Comparison of the Centric Relation Recorded by Two Methods Using Cone Beam Computed Tomography

Study Overview
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Brief Summary
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The purpose of this study was to investigate and compare the variation in mandibular relation recorded by the gothic arch methods and the K7 method using cone beam computed tomography (CBCT)

Detailed Description
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ten asymptomatic participants were selected,the centric relation registrations were separately recorded according to the technique of the gothic arch method and the neuromuscular method,subsequent, they were instructed to perform CBCT wearing two bite registrations,thus using dophin software to calculate the tmj space and the upper airway and using exocad software to ananyse the mandibular position, Data were analysed with paired t-test

Official Title
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Comparison of the Centric Relation Recorded by the Gothic Arch Methods and the Neuromuscular Method Using Cone Beam Computed Tomography

Conditions
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Tooth Loss

Intervention / Treatment
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* Procedure: the centric relation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: absence of the mandibular position Classified as ASA 1 or 2 (normal healthy patient or with mild systemic disease, according to the American Society of Anaesthesiologists Physical Status Classification System); Absence of the symptoms and signs of the temporomandibular joint; Willing to participate and to sign a written informed consent form. Exclusion Criteria: Cardiac pacemaker carriers and pregnant women; people with heart pace disorders and epilepsy; Temporomandibular or craniocervical disorders.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: record the centric relation using the gothic tracing method<br>the vertical dimension of occlusion (VDO) were were determineded through facial appearance observation,thus,the patients were trained to execute bordering protrusive, retrusive and bilateral lateral-protrusive movements wearing the intraoral apparatus and a Gothic Arch Tracing was made, the apex of the Gothic Arch Tracing was defined as the gothic arch position. | Procedure: the centric relation<br>* All participants were recorded the centric relation registrations according to the technique of the gothic tracing method and the neuromuscular method separately.<br>|
| Experimental: record the centric relation using the neuromuscular method<br>the participant were subjected to a low-frequency transcutaneous electrical nerve stimulation (TENS) using the J5 Myotronics for 45 minutes,With the help of TENS, complete relaxation of the muscles were achieved and the mandibular musculature was induced to guide the mandible in the physiologic position,thus using K7 to track the physical mandibular positon which was defined as the neuromuscular position. | Procedure: the centric relation<br>* All participants were recorded the centric relation registrations according to the technique of the gothic tracing method and the neuromuscular method separately.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the temporomandibular joint space | according to the method of Ikeda and Kawamura, tmj space measurement in sagittal of the CBCT images were performed | immediately | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the upper airway | Using the sinus/airway feature of the Dolphin software to reconstruct the upper airway,it included three region: the nasopharynx, oropharynx, and hypopharynx | immediately | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Cone-Beam computed tomography, the centric relation, the upper airway, mandibular position