Periimplant Mucosa Dynamics Around Divergent and Concave Atlantis Abutment Transition Profiles

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT01871220
Recruitment Status : Active, not recruiting
First Posted : June 6, 2013
Last Update Posted : February 27, 2018
Information provided by (Responsible Party):
Christopher Barwacz, University of Iowa

Brief Summary:
The purpose of this study is to compare the effect of two different implant abutment designs on gum tissue volume changes over time after implant placement.

Condition or disease Intervention/treatment Phase
Dental Implant, Single-Tooth Esthetics, Dental Device: Concave Transition Profile Device: Divergent Transition Profile Not Applicable

Detailed Description:

This is a randomized, prospective, controlled clinical trial comparing the facial gingival profiles around Atlantis™ abutments that have either a linear "divergent" or "concave" transitional profile on the facial and proximal aspect of the abutments.

Sixty study subjects requiring replacement of a single-rooted tooth with an implant-supported restoration will be recruited.

The Osseospeed™ Plus implant will be placed for all 60 subjects, with the use of Uni healing abutments to minimize lateral tissue displacement during healing. After implant placement, but before final impressions are obtained (8 weeks post-placement), subjects will be randomized to either a "divergent" or a "concave" transmucosal abutment design. For fabrication of the experimental abutment, Atlantis™ engineers will initially design a control "divergent" prototype that will be modified with a concavity on the facial and proximal transition zones to obtain an abutment that will otherwise retain all the features of the control abutment. Engineers will measure the linear topographical changes (ΔL=Lc-Ld) of the transition zone, as well as the volumetric change (x) on the mid-facial aspect of the abutment induced by the formation of a submucosal concavity. The primary outcome of the study will be the apico-coronal change of the peri-implant mucosal zenith from prosthesis delivery to one year.

Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 60 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Study Start Date : September 2013
Estimated Primary Completion Date : September 2018
Estimated Study Completion Date : September 2018

Arm Intervention/treatment
Active Comparator: Divergent Abutment
Divergent Transition Profile
Device: Divergent Transition Profile
An Atlantis abutment is delivered with a linear transition profile

Experimental: Concave Abutment
Concave Transition Profile
Device: Concave Transition Profile
An Atlantis abutment is delivered with a concave transition profile.

Primary Outcome Measures :
  1. Peri-Implant Mucosal Zenith Changes [ Time Frame: 1, 3, 6, and 12 months ]
    Apico-coronal changes of the peri-implant mucosal zenith from prosthesis delivery to one year

Secondary Outcome Measures :
  1. Comparison of bucco-linqual soft tissue thickness [ Time Frame: 1, 3, 6, and 12 months ]
    Submarginal bucco-lingual soft tissue thickness in the peri-implant transition zone relative to a fixed reference point.

  2. Quantification of the soft tissue interface [ Time Frame: 1, 3, 6, and 12 months ]
    Quantification of the topographical and volumetric features of the interface between the peri-implant mucosa and the transition zone.

  3. Keratinized mucosa width [ Time Frame: 1, 3, 6, and 12 months ]
    Keratinized mucosa width in an apicocoronal direction at the midfacial aspect of the implant site.

  4. Gingival and Plaque Index, Bleeding on Probing, and Probing Pocket Depths [ Time Frame: 1, 3, 6, and 12 months ]
    Gingival Index (GI), Plaque Index (PI), Bleeding on probing (BOP) and probing pocket depths (PPD) at six sites (disto-lingual, mesio-lingual, mid-lingual, mesio-buccal, disto-buccal, mid-buccal).

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Ages Eligible for Study:   18 Years to 90 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • 18 years of age or greater
  • Subjects requiring replacement of a single-rooted tooth in the maxillary arch from first premolar to first premolar with an implant-supported restoration
  • Teeth adjacent (mesial and distal) to study site must consist of two stable, natural teeth without signs of periodontal bone loss (<2.0mm) and/or significant soft tissue loss
  • An opposing dentition with teeth, implants, or fixed prosthesis
  • Subjects must be willing to follow instructions related to the study procedures
  • Subjects must have read, understood, and signed the informed consent document

Exclusion Criteria:

Exclusion Criteria:

  • Insufficient interocclusal space for implant placement and/or restoration at study site
  • More than 2.0mm vertical bone loss at study site as measured from the mid-buccal crest of the bone on the adjacent teeth
  • Untreated rampant caries
  • Tobacco use free for ≤ 6 months
  • Liver or kidney disfunction/failure
  • Active severe infectious diseases that may affect normal healing and/or bone metabolism (e.g. AIDS)
  • Uncontrolled diabetes
  • Current alcohol or drug abuse
  • Need for systemic corticosteroids or any other medication that would influence post-operative healing and/or osseointegration
  • History of relevant head/neck cancer and/or radiation of the head/neck
  • Subjects who currently use bisphosphonates or have a history of bisphosphonate use
  • Subjects with metabolic bone diseases such as osteoporosis or Paget's disease of bone
  • Known pregnancy or nursing mothers
  • Unable or unwilling to return for follow-up visits for a period of 1 year
  • Unlikely to be able to comply with study procedures according to investigators judgement

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT01871220

United States, Iowa
University of Iowa College of Dentistry
Iowa City, Iowa, United States, 52242
Sponsors and Collaborators
Christopher Barwacz
Principal Investigator: Chris A Barwacz, DDS University of Iowa

Responsible Party: Christopher Barwacz, Assistant Professor, University of Iowa Identifier: NCT01871220     History of Changes
Other Study ID Numbers: 201410786
First Posted: June 6, 2013    Key Record Dates
Last Update Posted: February 27, 2018
Last Verified: February 2018

Keywords provided by Christopher Barwacz, University of Iowa:
Implant Abutments
Oral Mucosa Changes
Implant Esthetics