Comparison of Masticatory Efficiency Between Complete Denture With Zero-degree Teeth and Anatomic Teeth in Patients With Severely Resorbed Ridge

Study Overview
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Brief Summary
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This study aims to evaluate masticatory efficiency of the zero-degree teeth complete denture in treatment of edentulous patients of severely resorbed ridge.Patients will be crossed over to be treated with zero-degree teeth complete denture and anatomic teeth complete denture. For each patient, the masticatory efficiency and electromyography with different denture will be recorded and analysis.

Official Title
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Comparison of Masticatory Efficiency and EMG Activity Between Complete Denture With Zero-degree Teeth and Anatomic Teeth in Patients With Severely Resorbed Ridge

Conditions
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Edentulous

Intervention / Treatment
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* Device: zero degree teeth
* Device: anatomic teeth


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: complete edentulism for at least three months class Ⅳ ridge Exclusion Criteria: neuromuscular dysfunction, psychiatric disorder,

Ages Eligible for Study
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Minimum Age: 50 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Zero-Degree Teeth, then Anatomic Teeth<br>edentulous patients who were first treated with zero-degree teeth complete denture, then with anatomic teeth complete denture | Device: zero degree teeth<br>* zero degree teeth complete denture was first prescribed to patients in group 1 while patients in group 2 were treated with anatomic teeth complete denture<br>Device: anatomic teeth<br>* when anatomic teeth complete denture was prescribed to patients in group 1, patients in group 2 were treated with zero degree teeth complete denture<br>|
| Experimental: Anatomic Teeth, then Zero-Degree Teeth<br>edentulous patients who were first treated with anatomic teeth complete denture, the with zero degree teeth complete denture | Device: zero degree teeth<br>* zero degree teeth complete denture was first prescribed to patients in group 1 while patients in group 2 were treated with anatomic teeth complete denture<br>Device: anatomic teeth<br>* when anatomic teeth complete denture was prescribed to patients in group 1, patients in group 2 were treated with zero degree teeth complete denture<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| EMG (Masseters EMG Are Recorded After Patient Wears Complete Denture for Three Months) | the masseters EMG are recorded after patient wears complete denture for three months,EMGs of masseters of 20 chewing strokes were recorded in term of value of amp and duration,amplitude is reported here as the average value from 20 chewing strokes in units of microvolts. | three months | 
| EMG (Masseters EMG Are Recorded After Patient Wears Complete Denture for Three Months) | the masseters EMG are recorded after patient wears complete denture for three months,EMGs of masseters of 20 chewing strokes were recorded in term of value of amp and duration, duration here is reporteds the average value from 20 chewing strokes in units of millisecond. | three month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Masticatory Efficiency Index | the masticatory efficiency is tested after patient wears complete denture for three months,each patient was given 4 gram dry peanuts, chewed for 20 seconds, then spat in the receptacle and rinsed mouth residue. The peanut particles were diluted to 1000 ml with distilled water, stirred for 1 minutes and standing for 2 minutes to suspension. Absorbance values(av) were measured at the wavelength of 590nm in a spectrophotometer. The higher the masticatory efficiency, the smaller the peanut particles, then the higher the av value, vice versa. Value of av was used to represent masticatory efficiency. For each patient, the test was conducted three times, and the average value of av was taken as the final result. A lower masticatory efficiency index indicates larger peanut particle size observed. | three months |