Evaluation of Three Types of Rapid Maxillary Expanders (Conventional, Hybrid, And MSE) on Maxilla in Adolescent A Randomized Clinical Trial - CBCT Study
Phase: NA
Conditions: Maxillary Retrusion, Nasal Airway Obstruction
Sponsor: Al-Azhar University

 
 
 
 
 
 
Evaluation of the Effect of Three Types of Rapid 
Maxillary Expanders (conventional, Hybrid and 
MSE)a randomized controlled trial  
  
NCT05446714 
Date : January 28, 2022 
 
 
 
 
 
 
 

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Evaluation of the Effect of Three Types of Rapid Maxillary 
Expanders (conventional, Hybrid and MSE)  
a randomized controlled trial  
CBCT Study 
Protocol submitted in partial fulfilment of the requirements for 
Academic Promotion Degree in Orthodontics 
By  
Mohamed Abd El-Rahman Shendy 
B.D.S (Al- Azhar University, Cairo, Boys) 2003G 
M.D.Sc (Al- Azhar University, Cairo, Boys) 2013G 
D.D.Sc (Al- Azhar University, Cairo, Boys) 2018G 
Lecturer, Department of Orthodontics 
Faculty of Dental Medicine 
Al- Azhar University 
Cairo (Boys) 
                                                                Contributors 
Dr. Mohamed Abd El-Rahman Shendy 
Lecturer, Department of Orthodontics 
Faculty of Dental Medicine, Boys, Cairo 
Al-Azhar University 
Dr Ahmed Mohamed Abouelnour 
Lecturer, Department of Orthodontics 
Faculty of Dental Medicine, Boys, Cairo 
Al-Azhar University 
Department of Orthodontics 
Faculty of Dental Medicine 
Al- Azhar University 
Cairo (Boys) 
 
 

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2022G – 1443H 
Introduction 
Rapid maxillary expansion (RME)is a common procedure for correcting 
posterior crossbite, mild maxillary crowding and maxillary arch constriction 
through opening the mid palatal suture. (1-3)   
RME can open the palatal and circum maxillary sutures, splitting of 
maxilla into two parts which affect nasal airway through increase nasal 
cavity volume followed by decreased nasal resistance and improved airflow 
especially in children with obstructive sleep apnea. (4-7) 
Previous studies reported that RME can improve the airway (8-10)  
On the other hand, other studies reported that RME does not affect 
oropharynx dimension. (11,12)  
 A systematic review mentioned that small changes in volume does not 
guaranty improvement in breathing mode, hence they advised the clinician 
not to do RME to improve the breathing mode. (13) 
Current evidence suggested that the conflict might be the different 
protocols of CBCT between studies, Head posture, tongue position, and 
segmentation protocols were not standardized in the selected studies hence 
they recommended more accurate and reliable protocol with fixed head and 
tongue positioning, also the segmentation method. (14) 
Other evidence showed improvement only limited to short term 
evaluation rather than long term one (15) While other evidence showed no 
improvement even with short term especially with miniscrew assisted rapid 
palatal expansion (MARPE). (16) 
So the aim of this study was to evaluate  the effect of three types of rapid 
maxillary expanders (conventional, Hybrid and MSE)  using cone beam 
computed tomography (CBCT) 

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Aim of study 
       The aim of this study was to compare the effect of three types of 
rapid maxillary expanders (conventional, Hybrid and MSE) using cone beam 
computed tomography (CBCT) 
 
The secondary outcomes 
a- Evaluation of periodontal condition of maxillary first permanent 
molars, both clinically and radiographically using CBCT 
b- Evaluation of Airway. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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Material and Methods  
Study design: 
Prospective randomized controlled trial 
 
Study setting and population: 
 
This study will be conducted on patients seeking orthodontic treatment 
in the outpatient clinic, Orthodontic department, Faculty of Dental Medicine, 
Al-Azhar University, Cairo, Boys branch.  
Eligibility criteria of population: 
 
The patients will be selected according to the following inclusions 
criteria: 
1- Patients suffering maxillary collapse with a skeletal background 
2- Patients with unilateral or bilateral posterior crossbite. 
3- Patients with reduced or average anterior face height. 
4- Patients with no periodontal disease. 
5- Patients with good oral hygiene and general health. 
6- No systemic diseases that may affect bone quality or interfere with 
orthodontic treatment. 
7- Patients with erupted maxillary permanent first molars and 
premolars.  
8- Patients with no previous orthodontic treatment. 
Sample size: 
     Sample size calculation using G power software was based on the 
observed effect sizes derived from previous article. (20) 

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  The calculation indicated that for a study with a power of 0.95 and an alpha 
of 0.05, a total of at least 45 patients (15 patients in each group) . 
Group allocation: 
     The patients will be classified and randomly allocated into three equal 
groups, using online generated randomization plan (Graph Pad) found at the 
website 
 http://www.graphpad.com/quickcalcs/index.cfm.:  
- Group (1): The conventional hyrax.  
-  Group (2): The Hybrid hyrax.   
- Group (3): The MSE expander. 
 
Interventions: 
       The current study was conducted on a total sample of forty five young 
adult orthodontic patients presented with transverse maxillary deficiency 
with an age ranged from 11-16 years. 
 
- All patients in this study will undergo a special protocol for oral 
hygiene measures for one month to standardize as possible the oral 
hygiene measure before expansion. 
- The following diagnostic records will be taken for each patient before 
and after the completion of expansion treatment: 
- Orthodontic study casts. 
- Standardized extra-oral and intra-oral photographs. 
- Panoramic and Upper occlusal radiographs. 
- Other radiographic evaluations that serve the purpose of the study 
according to the situation. 

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- Radiographic analysis will be performed for each patient to evaluate 
the effect of the rapid maxillary expansion on the nasal airway. 
 
Ethical consideration: 
        The objectives of the study will be discussed to the patients and parents 
and informed consent will be signed before treatment (form is attached). 
Data management and analysis: 
- The collected data will be statistically analyzed using SPSS. 
The Institutional Ethical Committee: approval number 775/220 
 
 
 
References 
 
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