Histomorphometric and Tomographic Assessment on the Influence of the Placement of a Collagen Membrane Subjacent the Sinus Mucosa After Maxillary Sinus Floor Augmentation

Study Overview
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Brief Summary
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the purpose of the study is to look for differences in dimensional variations of augmented maxillary sinuses with or without the placement of a collagen membrane subjacent the sinus mucosa.

Detailed Description
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Material and Methods: After the elevation of the maxillary sinus mucosa, a collagen membrane with standard dimensions will be placed at the test sites subjacent the sinus mucosa and the elevated space will be filled with a xenograft, both test and control groups. A collagen membrane will be placed to cover the antrostomy at both groups and sutures will be provided to close the wound. After six months of healing, mini-implants will be installed. After 9 months, biopsies containing the mini-implants will be harvested for histomorphometric analyses. CBCTs will be taken for all patients before surgery (T0), after 1 week from sinus floor augmentation (T1) and after 9 months of healing (T2). Osseointegration of the mini-implants and dimensional changes over time of soft and hard tissues will be evaluated on the CBCTs.

Official Title
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Histomorphometric and Cone Beam Computed Tomography Assessments on the Influence a Collagen Membrane Placed Subjacent the Sinus Mucosa After Maxillary Sinus Floor Augmentation. A Randomized Clinical Trial.

Conditions
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Alveolar Bone Loss

Intervention / Treatment
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* Procedure: Maxillary sinus augmentation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: presence of an edentulous atrophic zone in the posterior segment of the maxilla height of the sinus floor ≤4 mm desiring a prosthetic restoration of the zone using a fix prosthesis supported by implants; ≥ 21 years of age good general health no contraindication for oral surgical procedures not being pregnant Exclusion Criteria: present a systemic disordered had a chemotherapic or radiotherapeutic treatment are smokers >10 cigarettes per day have an acute or a chronic sinusitis had a previous bone augmentation procedures in the zone of interest.

Ages Eligible for Study
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Minimum Age: 21 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: Clinical trial
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: test site<br>The sinus mucosa will be elevated and, at the test sites, a collagen membrane will be placed subjacent the sinus mucosa | Procedure: Maxillary sinus augmentation<br>* Maxillary sinus augmentation procedures have become increasingly popular procedures before placement of dental implants in posterior maxillae that have suffered severe bone loss due to sinus pneumatization, alveolar bone atrophy, or trauma.<br>* Other names: maxillary sinus lift, maxillary sinus elevation;|
| Experimental: control site<br>The sinus mucosa will be elevated and, at the control sites, a collagen membrane will not be placed subjacent the sinus mucosa | Procedure: Maxillary sinus augmentation<br>* Maxillary sinus augmentation procedures have become increasingly popular procedures before placement of dental implants in posterior maxillae that have suffered severe bone loss due to sinus pneumatization, alveolar bone atrophy, or trauma.<br>* Other names: maxillary sinus lift, maxillary sinus elevation;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changing in height of the elevated zone | Measurements will be assessed in the medial, middle and lateral regions of the elevated zone using the cone beam computerized tomographies (CBCTs) taken in various periods. | The CBCTs will be taken before surgery (T0) and 1-week (T1) and 9 months (T2) after surgery. | 
| New bone-to-implant contact | Measurements will be assessed between the most coronal (B) and the most apical (A) contacts of new bone to the implant surface. | Mini-implants will be installed six months after sinus lifting and retrieved after three months of healing. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changing in mucosa thickness | Measurements will be assessed in the cone beam computerized tomographies (CBCTs) taken in various periods. Comparisons among the CBCTs of each participants will be performed. | The CBCTs will be taken before surgery (T0) and 1-week (T1) and 9 months (T2) after surgery. | 
| New bone density around the mini-implant, from B to A and up to a distance of 400 µm from the implant surface. | Measurements will be assessed using a point counting procedure, superposing a lattice with squares of 50 µm over the histological image. | Mini-implants will be installed six months after sinus lifting and retrieved after three months of healing | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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maxillary sinus, collagen membrane, CBCT, Histology