Evaluation of Using Different Screwed Abutment Height

Evaluation of Straumann Bone Level Tapered® Implants Using Screwed Abutment Height in Partially Edentulous Patients: a Randomized Controlled Clinical Trial

A prospective randomized controlled clinical trial will be conducted. Study groups will be assigned as described above. The patients will be randomly divided into two groups in order to study the influence of prosthetic screw abutment in marginal bone loss (MBL) around Bone Level Tapered implants (BLT® Roxolid® SLActive® guided implants, Straumann Dental Implant System, Institut Straumann AG, Basel, Switzerland).

Study Overview

• Status: Completed
• Conditions: Bone Loss
• Intervention / Treatment: Device: Dental implant placement with COVER SCREW (two surgeries in control group) or DEFINITIVE TRANSEPITHELIAL ABUTMENT (one surgery in test group)

Detailed Description

48 patients will be selected with partial edentulism in the maxilla or mandible, requiring two dental implants in the posterior areas (molars and premolars).

Each patient will be randomly allocated in one of the two groups: test group (n=36) or control group (n=12) and all the implants will be placed by residents of the International Master in Oral Surgery and Master in Periodontics of the same University.

Study groups

Group 1: Two stage approach (cover screw in first surgery and healing abutment in second surgery) (12 patients)

Group 2: One stage approach (healing cap over trans-epithelial abutments) (36 patients).Two subgroups according to different trans-epithelial height abutment:

• Subgroup 2.1: Screw-retained abutment of 1 mm height (18 patients)
• Subgroup 2.2: Screw-retained abutment of 2.5 mm height (18 patients)

Clinical Parameters and Outcomes

• Three-dimensional volumetric changes in hard and soft tissues (Cone-beam computed tomography superposed with digital cast models).
• Marginal bone level (MBL) change: Standardized intraoral periapical x-rays will be taken on the day of surgery, 4, 6, 12, 24 and 36 months following surgery.
• Probing depth, bleeding on probing and keratinized mucosa width will be measured in the follow-up visits in 3 different points in buccal (Mesial, center and distal).
• VAS Scale: The visual analog scale or visual analog scale (VAS).

• Study Type: Interventional
• Enrollment (Actual): 30
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Spain
  • Barcelona, Spain, 08195
    • Universitat Internacional de Catalunya

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

1. Signed informed consent
2. Overall, healthy subjects
3. Females and males of at least eighteen-years
4. Requiring a minimum of two implants (molar and/or premolar teeth)
5. Adequate oral hygiene (less than 15% FMPS)
6. Able to follow instructions and attend a regular compliance
7. Enough bone to place a standard implant of 4.1 mm diameter.

Exclusion Criteria:

1. Acute local infection
2. Occlusal overload with parafunctional activity (assessed clinically)
3. Large occlusal discrepancies
4. Untreated periodontal disease assessed by Socransky et al. parameters (≥2mm clinical attachment loss in two consecutive visits within 1 year)
5. Smokers (more than 10 cigarettes/day)
6. Drug and/or alcoholic dependencies
7. Medical conditions contraindicating implant surgery
8. History of head and/or neck radiation
9. Bisphosphonate therapy

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Control group; Group 1: 2 stage approach (cover screw) (12 patients): cover screw is placed over the dental implants in the first surgery and a second surgery will be performed to expose the implants and placing a healing abutment after 2-4 months, DEVICES: COVER SCREW (first surgery) and HEALING ABUTMENT (second surgery)	Device: Dental implant placement with COVER SCREW (two surgeries in control group) or DEFINITIVE TRANSEPITHELIAL ABUTMENT (one surgery in test group); Dental implant placement using cover screws (first surgery) and a healing abutment (second surgery) or definitive transepithelial abutments the same day of the implant placement (one unit surgery)
Experimental: Test group; Group 2: Protective plastic cap over different definitive trans-epithelial abutments are placed in the unic surgery performed (36 patients): Definitive transepithelial abutments will be placed the same day of the implant placement surgery. DEVICE: DEFINITIVE TRANSEPITHELIAL ABUTMENT	Device: Dental implant placement with COVER SCREW (two surgeries in control group) or DEFINITIVE TRANSEPITHELIAL ABUTMENT (one surgery in test group); Dental implant placement using cover screws (first surgery) and a healing abutment (second surgery) or definitive transepithelial abutments the same day of the implant placement (one unit surgery)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Marginal Bone Loss	Periimplant bone level by measuring from the implant platform to the first bone to implant contact. Messuret in 2 points: MESIAL AND DISTAL with intra-oral XR. (measured in millimeters). The mean of this two-points for each implant was calculated. Afterwards, the mean for the mesial implants, distal and total implant sample per group was calculated.	After implant loading (baseline)and once every year to 24 months follow-up

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Probing Depth	Measuring this outcomes at 4 different points .(Mesial Buccal, Center Buccal, Distal Buccal and central lingual) (measured in millimeters).	After implant loading (baseline)and once every year to 36 months follow-up
Bleeding on Probing	Measuring this outcomes at 4 different points .(Mesial Buccal, Center Buccal, Distal Buccal and central lingual) (measured in millimeters).	After implant loading (baseline)and once every year to 36 months follow-up
Keratinized Mucosa Width	Measuring this outcomes at 4 different points .(Mesial Buccal, Center Buccal, Distal Buccal and central lingual) (measured in millimeters).	After implant loading (baseline)and once every year to 36 months follow-up

Collaborators and Investigators

• Sponsor: Universitat Internacional de Catalunya
• Investigators: Principal Investigator: Jordi Gargallo-Albiol, Universitat Internacional de Catalunya

Study record dates

Study Major Dates

• Study Start (Actual): July 1, 2017
• Primary Completion (Actual): July 30, 2022
• Study Completion (Actual): November 1, 2024

Study Registration Dates

• First Submitted: June 29, 2023
• First Submitted That Met QC Criteria: August 29, 2023
• First Posted (Actual): August 30, 2023

Study Record Updates

• Last Update Posted (Actual): June 26, 2025
• Last Update Submitted That Met QC Criteria: June 10, 2025
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Keywords: dental implant; bone loss; bone implant interface; Peri implant Endosseous Healing; Dental implant abutment
• Other Study ID Numbers: CIR-ECL-2016-03

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: The investigators will have all the informed consent forms, the clinical study report, the presurgical plan, the CBCT immediately post-surgery, and the outcome variable tables of each follow-up visit.
• IPD Sharing Time Frame: The first outcome will be available in July-2022 and the last outcome in July.2024
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; ICF; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No