment (T0), after active treatment (T1), and at the end of the growth spurt (T2).

RESULTS

About 63% of the subjects exhibited positive overjets during follow-up. The unstable group demonstrated higher B-x and Co-Gn distances than the stable group (both P < .05) at T0. More short-term (T0-T1) sagittal advancement of point A (A-y) was evident in the unstable group than in the stable group ( P < .05), but no long-term difference was apparent between the two groups ( P = .481). During the posttreatment period (T1-T2), the SNA angle and maxillary incisor protrusion (U1-SN angle) were considerably lower in the unstable group than in the stable group (both P < .05). Overall, the unstable group exhibited a lower increase in the vertical extent of point A (A-x) than the stable group from T0 to T2 ( P < .05).

CONCLUSIONS

In the long term, MP affords favorable maxillary advancement in patients with UCLP. A mandibular excess at T0 and vertical maxillary hypoplasia may contribute to the long-term relapse of a reverse overjet.