Evaluation of Zimmer Puros® Allograft vs. Creos™ Allograft for Alveolar Ridge Preservation
Condition: Alveolar Bone Grafting; Allograft; Dental Extraction; Dental Implant; Socket Preservation
Study type: Interventional

Summary: 
      The purpose of this study is to evaluate clinically, histologically and radiographically the
      healing of extraction sockets with Zimmer's Puros® allograft compared to creos™ (creo™ Nobel
      Biocare,), a low-cost allograft material, 90 days following exodontia.
    

Detailed description: 
      Twenty-four consecutive subjects requiring extraction of two non-adjacent molars or premolars
      located in the same jaw will be selected from the patient pool of the Center for Advanced
      Periodontology at the University of Florida, College of Dentistry.

      Preoperative Procedures: At the initial screening, the goals of the study, potential risks
      and possible benefits will be explained and each subject will be asked to sign a written
      consent statement permitting extraction of the involved teeth and the placement of Puros®
      allograft and creos™ allograft for ridge preservation. After which a complete medical and
      dental history will be obtained, a pregnancy test will be performed, and establishment of
      inclusion and exclusion criteria will be determined. If meeting all study criteria,
      examination periapical radiographs will be taken and each subject will receive oral hygiene
      instructions, prophylaxis, and full-arch alginate impressions. The study models will also be
      used to fabricate occlusal templates to permit reproducible clinical measurements of the
      alveolar ridge dimensions of the residual tooth socket.

      Surgical Protocol & Treatment Assessment: To help minimize technical variances in the
      surgical treatment protocol, the primary investigator will perform baseline and 12-week
      re-entry surgeries. Under local anesthesia, full-thickness mucoperiosteal flaps will be
      elevated; the selected teeth will be extracted atraumatically, followed by debridement of the
      sockets, and collection of all clinical measurements.The following clinical measurements will
      be made at the baseline and re-entry surgeries using standard University of North Carolina
      (UNC) manual probes (Hu-Friedy, Chicago, IL):

        1. Facial/buccal thickness (baseline, only)

        2. Distance from the occlusal template to the facial, lingual and crestal bone

        3. Socket depth (or template to crest distance at the 90-day re-entry surgery)

        4. Osseous dehiscence location and dimension

        5. Bone density (on re-entry)

      The surgeon will then preserve each site with either Puros® allograft creos™ allograft.
      Puros® allograft will be placed into half of the extraction sockets to the level of the
      osseous crest. A bovine pericardium membrane (CopiOs ®Pericardium) will be then placed to
      cover the bone graft material. Primary closure will be achieved in all cases. The site will
      be sutured with 4.0 PTFE sutures. The other extraction sites will receive the same treatment
      but with creos™ allograft. Participants will be prescribed a 10 day regimen of Ibuprofen
      (2.4g/day) and antibiotics (amoxicillin (1.5g/day) or clindamycin (0.6g/day)) unless other
      allergies are present. Subjects will be instructed to change their diet to semi-liquid for 48
      hours, followed by soft foods for the first 2-weeks. Subjects will also be instructed to
      begin rinsing with warm water, as needed, and to resume their normal oral hygiene routine the
      day after surgery in all areas except the surgical site.

      At 2-week post-surgery, the extraction sites will be inspected and gently cleaned with
      saline-soaked gauze, health histories will be reviewed, oral hygiene instructions will be
      repeated, photographs will be taken; and a plaque score will be recorded. Cone beam CT images
      will be performed 2 weeks and 12 weeks post-operative. All imaging will be done using the
      Kodak limited view CBCT to minimize the subjects' exposure to radiation.

      Soft tissue healing will be assessed at 2, 8 and 12 weeks with a wound-healing index (WHI)
      according to the following scheme: score "1" for uneventful wound healing with no gingival
      edema, erythema, suppuration, discomfort or graft exposure; score "2" for uneventful wound
      healing with slight gingival edema, erythema, or discomfort, but minimal loss of graft and no
      suppuration; score "3" for poor wound healing with significant gingival edema, erythema,
      discomfort, loss of graft or any suppuration.

      Re-entry surgery will be performed at 12 weeks, and all clinical measurements will be
      repeated. Crestal flapless soft tissue and bone core biopsies approximately 2.7 x 10 mm in
      size will be removed with a 3.2 mm trephine drill from the area corresponding to the center
      of the previous extraction from the crest of the ridge using the occlusal template as a
      guide.

      The cores will be placed in bottles of 10% neutral buffered formalin (NBF) for fixation, and
      then labeled with a 5-digit number in order to permit masked histomorphometric analysis.
      Analysis will be performed in the outer aspect of the bone cores, which correspond to the
      bone surface that will contact the dental implants at the time of placement. Zimmer TSTV
      implants will be placed at the same time the second re-entry procedure is done. All implants
      will be placed according to the manufacturer's specifications. Restorative treatment will be
      initiated 90 days after implant placement.
    

Intervention name(s): Zimmer Puros Cancellous Allograft; Nobel Biocare Creos Cancellous Allograft
Intervention type(s): Device; Device
Intervention description(s): Right side will have an extraction followed by an allogenic bone graft zimmer puros followed by implant placement.; Left side will have an extraction followed by an allogenic bone nobel biocare creos graft followed by implant placement.
Allocation: Non-Randomized
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Treatment