Clinical Evaluation of Monolithic Zirconia Crowns

Universidad Complutense de Madrid

Status: Active, not recruiting

Conditions: Dental Materials

Treatments: Procedure: Metal-ceramic; Procedure: Monolithic zirconia

Study type: Interventional

Funder types: Other

Identifiers

NCT04943315

4157246 (Other Grant/Funding Number)

University Complutense Madrid

Details and patient eligibility

About

The objectives of the present study are to compare the survival rates and possible biological and technical complications of metal-ceramic, and monolithic third-generation zirconia posterior crowns. The null hypothesis is that no differences would be found between the parameters studied for each type of restoration.

Full description

Seventy patients requiring at least one crown 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. Seventy posterior crowns were produced and allocated in parallel and randomly to either monolithic third-generation zirconia, or metal-ceramic (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- 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 crowns 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 70 crowns were examined at 1week (baseline),1, 2 and 3 years by 2 researchers who were not involved in the restorative treatment.

Enrollment: 70 estimated patients

Sex: All

Ages: 20 to 75 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• One posterior tooth (molar or premolar) to be crowned
• Vital abutment or abutment with an adequate endodontic treatment
• Abutment not crowned previously
• Periodontally healthy abutment with no signs of bone resorption or periapical disease.
• Adequate occlusogingival height ≥ 4 mm.
• Stable occlusion and the presence of natural antagonist tooth.

Exclusion criteria

• Patients who present reduced crown length (less than 4 mm occlusogingival height).
• Poor oral hygiene, high caries activity, or active periodontal disease

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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70 participants in 2 patient groups

Monolithic zirconia

Experimental group

Description:

To assess the clinical performance and survival of posterior monolithic zirconia crowns

Treatment:

Procedure: Monolithic zirconia

Metal-ceramic

Active Comparator group

Description:

To assess the clinical performance and survival of posterior metal-ceramic crowns

Treatment:

Procedure: Metal-ceramic