Ceramic Tooth Restorations - a Comparison Study

Study Overview
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Brief Summary
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This randomized clinical study aims to compare success and survival of two different ceramic tooth restoration materials. The hypothesis for the study is that fluoride treated zirconia will retain as good as lithium disilicate reinforced glass ceramic when cemented by the same resin cement. One group of patients will receive a restoration in fluoride treated zirconia, the other group will receive a restoration in reinforced glass ceramic. All restorations will be cemented in the same manner. At 3, 6, 12 and 24 months the participants will be examined.

Detailed Description
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A randomized controlled clinical study that aims to compare success and survival of potassium hydrogen difluoride (KHF2) etched zirconium dioxide and lithium disilicate reinforced glass ceramic cemented to molars/premolares using dual cure resin cement. The null hypothesis for the study is that zirconium dioxide and lithium disilicate reinforced glass ceramic will retain equally good tooth substance when cemented with resin cement. Participants are recruited from the student clinic at Faculty of Dentistry, University of Oslo. Patients who fulfill the inclusion criteria 1) age above 18, 2) require restoration on premolar/molar and 3) are able to come to treatment and recall, are informed about the study and invited to participate. Consent to participation are signed by the patient. At any time and for any reason participants can withdraw from the study. Personal information will be registered in Service for Sensitive Data, which is a platform to collect, store, analyze and share sensitive data. An encoded research file will be kept separate from the patient journal.The content of this file will be patient journal number and classification of the restoration on a four level scale (Californian Dental Association - CDA) for each recall. A randomizing tool will be used to decide which ceramic restoration each participant will receive. Treatment will be performed by one clinician. The tooth preparation will be with little retention, and preferably supragingival. For cementing the restorations a standardized protocol for a dual cure resin cement will be used. Participants only have to pay for the dental technician expenses and will be the same amount regardless of type of ceramic. Each participant will be examined at 3, 6, 12 and 24 months by a clinician different from the one who performed the treatment. The 4 level CDA classification will be used to characterise each restoration. Each of the two treatment groups will consist of 20 participants. Significant results will be achieved with the approximate distribution across categories: Category 1: 19,9 %, category 2: 79,4 %, category 3: 4,6 %, category 4: 2,5 %

Official Title
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Success and Survival of e.Max and KHF2 Etched Zirconia Cemented With Resin Cement - a Randomized Controlled Clinical Study

Conditions
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Dental Restoration Failure of Marginal Integrity

Intervention / Treatment
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* Other: Ceramic tooth restoration


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18 years or older In the need of treatment on molars or premolars Lives near by Oslo - Exclusion Criteria: The patients that does not fulfill the inclusion criteria -

Ages Eligible for Study
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Minimum Age: 18 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: Randomized controlled clinical study
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Zirconia restorations<br>Dental restorations in surface modified zirconia bonded to tooth substance by dual cure resin cement | Other: Ceramic tooth restoration<br>* Dental restorations<br>|
| Active Comparator: e.max<br>Restorations in e.max bonded to tooth substance by dual cure resin cement | Other: Ceramic tooth restoration<br>* Dental restorations<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Survival | Restoration still retained to tooth | 2 years | 
| Loss of retention | Restoration not retained to tooth | 2 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| CDA-index: Romeo | Excellent: Surface smooth and glossy, no mismatch in color or shade | 2 years | 
| CDA-index: Sierra | Acceptable: SRO: Surface slightly rough or pitted, can be polished. SMM: slight mismatch in shade | 2 years | 
| CDA-index: Tango | Correct: TGI: surface glossy irregular, not subject to correction. TMM: mismatch between restoration and adjacent teeth outside normal range. | 2 years | 
| CDA-index: Victor | Replace: VSF: surface fractured. VGP: Gross porosities. VSD: shade in gross disharmony | 2 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Zirconium oxide, surface treatment, resin cement