Clinical trial NCT04943315: Clinical Evaluation of Monolithic Zirconia Crowns
Official title: Clinical Evaluation of Monolithic Zirconia and Metal-ceramic Posterior Crowns
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Dental Materials
Keywords: crowns
metal-ceramic
monolithic zirconia
clinical evaluation
survival
wear
Lead sponsor: Universidad Complutense de Madrid
Sponsor class: OTHER
Collaborators: name: Kuraray Co. Ltd
First posted: 2021-06-29
Enrollment: 70
Sex: ALL
Minimum age (years): 20
Maximum age (years): 75
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: 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.

Detailed 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.

Eligibility criteria: 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

Primary outcomes:
measure: Quality of restorations at baseline
timeFrame: Baseline
measure: Quality of restorations at 1 year
timeFrame: 1 year
measure: Quality of restorations at 2 years
timeFrame: 2 years
measure: Quality of restorations at 3 years
timeFrame: 3 years
measure: Plaque Index (PI) at baseline
timeFrame: baseline
measure: Plaque Index (PI) at 1 year
timeFrame: 1 year
measure: Plaque Index (PI) at 2 years
timeFrame: 2 years
measure: Plaque Index (PI) at 3 years
timeFrame: 3 years
measure: Gingival Index (GI) at baseline
timeFrame: Baseline
measure: Gingival Index (GI) at 1 year
timeFrame: 1 year
measure: Gingival Index (GI) at 2 years
timeFrame: 2 years
measure: Gingival Index (GI) at 3 years
timeFrame: 3 years
measure: Margin stability at baseline
timeFrame: Baseline
measure: Margin stability at 1 year
timeFrame: 1 year
measure: Margin stability at 2 years
timeFrame: 2 years
measure: Margin stability at 3 years
timeFrame: 3 years
measure: Probing depth at baseline
timeFrame: Baseline
measure: Probing depth at 1 year
timeFrame: 1 year
measure: Probing depth at 2 years
timeFrame: 2 years
measure: Probing depth at 3 years
timeFrame: 3 years
measure: Patient satisfaction at 3 years
timeFrame: 3 years
Secondary outcomes:
Other outcomes:
Locations:
city: Madrid
country: Spain
facility: Faculty of Odontology
Study officials:
affiliation: Universidad Complutense de Madrid
name: Maria J Suarez, PhD
role: STUDY_DIRECTOR
References: