To Compare Cemented Versus Screw-retained Implant-supported Single Crowns With Customized Zirconia Abutments

A Randomized Controlled Clinical Trial Comparing Cemented Versus Screw-retained Implant-supported Single Crowns With Customized Zirconia Abutments

The aim of this study is to test whether or not the use of screw-retained implant crowns on customized zirconia abutments results in biological, technical and esthetic outcomes similar to those obtained with cemented all-ceramic crowns on customized zirconia abutments, both made with a computer-aided design and manufacturing procedure (CAD/CAM).

The null-hypotheses is that marginal bone level change is equal at screw-retained and cemented crowns

Study Overview

• Status: Completed
• Conditions: Implant-supported Single Crowns
• Intervention / Treatment: Procedure: Cemented crowns; Procedure: Screw-retained crowns

• Study Type: Interventional
• Enrollment (Actual): 34
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Switzerland
  • Zurich, Switzerland, 8032
    • Clinic of Reconstructive Dentistry

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Single-tooth Straumann Bone Level in the anterior maxilla or mandible
• At least one adjacent natural tooth present
• Implant position enabling both screw-retained and cemented crown
• Informed consent signed

Exclusion Criteria:

• Smoking more than 15 cigarettes a day
• Poor oral hygiene (Plaque index over 30%)
• Pregnancy at the date of inclusion

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Cemented single crowns; Cemented single crown: zirconia abutment (Straumann Cares abutment) with an all-ceramic lithium disilicate crown	Procedure: Cemented crowns; The final lithium disilicate crowns will be cemented with an adhesive cement after tightening the abutments with the torque indicated by the manufacturer and closing the screw access hole with white guttapercha. The abutment will be cleaned with ethanol. A retraction cord will be placed for cementation if indicated. The crown will be etched with hydrofluoric acid and subsequently silanized. A sufficient amount of cement will be filled in the crown without creating major excesses. When the crown is seated correctly, the cement will be light-cured for a few seconds to facilitate the removal of the now hard excess cement. - Excess cement will be meticulously removed with a carbon scaler. The removal of all excess cement will be checked with an X-ray and by visual and tactile inspection.
Active Comparator: Screw-retained single crown; Screw-retained single crown: zirconia abutment (Straumann Cares abutment), directly veneered with veneering ceramic	Procedure: Screw-retained crowns; The screw-retained crowns will be inserted and tightened with the torque indicated by the manufacturer. The screw access hole will to be closed with white guttapercha and a composite filling (Filtek, 3M ESPE).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Marginal bone level	The bone level represents an indicator of the osseointegration and biological success of the implant.	5 years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Biological, technical and esthetic outcome	Radiographic bone level after 1 and 3 years	up to 5 years
Biological, technical and esthetic outcome	implant survival after 1, 3 and 5 years	up to 5 years
Biological, technical and esthetic outcome	rate of biological complications after 1, 3 and 5 years	up to 5 years
Biological, technical and esthetic outcome	rate of technical complications after 1, 3 and 5 years	up to 5 years

Collaborators and Investigators

• Sponsor: University of Zurich

Study record dates

Study Major Dates

• Study Start (Actual): July 27, 2012
• Primary Completion (Actual): November 11, 2019
• Study Completion (Actual): November 11, 2019

Study Registration Dates

• First Submitted: July 9, 2012
• First Submitted That Met QC Criteria: July 16, 2012
• First Posted (Estimate): July 19, 2012

Study Record Updates

• Last Update Posted (Actual): November 6, 2020
• Last Update Submitted That Met QC Criteria: November 4, 2020
• Last Verified: November 1, 2020

More Information

Terms related to this study

• Other Study ID Numbers: 2012-0147