Gingival Response and Marginal Adaptation of Zirconia Crowns With Two Subgingival Margin Designs

Study Overview
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Brief Summary
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The aim of the study is to evaluate the effect of feather edge finish line and deep chamfer finish line on gingival position, bleeding on probing and marginal adaptation.

Detailed Description
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The aim of the study is to evaluate the effect of feather edge finish line and deep chamfer finish line on gingival position, bleeding on probing and marginal adaptation. Gingival bleeding on probing will be evaluated before treatment. Preparation for all ceramic full coverage restoration will be performed according to manufacturer instructions by one operator. Type of finish line (whether feather edge or deep chamfer finish line) will be selected randomly according to a computer generated randomization list. Restorative margins will be placed subgingivally. Zirconia crowns will be fabricated for the prepared teeth and cemented using resin luting agent. At 6 months and 12 months after the cementation, restorative margin position relative to the gingival margin will be recorded. Bleeding on probing and marginal adaptation will also be recorded.

Official Title
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Gingival Response and Marginal Adaptation of Zirconia Crowns With Two Subgingival Margin Designs: A Randomized Clinical Trial

Conditions
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Gingival Recession, Localized

Intervention / Treatment
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* Procedure: Feather edge finish line preparation
* Procedure: Deep chamfer finish line preparation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients 18 years to 50 years old Dentate patients planned for a single full coverage restoration in the posterior area. Patients with no active periodontal disease. >2mm of keratinized tissue Exclusion Criteria: Smoking (>10 cigarettes a day) Substance abuse history Patients with poor oral hygiene and high caries index Patients suffering from abnormal occlusal habits for example clenching or bruxism Local or systemic disease (endocrine, renal, hematologic, hepatic, immunosuppressive) Current steroid/chemotherapy Head and neck irradiation Pregnancy Inability or unwillingness to return for follow up visits.

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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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
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Tested finish line preparation<br>Feather edge finish line preparation (Intervention) | Procedure: Feather edge finish line preparation<br>* Tooth preparation with feather edge finish line will be done to posterior teeth to receive all ceramic full coverage zirconia crowns.<br>|
| Active Comparator: Comparator finish line preparation<br>Deep chamfer finish line preparation (Comparator) | Procedure: Deep chamfer finish line preparation<br>* Tooth preparation with deep chamfer finish line will be done to posterior teeth to receive all ceramic full coverage zirconia crowns.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Position of the margin of the restoration in relation to the gingival margin position | Scoring proposed by Paniz et al classified into either subgingival (not visible), equigingival (slightly visible) and supragingival (visible) | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Bleeding on probing | Scoring following Ainamo and Bay gingival bleeding index | 1 year |