Guided Bone Regeneration Around Immediate Implants

Study Overview
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Brief Summary
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An important result of healing after tooth extraction is a reduction in dimensions of the remaining bone at that site. This reduction of bone volume precludes successful restoration of the space using a dental implant. Bone augmentation has shown promise in clinical reports to reduce this loss of bone volume, thus allowing implant placement and restoration. The purpose of this study is to evaluate the clinical and radiographic outcomes of guided bone regeneration around dental implants placed in fresh extraction sockets.

Detailed Description
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Aim: The purpose of this clinical study is to investigate the effect of a non-resorbable polytetrafluoroethylene (PTFE) membrane on immediate implant placement in the esthetic zone. Material and Methods: Systemically healthy subjects presenting with a hopeless tooth in the maxillary premolar or anterior region will be recruited in the study. Following a minimally traumatic tooth extraction, subjects will be randomly distributed into one of two treatment groups, a Membrane (Test) or a No Membrane (Control) group. Both groups will receive immediate placement of an implant along with placement of a bone graft material to fill the spaces around the implant. Sites in the test group will receive a non-resorbable PTFE membrane over the socket, whereas those in the control group will receive a collagen dressing over the socket. At sites in the test group, the membrane will be removed at 4 weeks. A second stage surgery and placement of a provisional restoration will be carried out 4 months after implant placement. Final restorations will be placed 3 months after placement of the provisional restoration. Clinical and radiographic measurements will be performed at baseline, implant placement, placement of provisional and final restorations and at the 5-month recall visit.

Official Title
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The Effectiveness of the Cytoplast Technique in Preventing Bone Loss Around Immediate Implant Placement in the Esthetic Zone. A Randomized Clinical Trial.

Conditions
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Missing Tooth

Intervention / Treatment
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* Procedure: Minimally Traumatic Tooth Extraction
* Device: Immediate Implant Placement
* Biological: Bone Graft Placement
* Biological: Membrane placement
* Biological: Collagen plug placement
* Drug: Medications


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Males and females aged 18 or older. Systemically healthy (American Society of Anesthesiologists I or II). Subjects will have one or more anterior or premolar teeth with a hopeless prognosis, with adjacent and opposing teeth present. Compliance with all requirements in the study and signing the informed consent Exclusion Criteria: Active acute infection at the extraction site (e.g., sinus tract, swelling) Absence of sufficient mesio-distal width to place an implant as per the study protocol. Absence of sufficient bone height to house a 10mm long implant. The subject lacks a stable occlusion and/or a healthy periodontium. Current smokers or quit smoking less than one year Chronic use of medications known to affect the periodontal status (calcium antagonists, anticonvulsives, immunosuppressives, anti-inflammatory medications) Pregnancy or lactating mothers Current orthodontic or periodontal treatments History of alcoholism or drug abuse Untreated deep carious lesions or defective restorations that can potentially exacerbate during the course of the study Diseases of the immune system or any medical condition that may influence the outcome (uncontrolled diabetes (HbA1c >7) Bone disorders (hyperparathyroidism, osteoporosis, or Paget's disease) Neurologic or psychiatric disorders, systemic infections A history of IV bisphosphonate use.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 100 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: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Membrane<br>Test (membrane): Extraction and immediate implant placement will be performed. The gaps between the implant and socket walls will be filled with a bone graft material. Sites in the test group will receive a high-density PTFE (d-PTFE) membrane over the socket. | Procedure: Minimally Traumatic Tooth Extraction<br>* The surgeon will perform a minimally traumatic tooth extraction in the following fashion. Intrasulcular incisions will be performed with at 15-C scalpel around the tooth to be extracted. A periotome will then be introduced into the periodontal ligament space in order to sever the subcrestal attachment and expand the periodontal ligament space. Elevators will be used to initiate luxation of teeth. After significant mobility has been achieved through elevation, forceps will be used only to deliver the tooth. Finally, the socket will be curetted to remove all granulomatous tissue and irrigated with sterile isotonic saline solution.<br>Device: Immediate Implant Placement<br>* A threaded titanium alloy implant with an internal hex connection and a Resorbable Blast Texturing (RBT) surface (Tapered Internal® Implant System, Biohorizons, Inc., Birmingham, AL, USA) will be placed using a surgical guide. Implant diameter of 3.8mm with lengths of either 12 or 15mm will be used. Implants will be placed approximately 3-4mm below the free gingival margin or 2-3mm below the cemento-enamel junction of adjacent teeth.<br>Biological: Bone Graft Placement<br>* Circumferential defects or dehiscences around the immediately placed implant will be grafted. enCore™ Combination Allograft (Osteogenics Biomedical, Lubbock, Texas, USA) will be used as the bone graft material.<br>Biological: Membrane placement<br>* A non absorbable d-PTFE membrane (Cytoplast® TXT-200, Osteogenics Biomedical, Lubbock, Texas, USA) will be trimmed to an appropriate size and shape to completely cover the implant site, and extend about 3-5mm beyond on the facial aspect. The membrane will be tucked under the sub-periosteal flap. Care will be taken to ensure that the membrane is resting on bone all around the socket margins. The membrane will be kept a minimum of 1.5mm from the adjacent tooth roots in the interdental area.<br>Drug: Medications<br>* Patients will be given amoxicillin 500mg 2 days prior to the surgery and will then continue for every 8 hours for 10 days. Patients will also take Ibuprofen 600mg every 6 hours for the first 3 days following the surgery, and then as needed for pain. Patients will also receive a prescription for Vicodin as needed for pain, every 4 to 6 hours<br>|
| Active Comparator: Collagen plug<br>Control (collagen plug): Extraction and immediate implant placement will be performed. The gaps between the implant and socket walls will be filled with a bone graft material. Sites in the control group will receive a collagen wound dressing over the socket. | Procedure: Minimally Traumatic Tooth Extraction<br>* The surgeon will perform a minimally traumatic tooth extraction in the following fashion. Intrasulcular incisions will be performed with at 15-C scalpel around the tooth to be extracted. A periotome will then be introduced into the periodontal ligament space in order to sever the subcrestal attachment and expand the periodontal ligament space. Elevators will be used to initiate luxation of teeth. After significant mobility has been achieved through elevation, forceps will be used only to deliver the tooth. Finally, the socket will be curetted to remove all granulomatous tissue and irrigated with sterile isotonic saline solution.<br>Device: Immediate Implant Placement<br>* A threaded titanium alloy implant with an internal hex connection and a Resorbable Blast Texturing (RBT) surface (Tapered Internal® Implant System, Biohorizons, Inc., Birmingham, AL, USA) will be placed using a surgical guide. Implant diameter of 3.8mm with lengths of either 12 or 15mm will be used. Implants will be placed approximately 3-4mm below the free gingival margin or 2-3mm below the cemento-enamel junction of adjacent teeth.<br>Biological: Bone Graft Placement<br>* Circumferential defects or dehiscences around the immediately placed implant will be grafted. enCore™ Combination Allograft (Osteogenics Biomedical, Lubbock, Texas, USA) will be used as the bone graft material.<br>Biological: Collagen plug placement<br>* A bio-absorbable collagen wound dressing (CollaPlug®, Zimmer Dental, Carlsbad, CA, USA) will be trimmed to the appropriate size, so as to cover the socket<br>Drug: Medications<br>* Patients will be given amoxicillin 500mg 2 days prior to the surgery and will then continue for every 8 hours for 10 days. Patients will also take Ibuprofen 600mg every 6 hours for the first 3 days following the surgery, and then as needed for pain. Patients will also receive a prescription for Vicodin as needed for pain, every 4 to 6 hours<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Thickness of Buccal Bone | Change of buccal bone volume over study duration | One year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Interproximal Bone Levels | Change of interproximal marginal bone loss (mean of mesial and distal sites) | One year | 
| Pink Esthetic Score | Pink esthetic score per Furhauser et.al. measured at study conclusion where based on seven variables: mesial papilla, distal papilla, soft-tissue level, soft-tissue contour, alveolar process deficiency, soft-tissue color and texture (Fig. 1). Each variable was assessed with a 2-1-0 score, with 2 being the best and 0 being the poorest score. Thus a maximum score of 14 is best, and 0 is the worst. | One year |