Periimplant Mucosa Dynamics Around Divergent and Concave Atlantis Abutment Transition Profiles

Study Overview
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Brief Summary
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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.

Detailed Description
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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.

Official Title
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Peri-implant Mucosa Dynamics Around Divergent and Concave Atlantis™ Abutment Transition Profiles.

Conditions
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Dental Implant, Single-Tooth, Esthetics, Dental

Intervention / Treatment
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* Device: Concave Transition Profile
* Device: Divergent Transition Profile


Participation Criteria
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Eligibility Criteria
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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

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Divergent Abutment<br>Divergent Transition Profile | Device: Divergent Transition Profile<br>* An Atlantis abutment is delivered with a linear transition profile<br>|
| Experimental: Concave Abutment<br>Concave Transition Profile | Device: Concave Transition Profile<br>* An Atlantis abutment is delivered with a concave transition profile.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Peri-Implant Mucosal Zenith Distance (in Millimeters) at the Concave/Divergent Abutment Sites | Determine if there is a difference in soft tissue peri-implant zenith changes (in millimeters) for the concave/divergent abutment sites, specifically between at delivery and 1, 3, 6, and 12 months after Atlantis Abutment and Restoration Delivery. This measurement is taken using a standardized stereotactic digital photography system that allows for increased measurement accuracy and precision, specifically with the Canfield Dental Camera, Canfield Imaging Systems. | Delivery, and 1, 3, 6, and 12 months after Atlantis Abutment and Restoration Delivery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Submarginal Buccal-lingual Thickness (Millimeters) in the Peri-implant Transition Zone Relative to a Fixed Reference Point After Prosthesis Delivery | Determine if there is a difference in submarginal buccal-lingual soft tissue thickness in the peri-implant transition zone relative to a fixed reference point, specifically at baseline and 1, 3, 6, and 12 months after Atlantis Abutment and Restoration Delivery. This measurement is taken using a standardized stereotactic digital photography system that allows for increased measurement accuracy and precision, specifically with the Canfield Dental Camera, Canfield Imaging Systems. | Baseline and 1, 3, 6, and 12 months after Atlantis Abutment and Restoration Delivery | 
| Keratinized Mucosa Width (Millimeters) at the Midfacial Aspect of the Implant Site. | Determine if there is a difference in Keratinized Mucosa Width (millimeters) in the apico-coronal direction at the midfacial aspect of the implant site, specifically at baseline and 1, 3, 6, and 12 months after Atlantis Abutment and Restoration Delivery. This measurement is taken using a standardized stereotactic digital photography system that allows for increased measurement accuracy and precision, specifically with the Canfield Dental Camera, Canfield Imaging Systems. | Baseline and 1, 3, 6, and 12 months after Atlantis Abutment and Restoration Delivery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Implant Abutments, Oral Mucosa Changes, Implant Esthetics