Peri-implant Tissues Changes for Different Abutment Shapes and Heights

Influence of Supracrestal Soft Tissue on Peri-implant Bone Changes for Different Abutment Shapes and Heights: A Four-Arm Randomized Clinical Trial

The goal of this randomized clinical trial is to investigate the influence of supracrestal soft tissue on abutments of different heights (2-mm vs. 3-mm) and shapes (cylindrical abutment vs. concave abutment) on changes in the marginal bone level (bone loss and bone remodeling) in healthy, partially edentulous volunteer patients undergoing implant-supported rehabilitation.

The main questions it aims to answer are:

• Is there any difference in marginal bone loss for different abutment shapes and heights?
• Do the shape and height of the abutment affect implant success?

All participants will receive bone-level dental implants placed approximately 2-mm below the bone crest, each receiving a different type of abutment and researchers will see whether the shape and height of the abutment influence the success of the implant, periodontal probing depth (PPD), and bleeding on probing (BoP) comparing four groups of patients:

1. 2-mm high abutments with cylindrical shape.
2. 2-mm high abutments with concave shape.
3. 3-mm high abutments with cylindrical shape.
4. 3-mm high abutments with concave shape.

Clinical and radiographic assessments will be performed at abutment placement, at definitive prosthesis placement, and at 1, 3, 6, and 12 months after loading to measure marginal bone loss and peri-implant parameters.

Study Overview

• Status: Not yet recruiting
• Conditions: Dental Implant-Abutment Designs; Soft Tissue Management in Subcrestal Dental Implants; Marginal Bone Loss in Different Abutment Designs
• Intervention / Treatment: Procedure: Bone-Level Implant Placement with Transmucosal Abutment and One Abutment-One Time Protocol

• Study Type: Interventional
• Enrollment (Estimated): 180
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Juan C Bernabeu Mira, DDS, MSc, PhD; Phone Number: +34 697348312; Email: juan.c.bernabeu@uv.es

Study Locations

• Spain
  • Valencia
    • Valencia, Valencia, Spain, 46010
      • Universitat de València
      • Contact: Juan C Bernabeu Mira, DDS, MSc, PhD; Phone Number: +34 697348312; Email: juan.c.bernabeu@uv.es
      • Contact: David Peñarrocha Oltra, DDS, MSc, PhD; Email: david.penarrocha@uv.es

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Adults aged 18 years or older.
• Posterior edentulism (premolars/molars).
• Good general and oral health, with controlled plaque and bleeding indices.
• Sufficient bone height and width for implant placement without the need for bone regeneration procedures. Patients who require indirect sinus lift procedure simultaneously with implant placement may be included in the study.
• Presence of at least 2 mm of keratinized mucosa around the dental implant.
• Stable occlusion and healthy periodontium.
• Insertion torque ≥ 35 Ncm at the time of implant placement.
• Willingness to comply with study protocol and attend scheduled follow-up visits.

Exclusion Criteria:

• Presence of medical conditions that contraindicate implant surgery, such as heavy smoking (>10 cigarettes per day), severe bruxism, pregnancy or breastfeeding, bisphosphonate therapy, and patients undergoing chemotherapy or radiotherapy in the head and/or neck area.
• Active periodontal disease or peri-implant infection.
• Uncooperative patients or patients unable to complete follow- up.
• Implant failures.

Study Plan

How is the study designed?

Design Details

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

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: 2-mm high abutment with cylindrical shape; Participants in this group will receive a 2-mm high abutment with cylindrical shape placed immediately after implant surgery. The abutment will remain in place throughout the healing period, following a one abutment-one time protocol.	Procedure: Bone-Level Implant Placement with Transmucosal Abutment and One Abutment-One Time Protocol; Participants will receive bone-level dental implants placed approximately 2 mm below the bone crest in a healed posterior site of the maxilla or mandible. The implants will be placed using biological drilling protocol and inserted with a final torque of at least 35 Ncm following the manufacturer's instructions . A transmucosal abutment according to the applicable randomization will be connected at the time of surgery with a final torque of at least 30 Ncm, following the "one abutment-one time" philosophy in order to avoid any changes in hard and soft peri-implant tissues.
Experimental: 2-mm high abutment with concave shape; Participants in this group will receive a 2-mm high abutment with concave shape placed immediately after implant surgery. The abutment will remain in place throughout the healing period, following a one abutment-one time protocol.	Procedure: Bone-Level Implant Placement with Transmucosal Abutment and One Abutment-One Time Protocol; Participants will receive bone-level dental implants placed approximately 2 mm below the bone crest in a healed posterior site of the maxilla or mandible. The implants will be placed using biological drilling protocol and inserted with a final torque of at least 35 Ncm following the manufacturer's instructions . A transmucosal abutment according to the applicable randomization will be connected at the time of surgery with a final torque of at least 30 Ncm, following the "one abutment-one time" philosophy in order to avoid any changes in hard and soft peri-implant tissues.
Experimental: 3-mm high abutment with cylindrical shape; Participants in this group will receive a 3-mm high abutment with cylindrical shape placed immediately after implant surgery. The abutment will remain in place throughout the healing period, following a one abutment-one time protocol.	Procedure: Bone-Level Implant Placement with Transmucosal Abutment and One Abutment-One Time Protocol; Participants will receive bone-level dental implants placed approximately 2 mm below the bone crest in a healed posterior site of the maxilla or mandible. The implants will be placed using biological drilling protocol and inserted with a final torque of at least 35 Ncm following the manufacturer's instructions . A transmucosal abutment according to the applicable randomization will be connected at the time of surgery with a final torque of at least 30 Ncm, following the "one abutment-one time" philosophy in order to avoid any changes in hard and soft peri-implant tissues.
Experimental: 3-mm high abutment with concave shape; Participants in this group will receive a 3-mm high abutment with concave shape placed immediately after implant surgery. The abutment will remain in place throughout the healing period, following a one abutment-one time protocol.	Procedure: Bone-Level Implant Placement with Transmucosal Abutment and One Abutment-One Time Protocol; Participants will receive bone-level dental implants placed approximately 2 mm below the bone crest in a healed posterior site of the maxilla or mandible. The implants will be placed using biological drilling protocol and inserted with a final torque of at least 35 Ncm following the manufacturer's instructions . A transmucosal abutment according to the applicable randomization will be connected at the time of surgery with a final torque of at least 30 Ncm, following the "one abutment-one time" philosophy in order to avoid any changes in hard and soft peri-implant tissues.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes in peri-implant marginal bone level (mm)	Parallelized periapical radiographs will be obtained and a calibrated digital tool will be used to determine the vertical distance from the implant-abutment junction to the most coronal bone-to-implant contact on the mesial and distal sides. Unit of measure: Milimeters (mm)	From abutment placement (baseline time [TB]), 3 months post-op (prosthetic loading) (T0), and at months 1 (T1), 3 (T3), 6 (T6), and 12 (T12) after definitive prosthesis placement.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Peri-implant probing depth (mm)	Peri-implant soft tissue condition will be assessed by recording PPD using a periodontal probe at six surfaces per implant (mesiobuccal, midbuccal, distobuccal, and the corresponding lingual/palatal sites) to calculate the mean of every implant. Unit of measure: Milimeters (mm)	3 months post-op (prosthetic loading) (T0), and at months 1 (T1), 3 (T3), 6 (T6), and 12 (T12) after definitive prosthesis placement.
Bleeding on probing (presence/absence)	Bleeding on probing will be measured by gently passing a periodontal probe (using ~20-25g of force) to the base of the sulcus/pocket of the prosthesis at six surfaces per implant (mesiobuccal, midbuccal, distobuccal, and the corresponding lingual/palatal sites), then waiting 30 seconds to observe bleeding. It will be recorded as a dichotomous score (yes/no). Unit of measure: Percentage of sites showing bleeding per implant.	3 months post-op (prosthetic loading) (T0), and at months 1 (T1), 3 (T3), 6 (T6), and 12 (T12) after definitive prosthesis placement.
Implant success	Assessment of the implants will follow the criteria outlined by Misch et al. (2008) categorizing them into success (optimal health), satisfactory survival, compromised survival, or failure.	From the time of surgery through the end of the 12-month follow-up period after definitive prosthesis placement.

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
General variables	Patient age and sex, smoking habit (no smoking or ≤10 cigarettes/day), brushing habit (0, 1-2 or 3 times/day), edentulism (interdental or free end), phenotype (thin or thick), antagonist (natural teeth, bridge on teeth, implant rehabilitation or removable rehabilitation), cause of dental loss (caries, periodontitis or fracture), arch, quadrant, and soft tissue thickness (in mm) will be collected.	At enrollment time.

Collaborators and Investigators

• Sponsor: University of Valencia
• Investigators: Principal Investigator: María I Suárez Antoima, DDS, MSc, Universitat de València

Study record dates

Study Major Dates

• Study Start (Estimated): June 1, 2026
• Primary Completion (Estimated): July 31, 2027
• Study Completion (Estimated): September 30, 2027

Study Registration Dates

• First Submitted: March 24, 2026
• First Submitted That Met QC Criteria: March 28, 2026
• First Posted (Actual): April 3, 2026

Study Record Updates

• Last Update Posted (Actual): April 3, 2026
• Last Update Submitted That Met QC Criteria: March 28, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: dental implant; marginal bone loss; implant abutment; prostheses abutment width; prostheses abutment height
• Other Study ID Numbers: UV-INV-ETICA-3792382

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: The plan to share individual participant data (IPD) has not yet been determined.

Drug and device information, study documents

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