Clinical Evaluation of Monolithic Zirconia FPDs

Study Overview
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Brief Summary
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The objectives of the present study are to compare the survival rates and possible biological and technical complications of metal-ceramic, veneered and monolithic zirconia posterior three-unit fixed partial dentures. The null hypothesis is that no differences would be found between the parameters studied for each type of restoration.

Detailed Description
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Ninety patients requiring at least one 3-unit Fixed partial denture (FPD) in the posterior region of the maxilla or mandible were included in this study. All subjects were recruited from the Master in Buccofacial Prostheses and Occlusion (Faculty of Odontology, University Complutense of Madrid, Spain). Before treatment, patients were informed of the study objectives, clinical procedures, materials used, advantages and possible risks of the ceramic material, and other therapeutic alternatives. Prior to the study, participants were asked to provide written informed consent. Ninety posterior FPDs were produced and allocated in parallel and randomly to either monolithic zirconia, veneered zirconia or MC restorations. The clinical procedures were performed by two experienced clinicians. All participants received oral hygiene instructions and a professional tooth cleaning prior to prosthetic treatment. The abutment teeth were prepared with a 0.8- to 1-mm-wide circumferential chamfer, an axial reduction of 1 mm and an occlusal reduction of 1.5- to 2.0-mm. A 10- to 15- degree angle of convergence was achieved for the axial walls. Tooth preparations were scanned with an intraoral scanner and the FPDs were designed using specific software. The restorations were then cemented using a resin self-adhesive cement. After cementation, occlusal contacts were evaluated, and the adjusted surfaces were polished using a porcelain polishing kit. The 90 FPDs were examined at 1week (baseline),1, 2 and 2 years by 2 researchers who were not involved in the restorative treatment.

Official Title
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Clinical Evaluation of Monolithic Zirconia and Metal-ceramic Posterior Fixed Partial Dentures

Conditions
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Dental Materials

Intervention / Treatment
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* Drug: Monolithic zirconia
* Other: Veneered zirconia
* Other: Metal-ceramic


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: One posterior tooth (molar or premolar) to be replaced Vital abutments or abutments with an adequate endodontic treatment Abutment not crowned previously Periodontally healthy abutments with no signs of bone resorption or periapical disease Adequate occlusogingival height for an appropiate connector area of at least 9 mm2 Stable occlusion and the presence of natural dentition in the antagonist arch. Exclusion Criteria: Patients who require a Fixed Dental Prosthesis of more than three units Patients who present reduced crown length (less than 3 mm occlusogingival heigth) Poor oral hygiene, high caries activity, or active periodontal disease

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 75 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: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Monolithic zirconia<br>Monolithic zirconia posterior 3-unit fixed partial dentures | Drug: Monolithic zirconia<br>* To assess the clinical performance and survival of posterior monolithic zirconia fixed partial dentures<br>* Other names: Zenostar T; Wieland Dental;|
| Active Comparator: Veneered zirconia<br>Veneered zirconia posterior 3-unit fixed partial dentures | Other: Veneered zirconia<br>* To assess the clinical performance and survival of posterior veneered zirconia fixed partial dentures<br>* Other names: IPS e.max ZirCAD;|
| Active Comparator: Metal-ceramic<br>Metal-ceramic posterior 3-unit fixed partial dentures | Other: Metal-ceramic<br>* To assess the clinical performance and survival of posterior metal-ceramic fixed partial dentures<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Quality of restorations at baseline | The quality of the surface and color, anatomical form and marginal integrity was assessed using the California Dental Association's assessment system. Each CDA criterion was ranked on a scale of 1 to 4, where 4 = excellent, 3 = good, 2 = unacceptable (repair), and 1 = unacceptable (replacement). | Baseline | 
| Quality of restorations at 1 year | The quality of the surface and color, anatomical form and marginal integrity was assessed using the California Dental Association's assessment system. Each CDA criterion was ranked on a scale of 1 to 4, where 4 = excellent, 3 = good, 2 = unacceptable (repair), and 1 = unacceptable (replacement). | 1 year | 
| Quality of restorations at 2 years | The quality of the surface and color, anatomical form and marginal integrity was assessed using the California Dental Association's assessment system. Each CDA criterion was ranked on a scale of 1 to 4, where 4 = excellent, 3 = good, 2 = unacceptable (repair), and 1 = unacceptable (replacement).ty was assessed | 2 years | 
| Quality of restorations at 3 years | The quality of the surface and color, anatomical form and marginal integrity was assessed using the California Dental Association's assessment system. Each CDA criterion was ranked on a scale of 1 to 4, where 4 = excellent, 3 = good, 2 = unacceptable (repair), and 1 = unacceptable (replacement). | 3 years | 
| Plaque Index (PI) at baseline | Plaque Index (PI) of the abutment and control teeth. A score of 0 to 3 was assigned. Higher score means a worse outcome. | Baseline | 
| Plaque Index (PI) at 1 year | Plaque Index (PI) of the abutment and control teeth. A score of 0 to 3 was assigned. Higher score means a worse outcome. | 1 year | 
| Plaque Index (PI) at 2 years | Plaque Index (PI) of the abutment and control teeth. A score of 0 to 3 was assigned. Higher score means a worse outcome. | 2 years | 
| Plaque Index (PI) at 3 years | Plaque Index (PI) of the abutment and control teeth. A score of 0 to 3 was assigned. Higher score means a worse outcome. | 3 years | 
| Gingival Index (GI) at baseline | Gingival Index (GI) of the abutment and control teeth. A score of 0 to 3 was assigned. Higher score means a worse outcome. | Baseline | 
| Gingival Index (GI) at 1 year | Gingival Index (GI) of the abutment and control teeth. A score of 0 to 3 was assigned. Higher score means a worse outcome. | 1 year | 
| Gingival Index (GI) at 2 years | Gingival Index (GI) of the abutment and control teeth. A score of 0 to 3 was assigned. Higher score means a worse outcome. | 2 years | 
| Gingival Index (GI) at 3 years | Gingival Index (GI) of the abutment and control teeth. A score of 0 to 3 was assigned. Higher score means a worse outcome. | 3 years | 
| Margin stability at baseline | To assess the gingival margin stability throughout the evaluation period (subgingival, isogingival or supragingival) | Baseline | 
| Margin stability at 1 year | To assess the gingival margin stability throughout the evaluation period (subgingival, isogingival or supragingival) | 1 year | 
| Margin stability at 2 years | To assess the gingival margin stability throughout the evaluation period (subgingival, isogingival or supragingival) | 2 years | 
| Margin stability at 3 years | To assess the gingival margin stability throughout the evaluation period (subgingival, isogingival or supragingival) | 3 years | 
| Probing depth at baseline | Probing depth of the abutment and control teeth. A score of 0 to 4 was assigned. Higher score means a worse outcome | Baseline | 
| Probing depth at 1 year | Probing depth of the abutment and control teeth. A score of 0 to 4 was assigned. Higher score means a worse outcome | 1 year | 
| Probing depth at 2 years | Probing depth of the abutment and control teeth. A score of 0 to 4 was assigned. Higher score means a worse outcome | 2 years | 
| Probing depth at 3 years | Probing depth of the abutment and control teeth. A score of 0 to 4 was assigned. Higher score means a worse outcome | 3 years | 
| Patient satisfaction at 3 years | Subjective patient satisfaction using Visual analogue scale (VAS) ranged from 0 (worst possible result) to10 (best possible result). The items analyzed were: esthetics, function, comfort, overall satisfaction | 3 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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fixed partial dentures, clinical evaluation, monolithic zirconia, veneered zirconia, survival