Angulated Screw-retained Crowns Following Immediate Implant Placement

Shanghai Jiao Tong University

Status and phase: Completed; Phase 3

Conditions: Tooth Diseases

Treatments: Procedure: Immediate implant placement; Procedure: Angulated screw-retained crowns placement; Procedure: Cemented crowns placement

Study type: Interventional

Funder types: Other

Identifiers

NCT04160247

SH9-19-07

Details and patient eligibility

About

There are two choices of restorations and implant abutments connection now: cemented and screw-retained.The excess cement, which would be difficult to completely remove, might lead to series of biological complications. The angulated screw channel (ASC) abutments, which recently introduced by Nobel Biocare , largely address the problem with visible screw access that may compromise esthetics. However, all of the present studies were clinical reports, thus the clinical efficacy of ASC abutments still needs the verification of evidence-based medicine with larger sample. Therefore, we designed a randomized controlled clinical trial study, aiming to verify the clinical efficacy of the ASC abutments by comparing screw-retained (with ASC abutments) single implant crowns with cemented ones in esthetic region.

Enrollment: 40 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

1. ≥18 years old and in good health;
2. Single tooth implant (type 1) in the esthetic region;
3. Patients with natural teeth adjacent to single implant crowns;
4. Patients with periodontal treatment before implant surgery;
5. The implants are from Nobel Biocare system with tapered link and the permanent restoration is a single crown and all-ceramic;
6. Soft tissue in the implanting-and-adjacent areas is healthy and free of infection

Exclusion criteria

1. Multiple implants in the esthetic region, or the restoration is a bridge
2. Patients with bone augmentation procedures;
3. Heavy smokers (>10 cigarettes/day);
4. Medically compromised patients (American Society of Anesthesiologists (ASA) classification III-IV);
5. Implants in an incorrect three-dimensional position (definition according to ITI VOL1);
6. Uncontrolled diabetes mellitus;
7. Unwilling to participate in the present study.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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40 participants in 2 patient groups, including a placebo group

Angulated screw-retained crown

Active Comparator group

Description:

Restorations are connected to the implants by angulated screw channel system

Treatment:

Procedure: Angulated screw-retained crowns placement

Procedure: Immediate implant placement

Cemented crown

Placebo Comparator group

Description:

Restorations are cemented onto the implant abutment

Treatment:

Procedure: Immediate implant placement

Procedure: Cemented crowns placement