Evaluation of Marginal Bone Loss (MBL) 12 Months Post-loading of Implants Supporting Individual Crowns, Based on the Height of the Intermediate Abutment and Its Placement Time. Immediate Abutments of 2 or 3 Mm Show the Lowest MBL, Whereas 1.5 Mm or Delayed Abutments Are Associated with Higher MBL.

NCT06667531 | Completed

• 1 other identifier: C.I. PI22/324
• Study Type: interventional
• Target: 54
• Locations: 1 country
• Sites: 1

Brief Summary

Objectives:To determine which combination of abutment height and timing of placement is most effective in reducing marginal bone loss (MBL). Materials and Methods: 54 patients received at least one single screw-retained crown on an implant replacing a posterior tooth (60 implants). The implants were divided into six treatment groups based on the height (1.5 mm; 2 mm; 3 mm) and timing of placement (immediate: surgery 1; delayed: surgery 2) of the intermediate abutment: group 1 (height 3; surgery1), group 2 (height 2; surgery1), group 3 (height 1.5; surgery1), group 4 (height 3; surgery2), group 5 (height 2; surgery2), group 6 (height 1.5; surgery2). Mesial and distal linear radiographic measurements (from the implant shoulder to the bone crest) were performed at five follow-up times: implant surgery, crown placement (T1), and at 3 (T2), 6 (T3), and 12 months after loading (T4). Partial and total MBL were compared among the treatment groups.

Conditions

Marginal Bone Loss

Keywords

marginal bone loss; abutment height; abutment placement timing

Outcome Measures

Primary Outcomes (1)

• Marginal bone loss (MBL) measured in mm (mm) 12 months after loading the implant.

  Cumulative MBL after 12 months of prosthetic loading measured in millimeters.

  12 months

Secondary Outcomes (1)

• Evolution over time of marginal bone loss (MBL) measured in millimeters (mm) at different stages.

  0, 3, 6, 12 months.

Study Arms (6)

Group 1 (height 3; surgery 1)

ACTIVE COMPARATOR

Placement of an immediate intermediate abutment (in implant placement surgery). This abutment has a height of 3 mm.

Procedure: Implant

Group 2 (height 2; surgery 1)

ACTIVE COMPARATOR

Placement of an immediate intermediate abutment (in implant placement surgery). This abutment has a height of 2 mm.

Procedure: Implant

Group 3 (height 1.5; surgery 1)

ACTIVE COMPARATOR

Placement of an immediate intermediate abutment (in implant placement surgery). This abutment has a height of 1.5 mm.

Procedure: Implant

Group 4 (height 3; surgery 2)

ACTIVE COMPARATOR

Placement of a delayed intermediate abutment (in the second implant surgery). This abutment has a height of 3 mm.

Procedure: Implant

Group 5 (height 2; surgery 2)

ACTIVE COMPARATOR

Placement of a delayed intermediate abutment (in the second implant surgery). This abutment has a height of 2 mm.

Procedure: Implant

Group 6 (height 1.5; surgery 2)

ACTIVE COMPARATOR

Placement of a delayed intermediate abutment (in the second implant surgery). This abutment has a height of 1.5 mm.

Procedure: Implant

Interventions

Implant PROCEDURE

Placement of an immediate intermediate abutment (in implant placement surgery). This abutment has a height of 3 mm.

Also known as: Oral Surgery

Group 1 (height 3; surgery 1)

Eligibility Criteria

• Age: 21 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Healthy adults.
• Plaque and bleeding indices below 10%.
• Absence of chronic periodontal diseases (periodontitis) or acute periodontal diseases (periodontal abscess).
• Presence of intact alveolar walls.
• Sufficient bone height and width.
• Need for restoration of a tooth in the posterior maxillary or mandibular region (premolars and molars).
• Incorporation into a periodontal maintenance program.

You may not qualify if:

• History of systemic disease or radiotherapy contraindicating bone surgery.
• Pregnant or breastfeeding women.
• Smokers of more than 10 cigarettes per day.
• Parafunctional habits.
• Alcohol or drug abuse.
• Narrow interproximal spaces (less than 9 mm).
• Placement of implants flapless or post-extraction.
• Insertion torque during implant placement below 35 Ncm.

Sponsors & Collaborators

• Quintas Hijós Clínica Dental: lead
• University of Salamanca: collaborator

Study Sites (1)

University of Salamanca

Salamanca, Salamanca, 37008, Spain

Location

Related Publications (1)

• Quintas-Hijos J, Perez-Pevida E. Influence of intermediate abutment height and timing of placement on marginal bone loss in single implant-supported crowns: a 12-month follow-up randomized clinical trial. Clin Oral Investig. 2025 May 8;29(6):291. doi: 10.1007/s00784-025-06364-8.

  PMID: 40335732 DERIVED

MeSH Terms

Interventions

Drug Implants; Surgery, Oral

Intervention Hierarchy (Ancestors)

Delayed-Action Preparations; Dosage Forms; Pharmaceutical Preparations; Dentistry

Study Officials

• Esteban Pérez Pevida, Dentistry

  University of Salamanca

  STUDY DIRECTOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Masking Details: Immediately after the placement of the implant, the subject was randomly assigned to one of the six treatment groups by opening a numbered sealed envelope from a computer-generated randomization list. Consequently, the surgeon was unaware of each subject's group assignment until the implant was installed. From that point onward, based on the random assignment, the intermediate abutments of the three heights were screwed with a torque lower than the implant insertion torque to the internal connection either immediately during the same installation procedure (one-abutment-one-time protocol) or delayed during the second surgery procedure at 8 weeks after the installation (two-stage protocol: submerged implant).
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Medical Director

Model Details: This controlled clinical trial aims to evaluate changes in peri-implant marginal bone levels during the first year of function around platform-switched implants placed 1.5 mm subcrestally and connected to intermediate abutments of heights 1.5, 2, and 3 mm, placed immediately at the time of the first surgery or delayed at the time of the second surgery. 54 patients received at least one single screw-retained crown on an implant replacing a posterior tooth (60 implants). The implants were divided into six treatment groups based on the height (1.5 mm; 2 mm; 3 mm) and timing of placement (immediate: surgery 1; delayed: surgery 2) of the intermediate abutment: group 1 (height 3; surgery 1), group 2 (height 2; surgery 1), group 3 (height 1.5; surgery 1), group 4 (height 3; surgery 2), group 5 (height 2; surgery 2), group 6 (height 1.5; surgery 2). Mesial and distal linear radiographic measurements (from the implant shoulder to the bone crest) were performed at five follow-up times: implant

Study Record Dates

• First Submitted: October 27, 2024
• First Posted: October 31, 2024
• Study Start: June 15, 2022
• Primary Completion: May 1, 2024
• Study Completion: June 28, 2024
• Last Updated: October 31, 2024

Record last verified: 2024-10

Locations

ES (1)