Immediate impact of rapid maxillary expansion on upper airway dimensions and on the quality of life of mouth breathers

Medium-term effects of rapid maxillary expansion on nasal cavity and pharyngeal airway volumes considering age as a factor: A retrospective study

OBJECTIVES

The medium-term effects of rapid maxillary expansion (RME) on nasal cavity (NC) and upper airway (UA) dimensions based on chronological age are still unclear. This retrospective study evaluated the medium-term changes occurring in the NC and pharyngeal airways (PA) after RME in two distinct age-based cohorts of patients.

METHODS

This retrospective study included 48 subjects who underwent RME grouped in two cohorts: a 6-9-year-old group (EEG group: early expansion group - 25 subjects) and an 11-14-year-old group (LEG group: late expansion group - 23 subjects). NC and PA volumes were analyzed from CBCT imaging segmentation before RME (T0) and twelve months after RME (T1). The amount of maxillary expansion (PW) and minimal cross-sectional area (CSmin) were also considered.

RESULTS

All PAs' volumetric sub-regions, CSmin and PW showed a significant volumetric increment (p < 0.05). Inter-group comparisons showed significant differences (p < 0.05) for nasopharynx and CSmin parameters (p < 0.05), while no significant changes were recorded for the other UA's sub-regions and PW (p > 0.05). According to a deviation analysis, part of the UA increase (more marked for the nasopharynx area) may have occurred due to reduced adenotonsillar tissues, which were larger in the EEG group.

CONCLUSIONS

Twelve months after treatment, clinicians should not expect changes in the UAs dimensions to be solely related to treatment effects of RME; instead, normal craniofacial growth changes and spontaneous regression of the adenotonsillar tissue could represent the most significant factors influencing UAs changes.

CLINICAL SIGNIFICANCE

From the clinical perspective, the results of the present study encourage caution when considering the therapeutic effects of RME on airways dimensions.

Breathing changes following mini-implant-supported maxillary skeletal expander treatment in late adolescent or adult patients : Assessment of objective and subjective functional breathing changes

PURPOSE

The aim of this study was to assess objective and subjective breathing changes in adult patients who underwent maxillary skeletal expansion with the mini-implant-supported maxillary skeletal expander (MSE).

METHODS

Twenty-nine patients (mean age 18.1 ± 4.3 years) who underwent expansion using the MSE were compared pre- and posttreatment and with a control group (mean age 19.9 ± 2.6 years) to assess objective and subjective functional breathing changes. Objective measurements of the airway including peak nasal inspiratory flow (PNIF) and peak oral inspiratory flow (POIF) were measured utilizing the In-Check medical device (Clement Clarke, Harlow, United Kingdom). Patients reported subjective breathing assessment utilizing the visual analog scale (VAS). Intragroup comparisons were performed with Wilcoxon tests and intergroup comparison with Mann-Whitney U tests. Spearman correlation coefficients were calculated among the studied variables (P < 0.05).

RESULTS

Following MSE treatment, there were significantly higher values for PNIF total (P < 0.0001), PNIF right (P < 0.0001), PNIF left (P < 0.0001), and POIF (P < 0.01) compared to pretreatment and control group results. Also, patients reported a significant decrease in troubled breathing as measured by the VAS for breathing through the right nostril (P < 0.01), left nostril (P < 0.001), and both nostrils (P < 0.01). Comparing the objective and subjective variables for both the pre-MSE or post-MSE groups, the results indicated no significant correlation between total PNIF and total VAS. However, the values had significant correlations between PNIF and VAS on each side when the patients were asked to block one nostril.

CONCLUSIONS

Objective functional breathing measurements were increased immediately after treatment with MSE. Subjective functional breathing measurements changes were significantly higher after MSE treatment and compared with the control group. MSE presents a nonsurgical alternative to achieving orthopedic expansion in adult patients which may provide a benefit for patients with nasal airway obstruction.

Interprofessional collaboration in Paediatric Obstructive Sleep Apnoea (POSA) treatment: Assessment of professional orientation levels amongst otolaryngologists in South India

Objective

The primary goal was to assess the knowledge, attitude and practice among otorhinolaryngologists regarding orthodontic intervention for Paediatric Obstructive Sleep Apnoea (POSA).

Methods

An online survey was conducted by sending an email invitation to members of The Association of Otorhinolaryngologists of Karnataka, India. A total of 141 otorhinolaryngologists participated in the survey.

Results

Most of the participants (70.2%) agreed that orthodontic interventions help in opening up the airway, but very few knew about its application in nasal obstruction management.

Conclusion

Otorhinolaryngologists are aware of dental effects of POSA and they believe that an interprofessional team is essential for its management. This learning can also be used to initiate interprofessional collaborations and academic and curricular improvisations for enhanced health outcomes.

Effects of twin-block appliance on upper airway parameters in OSA children with class II malocclusion and mandibular retrognathia: a CBCT study

Twin-block appliance had been advocated as a potential treatment option in paediatric obstructive sleep apnoea (OSA) due to their favourable effect in enhancing upper airway parameters and improving OSA symptoms. The aim of this study was to evaluate the effect of twin-block appliance therapy on upper airway parameters/dimensions and the apnoea-hypopnea indexes (AHIs) in OSA children with class II mandibular retrognathic skeletal malocclusion using cone-beam computed tomography. This prospective longitudinal study comprised 34 polysomnography-proven OSA growing children with class II mandibular retrognathic skeletal malocclusion between the ages of 8 and 12 years who had completed myofunctional twin-block therapy and matched corresponding controls. The upper airway was segmented into the nasopharynx, oropharynx, and hypopharynx, and the effect of twin-bock treatment on upper airway parameters/dimensions was assessed pre- and posttreatment using CBCT analysis, while a second standard overnight PSG was performed to determine changes in the AHI. At the nasopharynx level, minimal (nonsignificant) increases in all variables were observed within the twin-block group and between the groups (P > 0.05). At the level of the oropharynx, all variables increased significantly in the treatment group and between groups (P < 0.001), but these increases were nonsignificant in the control group. At the level of the hypopharynx, only the minimum cross-sectional area (MCA) increased significantly in the treatment group (P = 0.003). The change in MCA was also significant between the groups (P = 0.041). In addition, the upper airway length increased significantly in the twin-block group (P = 0.0154), and the AHI decreased by 74.8% (P < 0.001).

CONCLUSION

Correction of class II mandibular retrognathic skeletal malocclusion with twin-block appliance resulted in a significant increase in upper airway volume, MCA, anteroposterior and lateral distances of the MCA at the level of the oropharynx, MCA at the level of the hypopharynx and upper airway length, and a significant decrease in AHI, but it had no effect on nasopharynx parameters.

WHAT IS KNOWN

• CBCT imaging has been shown to be an effective and precise diagnostic tool for analyzing the upper airways and craniofacial structures. • Twin block appliance may be an effective treatment modality in children with OSA.

WHAT IS NEW

• Minimal cross-sectional area of upper ways may be the most relevant potential parameter when explaining how the upper airway anatomy plays role of in the pathogenesis of pediatric OSA. • Twin block appliance induced favorable changes in upper airway morphology (oropharynx area mainly) and respiratory parameters in OSA children with class II malocclusion.

Morpho-Volumetric Changes of the Pharyngeal Airway With Traumatic Maxillofacial Injuries: A Retrospective Radiographic Study

BACKGROUND

When dealing with traumatized patients, it is crucial to prioritize securing their airway. However, intubating someone who has sustained significant facial injuries can pose difficulties, as the narrow and altered shape of their upper airway may impede their ability to open their mouth. In light of this, the purpose of this study is to evaluate the volumetric and morphological alterations to the upper airway resulting from facial trauma by utilizing computed tomography (CT) scans.

METHOD

This is a single-centered retrospective analytical study. This study included CT scans of patients with traumatic facial injuries admitted to King Fahad Hospital in Madinah, Saudi Arabia. Study variables included age, gender, body mass index (BMI), fractured bones, airway symmetry, and airway volume. Using the 3D Slicer software (Slicer Community, USA), a three-dimensional model of the pharyngeal airway was constructed from the CT scan to evaluate symmetry and volume. IBM SPSS Statistics for Windows, version 23 (released 2013; IBM Corp., Armonk, New York, United States) was used to analyze data.

RESULTS

Among the screened scans, 136 cases with traumatic facial injuries were included in the study. Age ranged from four to 91 years, with a mean of 28.26 (±14.9). Mandibular and zygomatic fractures were the most common, with 71 (52.2%) and 69 (50.7%) cases, respectively. The pharyngeal airway was symmetric in 111 (81.6%) cases and not symmetric in the other 25 (18.4%) cases. A significant association was found between the side of the fracture and airway asymmetry in mandibular fractures (p-value = 0.03). The total airway volume in the displaced mandibular fractures showed a statistically significant decrease (p-value = 0.019). The fracture sites were not statistically linked to airway asymmetry except for parasymphyseal and symphyseal fractures, with a p-value of 0.038 and 0.041, respectively.

CONCLUSION

The study findings suggest that the pharyngeal airway is not usually compromised in most facial bone fractures; however, bilateral displaced mandibular fractures have the potential to diminish the pharyngeal airway volume, especially in fractures involving the symphysis and parasymphysis area.

Three-dimensional evaluation of the association between tongue position and upper airway morphology in adults: A cross-sectional study

Objective

This study aimed to evaluate the association between low tongue position (LTP) and the volume and dimensions of the nasopharyngeal, retropalatal, retroglossal, and hypopharyngeal segments of the upper airway.

Methods

A total of 194 subjects, including 91 males and 103 females were divided into a resting tongue position (RTP) group and a LTP group according to their tongue position. Subjects in the LTP group were divided into four subgroups (Q1, Q2, Q3, and Q4) according to the intraoral space volume. The 3D slicer software was used to measure the volume and minimum and average cross-sectional areas of each group. Airway differences between the RTP and LTP groups were analyzed to explore the association between tongue position and the upper airway.

Results

No significant differences were found in the airway dimensions between the RTP and LTP groups. For both retropalatal and retroglossal segments, the volume and average cross-sectional area were significantly greater in the patients with extremely low tongue position. Regression analysis showed that the retroglossal airway dimensions were positively correlated with the intraoral space volume and negatively correlated with A point-nasion-B point and palatal plane to mandibular plane. Males generally had larger retroglossal and hypopharyngeal airways than females.

Conclusions

Tongue position did not significantly influence upper airway volume or dimensions, except in the extremely LTP subgroup.

Treatment of Class II malocclusion with anterior open bite and posterior crossbite with the aid of mini-implants in a patient with Down syndrome: Clinical case report

OBJECTIVE

We report the orthodontic treatment of a class II malocclusion with anterior open bite and posterior crossbite in a patient with Down syndrome (DS) treated with mini-implants.

METHODS

Treatment began with rapid maxillary expansion with a Haas appliance, followed by dental alignment and leveling with a fixed appliance and the correction of class II dental relationships with the use of orthodontic mini-implants associated with a sliding jig.

RESULTS

The results obtained at the end of the treatment were satisfactory, with improvements in occlusion, including bite closure; maxillary expansion; and the correction of dental relationships.

CONCLUSION

When well-planned, orthodontic treatment in a patient with DS achieves satisfactory results from a skeletal, occlusal, and facial perspective.

Upper airway changes after rapid maxillary expansion: three-dimensional analyses

The objective of this study was to evaluate volumetric changes in the upper airway using Cone Beam Computed Tomography (CBCT) in orthodontic patients with maxillary transversal hypoplasia undergoing maxillary disjunction. The influence of factors such as sex, age, and growth pattern on airway volumetric changes was also assessed. The sample consisted of 50 growing patients from the dental clinic of Cardenal Herrera CEU University of Valencia. Airway volume was measured in mm3 before treatment (T0) and after palatal disjunction (T1). The final sample included 37 subjects in the treatment group and 13 in the control group. The volume gained exclusively from the disjunction treatment was determined to differentiate it from natural growth. The control group showed a mean volume increase from 10,911.3 ± 1,249.6 mm3 to 13,168.9 ± 1,789.7 mm3, representing a mean increase of 2,257.6 mm3 or + 20.9%. The treatment group exhibited an increase from 14,126.3 ± 4,399.8 mm3 at T0 to 18,064.1 ± 4,565.9 mm3 at T1, corresponding to a gain of 3,937.8 mm3 or + 31.8%. Significant differences in airway volume were observed after palatal disjunction compared to the control group. The expansion of the maxilla led to a significant increase in airway volume in the treated patients, estimated at 5,183 mm3 (+ 41.5%).

Correlation Between Third Molar Mineralization and Midpalatal Suture Maturity: A Cone Beam Computed Tomography Study

BACKGROUND Midpalatal suture ossification varies in patients of different ages, which can lead to making inaccurate presumptions when considering effective treatment timing based on chronological age. Chronological age provides only general information, whereas dental development correlates with skeletal growth, which suggests that tooth mineralization could be considered to be a precise criterion for determining the midpalatal suture's maturity. The present study was conducted to investigate the association between third-molar mineralization and midpalatal suture's maturation stages using cone-beam computed tomography (CBCT) images. MATERIAL AND METHODS The study involved 97 CBCT images of patients aged 8-37 years with normal growth and development. Subjects with cleft lip and palate, caries treatment, or present cavities in the third molars were not included in the study. The stages of midpalatal suture ossification were evaluated according to the protocol suggested by Angelieri et al, and the third-molar mineralization degree was measured by the Demirjian index. Statistical analysis was performed to evaluate correlations between the variables. RESULTS Patients with advanced third-molar mineralization stages were found to have greater midpalatal suture maturity. A statistically significant positive correlation was found between the stages of third-molar mineralization and midpalatal suture maturation (R=0.814, P<0.01). Third-molar development was also found to be associated with chronological age (R=0.883, P<0.01). CONCLUSIONS A measure of third-molar mineralization does not allow for accurate determination of the midpalatal suture maturation stage.

A roadmap of craniofacial growth modification for children with sleep-disordered breathing: a multidisciplinary proposal

Craniofacial modification by orthodontic techniques is increasingly incorporated into the multidisciplinary management of sleep-disordered breathing in children and adolescents. With increasing application of orthodontics to this clinical population it is important for healthcare providers, families, and patients to understand the wide range of available treatments. Orthodontists can guide craniofacial growth depending on age; therefore, it is important to work with other providers for a team-based approach to sleep-disordered breathing. From infancy to adulthood the dentition and craniofacial complex change with growth patterns that can be intercepted and targeted at critical time points. This article proposes a clinical guideline for application of multidisciplinary care with emphasis on dentofacial interventions that target variable growth patterns. We also highlight how these guidelines serve as a roadmap for the key questions that will influence future research directions. Ultimately the appropriate application of these orthodontic techniques will not only provide an important therapeutic option for children and adolescents with symptomatic sleep-disordered breathing but may help also mitigate or prevent its onset.

Comparison of rapid versus slow maxillary expansion on patient-reported outcome measures in growing patients: a systematic review and meta-analysis

BACKGROUND

No systematic review and meta-analysis are present in the literature comparing patient-reported outcome measures (PROMs) in rapid maxillary expansion (RME) versus slow maxillary expansion (SME) in growing patients.

OBJECTIVE

The objective of this systematic review was to compare PROMs in RME versus SME in growing patients.

MATERIALS AND METHODS

Electronic search in PubMed (MEDLINE), Cochrane Library, Scopus, Embase, Web of Science, and OpenGrey was conducted. Only RCTs were included. Inclusion criteria were: growing patients in the mixed dentition or early permanent dentition, mild-to-moderate maxillary transverse deficiency, dental crowding, treatment with fixed expanders for rapid and slow maxillary expansion. Risk of bias was assessed using RoB 2. GRADE statement was performed. The mean of the differences (MD) and the risk ratio (RR) were used for the aggregation of data. A random effect model was applied.

RESULTS

Two articles with a total of 157 patients were finally included in the systematic review and meta-analysis. One article was at low risk of bias, while one was at risk of bias with some concerns. Pain presence was less, though not statistically significant, in SME patients (RR = 2.02, 95%CI from 0.55 to 7.49, P = 0.29, I² = 95%, 2 studies, GRADE very low). Pain intensity was significantly lower in SME appliance in the first week of treatment (pooled MD = 0.86 favoring SME, 95%CI from 0.47 to 1.26, P < 0.0001, I² = 6%, 2 studies, GRADE moderate). There were no significant differences between the two groups in difficulty in speaking, difficulty in swallowing, hypersalivation, difficulty in hygiene, and patient and parent satisfaction.

CONCLUSIONS

Pain intensity was significantly lower in SME compared to RME during the first week of treatment. For the following weeks, there were no differences in pain between the two protocols.

Rapid Maxillary Expansion (RME): An Otolaryngologic Perspective

Background. To evaluate the possible effects of Rapid Maxillary Expansion (RME), such as nasal breathing problems, middle ear function, Obstructive Sleep Apnea (OSA) in the otolaryngology field. RME has already been introduced in orthodontics to expand the maxilla of young patients affected by transversal maxillary constriction. Methods. A literature search was performed using different databases (Medline/PubMed, EMBASE, and CINAHL), from May 2005 to November 2021, according to the PRISMA guidelines. Results. The application of RME in children has shown good results on nasal function, reducing nasal resistances, independently from a previous adenotonsillectomy. These results are not only related to the increasing of nasal transverse diameters and volume, but also to the stiffening of airway muscles, enabling the nasal filtrum function and avoiding mouth opening, thereby decreasing respiratory infections. Positive effects have also been reported for the treatment of conductive hearing loss and of OSA, with the reduction of Apnea Hypopnea Index (AHI), possibly due to (i) an increased pharyngeal dimensions, (ii) a new tongue posture, and (iii) reduced nasal respiratory problems. Conclusions. Otolaryngologists should be aware of the indications and benefits of the RME treatment, considering its possible multiple beneficial effects.

Rapid Maxillary Expansion and Upper Airway Volume: Systematic Review and Meta-analysis on the Role of Rapid Maxillary Expansion in Mouth Breathing

Objective

Rapid maxillary expansion (RME) has been extensively used in orthodontic practice for over a century, and it is claimed to benefit upper airway morphology. However, its effect in actually alleviating mouth breathing has remained unexplored. This systematic review was planned with an objective to provide a comprehensive synthesis of the effects of RME on upper airway volume and most importantly, its role in alleviating mouth breathing.

Methods

A literature search of electronic databases were done for the time period of 2000-2018. Randomized controlled trials (RCTs) and non-RCTs conducted on 8-15-year-old children who received bonded or banded RME and upper airway measured using three-dimensional (3D) imaging were included.

Results

Twelve studies (two RCTs, nine nonrandomized clinical trials, and one non-RCT) were included in this systematic review, and nine studies were included for meta-analysis. Among the evaluated parameters, nasal cavity volume showed a significant increase which was maintained even after the retention phase, whereas nasopharyngeal and oropharyngeal volume did not report a significant change.

Conclusion

Based on this systematic review, it can be concluded that RME causes a significant increase in nasal cavity volume, but its effect on nasopharyngeal and oropharyngeal volume is not statistically significant in majority of studies. This increase in volume may not be considered as an equivalent for enhancement of airway and function unless proven so. In order to establish its significance in the improvement of breathing, it is necessary to conduct more well-designed RCTs with samples actually comprising mouth breathers.

How to cite this article

Balasubramanian S, Kalaskar R, Kalaskar A. Rapid Maxillary Expansion and Upper Airway Volume: Systematic Review and Meta-analysis on the Role of Rapid Maxillary Expansion in Mouth Breathing. Int J Clin Pediatr Dent 2022;15(5):617-630.

[Dimensions of the upper airways and its impact on the dentoalveolar system development]

Due to the high mobility and variability of bone structures and soft tissues surrounding the upper respiratory tract, the exact boundaries for measuring and normalizing the size of the respiratory tract have not yet been determined. Studies have determined the relationship between the narrowing of the upper jaw and a decrease in the transverse dimensions of the airways, as well as a positive effect in changing the size of the airways after orthodontic treatment and/or orthognathic surgery. Nevertheless, the results of research in this area may differ greatly from different specialists, which indicates that the topic is poorly studied and it is necessary to continue and expand the range of scientific works to assess the state of the upper respiratory tract and their relationship with the orthodontic status.

Effect of treatment of transverse maxillary deficiency using rapid palatal expansion on oral health-related quality of life in children: A randomized controlled trial

INTRODUCTION

This trial aimed to longitudinally evaluate the effect of the treatment of transverse maxillary deficiency using rapid palatal expansion (RPE) on self-perceived oral health-related quality of life (OHRQOL) in children.

METHODS

Eighty participants aged 8-10 years with transverse maxillary deficiency and bilateral posterior crossbite were randomly assigned to 2 groups (n = 40 each): a group treated with RPE using hyrax-type appliances and a nontreated control group. OHRQOL was assessed by using the Child Perceptions Questionnaire for 8-10-year-olds at 4 times: before RPE, during RPE (T₁), at the end of RPE (T₂), and 1 month after the appliance removal (T₃). Generalized mixed models were used for data analysis (α = 0.05).

RESULTS

Both groups exhibited similar demographic characteristics and OHRQOL scores at baseline. All participants completed the study. RPE had a time-dependent effect on OHRQOL. At T₁ and T₂, this therapy is expected to increase the overall OHRQOL scores by 1.17 times (ie, ∼17% increase; T₁ 95% confidence interval [CI], 1.08-1.26; T₂ 95% CI, 1.09-1.27; P = 0.001). In contrast, the overall OHRQOL scores at T₃ are expected to be 0.28 times the baseline scores (ie, ∼72% reduction; T₃ 95% CI, 0.26-0.31; P = 0.001). All individual domains of the OHRQOL evidenced a positive impact of treatment at T₃ (P = 0.001). Only the oral symptoms and social well-being domains showed a significantly negative impact of the treatment at T₁ and T₂.

CONCLUSIONS

Correction of the transverse maxillary deficiency by RPE in children aged 8-10 years improves OHRQOL. There is a temporary worsening of OHRQOL during the treatment of this condition using RPE.

REGISTRATION

This trial was not registered.

PROTOCOL

The protocol was not published before trial commencement.

FUNDING

This study was financed by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brazil, Financing Code 001.

Influence of rapid maxillary expansion on nocturnal enuresis in children

OBJECTIVES

To evaluate the influence of rapid maxillary expansion (RME) on nocturnal enuresis (NE) in children to discuss whether RME can be indicated as an alternative treatment for NE in those patients.

MATERIALS AND METHODS

An electronic search was performed in the following databases: PubMed/MEDLINE, Cochrane Library, Scopus, Science Direct, Google Scholar and LILACS. The literature review was blindly performed by two reviewers. References of each selected study were manually searched to identify articles that were not found by the electronic search. Kappa statistics were used to analyze interexaminer agreement after the selection of the articles. After reading the selected full-text articles, the studies that met the inclusion criteria were assessed qualitatively using the Risk Of Bias In Non-randomized Studies of Interventions (ROBINS-I) and the Revised Cochrane risk-of-bias tool for randomized controlled trials-2 (RoB 2). The certainty level of evidence was assessed through the Grading of Recommendations, Assessment, Development and Evaluation tool. Kappa tests were used to analyze the interexaminer concordance level after the quality assessment of the studies.

RESULTS

A total of 488 articles were found; however, after applying the inclusion and exclusion criteria, only 8 studies were selected for the systematic review. A low certainty level of evidence suggested that RME seems to promote a variable reduction in frequency or a remission of NE in children in both the short (4, 6, and 8 months) and long term (13, 36, 48, and 120 months).

CONCLUSIONS

Based on currently available information, RME seems to promote an improvement in NE in children. However, the low quality of the existing evidence weakens the recommendation.

Analysis of nasal airway symmetry and upper airway changes after rapid maxillary expansion

INTRODUCTION

The objectives of this study were to assess the changes in right vs left nasal cavity volumes and minimum cross-sectional width, nasopharyngeal, and oropharyngeal volumes of the upper airway in response to rapid maxillary expansion (RME).

METHODS

Pretreatment and posttreatment cone-beam computed tomography scans of 28 patients with a mean age of 9.86 ± 2.43 years and 20 age- and sex-matched controls were digitized and linear, angular, and volumetric measurements were obtained.

RESULTS

Nasopharyngeal volume, right, and left nasal cavity volumes, and minimum cross-sectional widths increased significantly 2 years post RME (P <0.05). These measurements did not show any significant increase in the control group (P >0.05), whereas the oropharyngeal volume increase for both groups was comparable (P = 0.92). In the experimental group, the right and left nasal cavity volumes were not significantly different at baseline or posttreatment. However, the change that occurred was significantly larger for the left nasal cavity. This change for the control group was more significant for the right nasal cavity. Maxillary right and left molar inclinations were positively correlated to the nasal cavity volume, showing that the more buccally inclined the maxillary molars were, the smaller the nasal cavity volume.

CONCLUSIONS

Nasopharyngeal and right and left nasal cavity volumes and minimum cross-sectional widths increase significantly after RME in young children. Expansion decreases the degree of difference in volume between the right and left nasal cavities. The buccal inclination of maxillary molars is correlated with nasal cavity volume.

The effect of rapid maxillary expansion in children: a meta-analysis

INTRODUCTION

Craniofacial growth is modified by chronic mouth breathing. Rapid maxillary expansion leads to separation of the mid-palatal suture, improving the occlusion and the upper airway size.

AIM

Systematically evaluate scientific articles on the effects of rapid maxillary expansion on airway dimensions and classify the quality of the evidence of the information.

METHODS

Searches on PUBMED, LILACS, EMBASE, SCOPUS, WEB OF SCIENCE and COCHRANE, as well as in the grey literature were performed. The articles found were selected and evaluated both for the risk of bias (ROBINS-I) and for the quality of evidence (GRADE).

RESULTS

Of the 309 works found, 26 papers were selected for full reading, of which 22 were excluded. Data compilation and analysis were performed in four papers, two being controlled non-randomized clinical trials and two non-randomized and uncontrolled clinical trials. No randomized clinical trial was found.

CONCLUSIONS

The meta-analysis found an increase in the internasal and inter-zygomatic distances and oropharyngeal volume after rapid maxillary expansion, which, together with clinical findings, makes the recommendation favorable to the intervention. The quality of the evidence for each outcome was considered very low.

Short-term and long-term effects of rapid maxillary expansion on the nasal soft and hard tissue

OBJECTIVES

To evaluate nasal soft and hard tissue changes immediately post-rapid maxillary expansion (RME) and to assess the stability of these changes using cone beam computed tomography (CBCT).

MATERIALS AND METHODS

A total of 35 treatment group (TG) patients (18 girls, 17 boys; 9.39 ± 1.4) had a pre-RME CBCT and a post-RME CBCT approximately 66 days after expansion, and 25 patients had a follow-up CBCT 2.84 years later. A total of 28 control group (CG; no RME) patients (16 girls, 12 boys; 8.81 ± 1.6) had an initial CBCT and a CBCT an average of 2.25 years later. Soft and hard tissue nasal landmarks were measured in transverse, sagittal, and coronal planes of space on CBCT scans. Differences within the same group were evaluated by paired t-tests or Wilcoxon signed-rank tests. Long-term comparisons between TG and CG were evaluated by independent-sample t-tests or Wilcoxon rank-sum tests.

RESULTS

Immediately post-RME, there were statistically significant mean increases of 1.6 mm of alar base width, 1.77 mm of pyriform height, and 3.57 mm of pyriform width (P < .05). CG showed the significant increases over 2.25 years (P < .001). Compared with CG, the long-term evaluation of TG demonstrated only pyriform height and pyriform width showed a statistically significant difference (P < .01).

CONCLUSIONS

Although RME produced some significant increase on the nasal soft tissue immediately after expansion, it regressed to the mean of normal growth and development over time. However, long-term evaluation of TG compared with CG showed only pyriform height and pyriform width to be affected by RME.

Three-dimensional analyses of short- and long-term effects of rapid maxillary expansion on nasal cavity and upper airway: A systematic review and meta-analysis

INTRODUCTION

The purpose of this systematic review was to evaluate the three-dimensional (3D) changes occurring at short- and long-term follow-up after rapid maxillary expansion (RME) in nasal cavity (NC) and upper airway (UA) in growing patients.

METHODS

A literature search up to 1 July 2019 was performed. Randomized and non-randomized clinical trials and cohort studies comparing the effects of RME in a paediatric population using 3D analyses based on computed tomography (CT), cone-beam CT and MRI were included. The risks of bias of the included studies were assessed using the Cochrane Collaboration's risk of bias tool, the GRADE approach and a customized tool. The random-effects meta-analyses of the mean differences and 95% confidence intervals of NC and UA volume changes were carried out, followed by subgroup analyses.

RESULTS

Twenty-seven studies were included, with 18 selected for quantitative synthesis. Immediately after expansion, the nasopharynx and oropharynx increased significantly. After 3 months of retention, only the NC and nasopharynx showed a significant volume increase. Two studies mentioned the use of a sleep-disordered breathing questionnaire, and one study reported the difference before and after RME. None of the 27 articles included assessed the correlation between the skeletal widening and NC or UA volume changes after RME.

CONCLUSIONS

The existing evidence confirmed only the short-term positive effect of RME on expanding the volume of the NC and the upper part of the UA. However, long-term stability could not be sustained.

Parents’ Perceptions of Breathing Pattern Changes, Sleep Quality, and Fatigue in Children after Rapid Maxillary Expansion: A Survey and Case Series Study

Background:

Rapid Maxillary Expansion (RME) aims to re-establish balance between the widths of the jaws. It is mainly utilized to treat skeletal and dental manifestations associated with transverse maxillary constriction and to improve facial structures involving the nasal cavity.

Objectives:

This study aimed to investigate parents’ perceptions of breathing pattern changes after their child had undergone RME and the associated effects on sleep quality and fatigue. We also evaluated nasal cavity changes in three dimensions in six randomly selected patients.

Methods:

Ninety-one children aged 5-13 years with transverse maxillary deficiency and no major systemic diseases or syndromes were recruited. Their parents completed a 16-item questionnaire pre-treatment and 6 months post-treatment. The questionnaire included items pertaining to changes in (1) sleep apnea and breathing patterns, (2) sleep quality and fatigue, and (3) behavior. The cone beam computed tomography scans from six randomly chosen patients were also subjected to stereolithographic reconstruction of the midface pre-RME and post-RME.

Results:

Responses in the three domains exhibited good reliability. Significant improvements were observed in 59% of the items post vs. pre-RME. The overall rates of dry mouth in the morning, snoring half of the time, and heavy breathing decreased by ≥30%. The percentage change in headache in the morning, snoring loudly, and snoring half of the time was >80%. In addition, in the series of six cases, the mean difference in nasal cavity area post-RME was 4.1 mm2.

Conclusion:

Post-RME, parents perceived that their children exhibited improved behavior and were less fatigued during the day. Enhanced sleep quality and breathing patterns were also observed, but to a lesser extent.

Effects of non-surgical rapid maxillary expansion on nasal structures and breathing: A systematic review

OBJECTIVE

This systematic review aims to determine the effects of non-surgical rapid maxillary expansion (RME) on breathing and upper airway structures.

MATERIALS AND METHODS

An electronic search of the scientific literature from January 2005 to June 2016 was done using Web of Science, Dentistry & Oral Sciences Source and PubMed databases. A combination of search terms "rapid maxillary expansion", "nasal", "airway" and "breathing" were used. Studies that involved surgical or combined RME-surgical treatments and patients with craniofacial anomalies were excluded.

RESULTS

The initial screening yielded a total of 183 articles. After evaluation of the titles, abstracts and accessing the full text, a total of 20 articles fulfilled both inclusion/exclusion criteria and possessed adequate evidence to be incorporated into this review.

CONCLUSIONS

Non-surgical RME was found to improve breathing, increase nasal cavity geometry and decrease nasal airway resistance in children and adolescents.

Skeletal effects of RME in the transverse and vertical dimensions of the nasal cavity in mouth-breathing growing children

Introduction:

Maxillary constriction is a dentoskeletal deformity characterized by discrepancy in maxilla/mandible relationship in the transverse plane, which may be associated with respiratory dysfunction.

Objective:

The objective of this study was to evaluate the skeletal effects of RME on maxillary and nasal transverse dimensions and compare the differences between males and females.

Methods:

Sixty-one mouth-breathers patients with skeletal maxillary constriction (35 males and 26 females, mean age 9.6 years) were included in the study. Posteroanterior (PA) radiographs were taken before expansion (T1) and 3 months after expansion (T2). Data obtained from the evaluation of T1 and T2 cephalograms were tested for normality with the Kolmogorov-Smirnov method. The Student's t-test was performed for each measurement to determine sex differences.

Results:

RME produced a significant increase in all linear measurements of maxillary and nasal transverse dimensions.

Conclusions:

No significant differences were associated regarding sex. The RME produced significant width increases in the maxilla and nasal cavity, which are important for treatment stability, improving respiratory function and craniofacial development.

Impact of rapid maxillary expansion on nasomaxillary complex volume in mouth-breathers

Objective:

To assess the volumetric changes that occur in the nasomaxillary complex of mouth-breathing patients with transverse maxillary deficiency subjected to rapid maxillary expansion (RME).

Methods:

This was a controlled, prospective intervention study involving 38 mouth-breathing patients presenting with transverse maxillary deficiency, regardless of malocclusion type or race. Twenty-three of them comprised the experimental group, which was composed of 11 (47.8%) boys, and 12 (52.2%) girls, with a mean age of 9.6 years, ranging from 6.4 to 14.2 years and standard deviation of 2.3 years; and 15 of them comprised the control group, composed of 9 (60%) boys and 6 (40%) girls with an mean age of 10.5 years, ranging from 8.0 to 13.6 years, and standard deviation of 1.9 years. All patients were scanned (CT) according to a standard protocol: Initial CT (T₁), and CT three months thereafter (T₂), and the patients in the experimental group were treated with RME using a Hyrax expander for the correction of maxillary deficiency during the T₁-T₂ interval. The CT scans were manipulated using Dolphin^® Imaging version 11.7 software for total and partial volumetric assessment of the nasomaxillary complex.

Results:

The results revealed that in the experimental group there was a significant increase in the size of the structures of interest compared to the control group, both in general aspect and in specific regions.

Conclusions:

Rapid maxillary expansion (RME) provided a significant expansion in all the structures of the nasomaxillary complex (nasal cavity, oropharynx, right and left maxillary sinuses).

Effect of Rapid Maxillary Expansion on Glenoid Fossa and Condyle-Fossa Relationship in Growing Patients (MEGP): Study Protocol for a Controlled Clinical Trial

Aims and Objectives:

Rapid maxillary expansion (RME) is an orthodontic nonsurgical procedure aiming at increasing the width of the maxilla by opening mainly the intermaxillary suture in patients presenting a transverse maxillary skeletal deficiency. The objectives of the current prospective controlled clinical and radiographic study are to evaluate the hypothesis that RME in growing patients will result in radiographic changes at the level of interglenoid fossa distance, condyle-fossa relationship, and nasal cavity widths compared to the group who received no treatment initially and served as untreated control.

Materials and Methods:

In this prospective controlled clinical and radiographic study, forty healthy growing patients selected from a school-based population following a large screening campaign, ranging in age between 8 and 13 years, presenting a maxillary constriction with bilateral crossbite, and candidates for RME are being recruited. The first group will include participants willing to undergo treatment (n = 25) and the other group will include those inclined to postpone (n = 15).

Results:

The primary outcome is to compare radiologically the interglenoid fossa distance and the condyle-fossa relationship; nasal cavity width will be a secondary outcome. A multivariable analysis of Covariance model will be used, with the assessment of the time by group interaction, using age as covariate. The project protocol was reviewed and approved by the Ethics Committee of the Lebanese University, National Institute in Lebanon (CUEMB process number 31/04/2015). The study is funded by the Lebanese University and Centre National de Recherche Scientifique, Lebanon (Number: 652 on 14/04/2016).

Conclusion:

This prospective controlled clinical trial will give information about the effect of RME on the glenoid fossa and condyle-fossa relationship and its impact on the nasal cavity width.

Trial Registration:

Retrospectively registered in BioMed Central (DOI10.1186/ISRCTN77788053).

Salivary Markers and Microbial Flora in Mouth Breathing Late Adolescents

Objective

This is a 6-month observational case-control study that aims to estimate plaque index (PI), salivary flow, buffering capacity of saliva, and specific Streptococcus mutans (S. mutans) and Lactobacillus rates in a mouth breathing late adolescents sample, after a professional oral hygiene procedure and home oral hygiene instructions.

Subjects and Methods

A sample of 20 mouth breathing late adolescents/young adults (average: 19.2 ± 2.5; range: 18–23 years) and a matched control group of nose breathing subjects (average: 18.3 ± 3.2; range 18–23 years) were included in the study. All the participants were subjected to a professional oral hygiene procedure and appropriate home oral hygiene instructions (t0). After three months (t1) and six months (t2), the PI, salivary flow, buffering capacity of saliva, and S. mutans and Lactobacilli rates were recorded.

Results

The mean buffering capacity of saliva and the salivary flow rate showed no significant difference between the two groups, all over the observational period. For PI, a significantly higher mode (score 1 of PI) was observed in the study group at t1 (score 0 = 35% of subjects; score 1 = 60%; score 2 = 5%) and t2 (score 1 = 65% of subjects, score 2 = 35%), with respect to control group. Furthermore, mouth breathing subjects show a significant 4 times higher risk to develop S. mutans CFU > 10⁵ (CI lower limit: 0.95; CI upper limit: 9.48; chi-square: 4.28; p = 0.03), with respect to the control subjects.

Conclusions

Mouth breathing late adolescents show a significantly higher risk to develop S. mutans CFU > 10⁵ and an increased level of PI. Interceptive orthodontic treatments in growing subjects, like palatal expansion, are encouraged to improve the nasal air flow. In older subjects, orthodontic treatments should be performed with removable appliances like clear aligners, in order to allow a better oral hygiene level.

Digital evaluation of nasal changes induced by rapid maxillary expansion with different anchorage and appliance design

BACKGROUND

Scientific evidence showed that rapid maxillary expansion (RME) affects naso-maxillary complex, increasing nasal width and volume. This study aimed to evaluate nasal changes induced by rapid maxillary expansion with different anchorage and appliance design by using low dose and cone beam computed tomography.

METHODS

A total of 44 patients (20 males, mean age 8y 8 m ± 1y 2 m; 24 females mean age 8y 2 m ± 1y 4 m) were included in the investigation and divided into three groups according to the appliance: Hyrax-type expander anchored to permanent teeth, modified Hyrax-type expander anchored to deciduous teeth, modified Haas-type expander anchored to deciduous teeth. Maxillary expansion was performed until overcorrection and the expander was passively kept in situ for 7 months at least. All patients had three-dimensional imaging before expansion (T0) and after the retention period (T1). Nasal floor width, nasal wall width, maxillary inter-molar width were measured by means of Mimics software. The paired sample t-test was employed to assess the significance of the differences between the time points; the analysis of variance test (ANOVA) was used to compare differences between groups.

RESULTS

The statistical analysis revealed significant differences between T0 and T1 for each recorded measurement in each group; no significant differences were found by comparing groups.

CONCLUSIONS

Rapid maxillary expansion produces a significant skeletal transverse expansion of nasal region in growing patients. No significant differences in nasal effects are expected when the appliance is anchored onto deciduous teeth, with or without the palatal acrylic coverage.

Correlation between acoustic rhinometry, computed rhinomanometry and cone-beam computed tomography in mouth breathers with transverse maxillary deficiency

INTRODUCTION

To provide clinical information and diagnosis in mouth breathers with transverse maxillary deficiency with posterior crossbite, numerous exams can be performed; however, the correlation among these exams remains unclear.

OBJECTIVE

To evaluate the correlation between acoustic rhinometry, computed rhinomanometry, and cone-beam computed tomography in mouth breathers with transverse maxillary deficiency.

METHODS

A cross-sectional study was conducted in 30 mouth breathers with transverse maxillary deficiency (7-13 y.o.) patients with posterior crossbite. The examinations assessed: (i) acoustic rhinometry: nasal volumes (0-5cm and 2-5cm) and minimum cross-sectional areas 1 and 2 of nasal cavity; (ii) computed rhinomanometry: flow and average inspiratory and expiratory resistance; (iii) cone-beam computed tomography: coronal section on the head of inferior turbinate (Widths 1 and 2), middle turbinate (Widths 3 and 4) and maxilla levels (Width 5). Acoustic rhinometry and computed rhinomanometry were evaluated before and after administration of vasoconstrictor. Results were compared by Spearman's correlation and Mann-Whitney tests (α=0.05).

RESULTS

Positive correlations were observed between: (i) flow evaluated before administration of vasoconstrictor and Width 4 (Rho=0.380) and Width 5 (Rho=0.371); (ii) Width 2 and minimum cross-sectional areas 1 evaluated before administration of vasoconstrictor (Rho=0.380); (iii) flow evaluated before administration of vasoconstrictor and nasal volumes of 0-5cm (Rho=0.421), nasal volumes of 2-5cm (Rho=0.393) and minimum cross-sectional areas 1 (Rho=0.375); (iv) Width 4 and nasal volumes of 0-5cm evaluated before administration of vasoconstrictor (Rho=0.376), nasal volumes of 2-5cm evaluated before administration of vasoconstrictor (Rho=0.376), minimum cross-sectional areas 1 evaluated before administration of vasoconstrictor (Rho=0.410) and minimum cross-sectional areas 1 after administration of vasoconstrictor (Rho=0.426); (v) Width 5 and Width 1 (Rho=0.542), Width 2 (Rho=0.411), and Width 4 (Rho=0.429). Negative correlations were observed between: (i) Width 4 and average inspiratory resistance (Rho=-0.385); (ii) average inspiratory resistance evaluated before administration of vasoconstrictor and nasal volumes of 0-5cm (Rho=-0.382), and average expiratory resistance evaluated before administration of vasoconstrictor and minimum cross-sectional areas 1 (Rho=-0.362).

CONCLUSION

There were correlations between acoustic rhinometry, computed rhinomanometry, and cone-beam computed tomography in mouth breathers with transverse maxillary deficiency.