The Clinical Performance of Inlay Zirconia Bridges

Study Overview
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Brief Summary
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When missing tooth structure or teeth are replaced, minimal biologic risk should be involved to re-establish function and esthetics. The increased use of the adhesive technique and preservation of dental tissues have greatly impacted conservative tooth preparation design. The development use of zirconia technology and all-ceramic systems has opened the potential for fabrication inlays zirconia bridges with durability and good aesthetics. The purpose of this study is to clinically evaluate the placement of inlay bridge made of a Y-TZP framework veneered with a pressed ceramic and bonded with a completely adhesive approach in the replacement of a single missing tooth.

Detailed Description
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This study evaluates the use of inlay bridge made of Zirconia and all ceramic systems with three designs in the replacement process of one single tooth (i.e. a missing premolar or molar.) The first design is going to be fabricated with CAD/CAM Zirconia and the occlusal surface from e-max press. The second design is going to be fabricated with CAD/CAM Zirconia and the occlusal surface from e-max press and the internal surface coated with glaze layer to improve the adhesion. The third design is going to be fabricated with CAD/CAM Zirconia and the occlusal surface from e-max press and the internal surface coated with a layer of e-max ceramic press to improve the adhesion.

Official Title
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The Clinical Performance of Inlay Zirconia Bridges Using Three Different Designs

Conditions
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Dental Crowns

Intervention / Treatment
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* Procedure: Glaze layer
* Procedure: E-max Press layer


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Good oral hygiene Low susceptibility to caries Parallel alignment of abutment teeth Immobility of the abutment teeth Minimum height of abutment teeth ≥ 5 mm (connector thickness) Maximum mesio-distal extension of the inter-dental gap of 9 mm (width of premolar) or 12 mm (width of molar) Exclusion Criteria: Severe para-functional habits. Short clinical crowns (<5 mm) Extensive defects of the clinical crown, Loosening of teeth because of factors related to the periodontal tissues.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum 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: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Zirconia and E-max Press<br>The first design is going to be fabricated with CAD/CAM Zirconia and the occlusal surface from E-max Press. | |
| Experimental: Zirconia and E-max Press and Glaze<br>The second design is going to be fabricated with CAD/CAM Zirconia and the occlusal surface from E-max Press and the internal surface coated with a glaze layer to improve adhesion. | Procedure: Glaze layer<br>* A coating of a glaze layer will be used at the inner surface of the bridge to improve adhesion<br>|
| Experimental: Zirconia and E-max Press twice<br>The third design is going to be fabricated with CAD/CAM Zirconia and the occlusal surface from E-max Press and the internal surface coated with an E-max Press layer to improve adhesion. | Procedure: E-max Press layer<br>* A coating of E-max Press layer will be used at the inner surface of the bridge to improve adhesion<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in marginal fit | To examine if there is a gap between inlay margins and tooth cavity margins .It will be measured by a probe. | Immediately within five minutes following cementation (T1), 3 months (T2), 6 months (T3), 12 months (T4) following application | 
| Change in Material Integrity | To examine macroscopically the presence of cracks or fractures in the veneering ceramic (retainers or pontics) or any fractures at the connectors. | Immediately within five minutes following cementation (T1), 3 months (T2), 6 months (T3), 12 months (T4) following application | 
| Change in the Retention Status | The resistance of a prosthesis to displacement will be measured. | Immediately within five minutes following cementation (T1), 3 months (T2), 6 months (T3), 12 months (T4) following application | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Marginal Color Matching | Examination will be done macroscopically to detect the presence of any difference in color between the margins of the tooth and inlays | Immediately within five minutes following cementation (T1), 3 months (T2), 6 months (T3), 12 months (T4) following application |