Dimensional Changes in Single Crowns Supported by Short Transmucosal Implants With Diverging or Converging Neck Profiles in the Esthetic Zone

Study Overview
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Brief Summary
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The goal of the present randomized clinical trial is to assess the long-term osseous and peri-implant soft tissue changes as well as the success rate of short implants (6 mm) with a converging collar with micro threads or a diverging polished collar placed in the esthetic zone of the maxilla on partially edentulous patients. The main questions it aims to answer are: what are the long-term bone and soft tissue changes around implants with a converging collar with micro threads compared to a diverging polished collar placed in the esthetic zone of the maxilla? What is the success rate of implants with a converging collar with micro threads compared to a diverging polished collar placed in the esthetic zone of the maxilla? Dental implants with a converging collar with micro threads or a diverging polished collar will be placed in the esthetic zone of the maxilla of the included participants and the measurements regarding the bone and soft tissue level will be compared.

Detailed Description
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The objectives of the present randomized clinical trial are to evaluate the clinical and radiographic changes over time of hard and soft tissues around implants with a convergent or divergent collar. Twenty volunteer participants with two edentulous regions in the maxillary esthetic zone (from the right second premolar to the left second premolar) will be included in the study. Two implants will be randomly installed, one with a convergent collar and one with a divergent collar. After 3 months of healing, individual crowns will be installed. At each visit the following parameters will be evaluated: plaque index, probing depth, bleeding on probing, the recession of the mucosal margin, intraoral radiographs, likewise control CBCT, and impressions will be performed. The visit will take place at 6 and 12 months and then annually for a minimum of 3 years. Changes at the level of the marginal bone will be assessed overtime on the radiographs. Dimensional changes will be clinically evaluated during control evaluations and later through digital impressions.

Official Title
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Long-term Dimensional Changes in Single Crowns Supported by Short (6 mm) Transmucosal Implants With Divergent or Convergent Neck Profiles in the Esthetic Zone. A Randomized Randomized Controlled Clinical Trial

Conditions
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Edentulous Alveolar Ridge

Intervention / Treatment
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* Procedure: Dental implants placement


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Presence of at least two edentulous areas in the esthetic region of the maxilla (from right to left from second premolar to premolar, preferably first premolars and incisors) Alveolar bone ≥ 8 mm in height and ≥ 5 mm in thickness assessed on CBCT. Age of ≥ 21 years. Need for an implant-supported prosthetic restoration. Be in good general health with no contraindications to oral surgical procedures. Not be pregnant. Patients who agree to participate in the study and sign the informed consent. Exclusion Criteria: The presence of any uncontrolled systemic disease. History of past or ongoing chemotherapeutic or radiotherapeutic treatments. Heavy smokers (>10 cigarettes per day). Previous bone regeneration procedures in the area of interest

Ages Eligible for Study
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Minimum Age: 21 Years
Maximum Age: 60 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
Interventional Model Description: The study is a split-mouth randomized controlled trial. One implant with a converging collar with micro threads or a diverging polished collar will be installed in each patient according to randomization in the esthetic region of the upper jaw ( between the second premolars ). It will be restored with individual crowns after three months of healing. Both implants will be placed with the rough margin of  1 mm subcrestally.
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: dental implant with a convergent collar<br>One implant with a converging collar with micro threads will be installed in each patient according to the site randomization in the esthetic region of the upper jaw (between the second premolars). | Procedure: Dental implants placement<br>* surgery for placement of two one-piece trans gingival implants<br>* Other names: implant supported prosthetic restoration;|
| Active Comparator: dental implant with a divergent collar<br>One implant with a diverging polished collar will be installed in each patient according to the site randomization in the esthetic region of the upper jaw ( between the second premolars). | Procedure: Dental implants placement<br>* surgery for placement of two one-piece trans gingival implants<br>* Other names: implant supported prosthetic restoration;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| height of the periimplant bone tissues | The height of the periimplant bone tissues will be evaluated in the intraoral radiographic images, cone beam tomography, and the three-dimensional images obtained from the digital prints | baseline | 
| height of the periimplant bone tissues | The height of the periimplant bone tissues will be evaluated in the intraoral radiographic images, cone beam tomography, and the three-dimensional images obtained from the digital prints | 3 years follow up | 
| height of the periimplant soft tissues | The height of the periimplant soft tissues will be evaluated in the intraoral radiographic images, cone beam tomography, and the three-dimensional images obtained from the digital prints | Baseline | 
| height of the periimplant soft tissues | The height of the periimplant soft tissues will be evaluated in the intraoral radiographic images, cone beam tomography, and the three-dimensional images obtained from the digital prints | 3 years follow up | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Plaque index | to score the plaque accumulation of plaque around implants will be used the Mombelli et al index | 1 year | 
| Plaque index | to score the plaque accumulation of plaque around implants will be used the Mombelli et al index | 3 year | 
| Bleeding on probing | During the probing, the bleeding on probing will be registered in the periodontal record. | 1 year | 
| Bleeding on probing | During the probing, the bleeding on probing will be registered in the periodontal record. | 3 year | 
| Probing depth | A calibrated probe will be used to measure the probing depth in all teeth annually. | 1 year | 
| Probing depth | A calibrated probe will be used to measure the probing depth in all teeth annually. | 3 year | 
| Implant success rate | The criteria to evaluate the success rate will be if there was no persistent and/or irreversible signs or symptoms such as pain, infection, neuropathies, or paresthesia, no peri-implant infection with suppuration, no mobility, and no continuous radiolucency around the implant. | 1 year | 
| Implant success rate | The criteria to evaluate the success rate will be if there was no persistent and/or irreversible signs or symptoms such as pain, infection, neuropathies, or paresthesia, no peri-implant infection with suppuration, no mobility, and no continuous radiolucency around the implant. | 3 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Maxilla, Partially edentulous, Dental implant, Implant supported prosthesis