Functional Relining Versus Digital Altered Cast Using Digitally Fabricated Distal Extension Frameworks

Study Overview
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Brief Summary
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This clinical study will be done to compare between functional relining and digital altered cast of selective pressure impression techniques for constructing mandibular distal extension removable partial dentures using digitally fabricated frameworks by measuring the abutment alveolar bone height changes.

Detailed Description
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According to the functional impression techniques, all patients will be classified into two equal groups: Group A: Functional relining of processed RPD base at insertion: •After try in, a record base will be attached to the minor connectors and metal frameworks using 3D printed master cast.The finished removable partial denture is relined using the functional relining impression technique. Group B : Digitally obtained altered cast : Selective pressure impression technique will be made. Digital altered cast will be done according to J. Wu, Y. Cheng (20) as follow : All patients will be informed about the follow up and evaluation recalls. Evaluation of abutment alveolar bone height changes: Alveolar bone height changes of abutment teeth will be evaluated radiographically at insertion (T0), and after 6 (T6) & 12 months (T12) after RPD insertion.

Official Title
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Functional Relining Versus Digital Altered Cast Of Selective Pressure Impression Techniques Using Digitally Fabricated Distal Extension Frameworks: Abutment Alveolar Bone Height Changes

Conditions
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Dental Prosthesis Complication

Intervention / Treatment
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* Procedure: Removable partial denture


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 1. All patients having completely edentulous maxilla opposing class I Kennedy mandible. 2. Sufficient restorative space must be available (from the mucosa covering the crest of the residual ridge to proposed occlusal plane). This will be detected by a tentative jaw relation. 3. Well formed residual ridge covered by healthy firm mucosa. 4. All patients are of angel's class I maxillo-mandibular relationships. 5. Abutment teeth must fulfil certain criteria: Abutment teeth should be healthy with good periodontal and bone support. Should not show a pronounced degree of mobility or advanced gingival recession. Crown Root Ratio of abutment teeth not more than 1:2 Exclusion Criteria: 1. Sever soft tissue undercuts. 2. Systemic diseases that may affect bone changes such as diabetes and osteoporosis. 3. History of radiotherapy in the head and neck region.

Ages Eligible for Study
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Minimum Age: 40 Years
Maximum Age: 70 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: Parallel Assignment
Interventional Model Description: h. According to the functional impression techniques, all patients will be classified into two equal groups: Group A: Functional relining of processed RPD base at insertion Group B : Digitally obtained altered cast
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: • Group 1 (Functional relining of processed RPD base at insertion)<br>After try in, a record base will be attached to the minor connectors and metal frameworks using 3D printed master cast. Registration of jaw relation. Mounting of master casts on articulator. Setting of artificial teeth according to lingualized occlusion principles. Try in of RPD. Flasking of RPD to obtain mandibular distal extension removable partial dentures. The finished removable partial denture is relined using the functional relining impression technique. | Procedure: Removable partial denture<br>* All patients will receive Removable partial denture by two different impression techniques<br>|
| Active Comparator: • Group 2 (Digitally obtained altered cast );<br>Construction of custom tray on metal frame work. Border molding of custom tray. Selective pressure impression technique will be made. Digital altered cast will be done according to J. Wu, Y. Cheng 3D printing of altered master cast that will be used for completing the construction of RPD with the same steps of group (A) but without relining. Finally the occlusion of dentures in the two groups will be verified before delivery. | Procedure: Removable partial denture<br>* All patients will receive Removable partial denture by two different impression techniques<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| abutment alveolar bone loss | Alveolar b(one height changes of abutment teeth will be evaluated radiographically at insertion and after one year | Two year |