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Completed

NCT Number: NCT06821308

A Randomized Controlled Clinical Trial to Assess Crestal Bone Remodeling of Four Different Implant Designs

This randomized controlled trial aimed to assess the effect of the implant neck design (microthreaded vs. non-microthreaded) as well as the type of abutment connection (internal conical vs. external flat-to-flat) on long-term crestal bone remodelling and peri-implant health. Four implants used for a bar-retained maxillary overdenture, were followed over a period of at least 6 years.

Twenty-five patients were treated with a bar-retained maxillary overdenture. Four different implants were placed, with respectively: internal connection and microthreads on the implant neck (I MT); internal connection, without microthreads (I NMT); external connection, with microthreads (E MT); and external connection, without microthreads (E NMT). Other design features, s.a. diameter, surface topography, extent of platform switch as well as the surgical and prosthetic treatment protocol were identical. Radiographic crestal bone loss (CBL), plaque score (PS), bleeding on probing (Bop) and probing pocket depth (PPD) were determined at 1 and 6 years after implant placement.

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Key information

Conditions

Dental Implant Bone Loss

Age range

21 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Ghent University

Ghent, Belgium

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Edentulous in the maxilla and sufficient bone to harvest four 4 x 9 mm implant

Exclusion criteria

  • Head -and neck radiation
  • Bisphosphonate intake
  • Limited prosthetic height

Treatment and study plan

Implant placement

Device

Each patient received 4 implants to support a bar supported overdenture. One implant is commercially available, 3 implants were experimentally made by the manufacturer for this study. The implants were similar in macro-desing, surface and platform shift but differ in microthread design and implant-abutment connection.

Primary outcomes

  1. Crestal bone loss

    Time frame: The measurements were performed at 1 and 6 years

    Radiographic measurement of crestal bone loss

Secondary outcomes

  1. Plaque

    Time frame: The measurements were performed at 1 and 6 years

    Plaque was measured at 4 sites on each implant

  2. Probing pocket depth

    Time frame: The measurements were performed at 1 and 6 years

  3. Bleeding on probing

    Time frame: The measurements were performed at 1 and 6 years

Sponsors and collaborators

Lead sponsor

University Ghent

Other

Registry information

Important dates

Study start
2015
Primary completion
2024
Study completion
2024
First posted
Feb 11, 2025
Registry last updated
Feb 11, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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