Healing of Post-ext Sites Using Bovine Bone Mineral: a CBCT and Histologic RCCT
Condition: Loss of Teeth Due to Extraction; Edentulous Alveolar Ridge
MeSH terms: Tooth Loss
Study type: Interventional
Phase: Phase 4

Summary: 
      Aim of the present investigation will be to evaluate the role of a bovine-bone mineral and a
      collagen membrane as ridge augmentation procedure following tooth extraction. 20 consecutive
      adult patients, requiring tooth extraction in the frontal area of the upper and lower arch
      maxilla (from second premolar to second premolar), will be enrolled into the study.

      After tooth extraction, sockets will be randomized and divided into two groups: in Group A
      the socket will be grafted with Bio-Oss Collagen , in Group B the sockets will be grafted
      with BioOss granules (small granules). The graft will be covered with porcine collagen
      membrane (BioGide). Then, the flap will be sutured.

      MEASUREMENTS:

      The end of the study will be fixed at the 6 months evaluation after tooth extraction.
      Impression will be taken before tooth extraction and after 6 months in order to create cast
      models. On the cast models, using reference PVC (polyvinylchloride) guides, the horizontal
      dimension of the soft tissues will be measured. One measurement per tooth will be recorded,
      at T0 (before extraction) and T2 (after 6 months).

      A 3D radiological image, using the CBCT technique, will be obtained at the end of the
      surgical stage T1 (extraction + bone graft) and after 6 months of healing. Superimposition
      will be performed in order to measure hard tissue remodelling.

      After six months (T6), a a biopsy specimen will be also harvested for that augmented
      extractions sockets on which an implant installation has been previously planned.
    

Detailed description: 
      Both animal and human studies have clearly demonstrated that the healing of post extraction
      sites usually results in pronounced alveolar ridge resorption, that mostly stabilized after 4
      to 6 months. The marked tri-dimensional alterations of the ridge volume may jeopardize
      patients' aesthetics and create anatomical difficulties for further implant placement.

      Aim of the present investigation will be to evaluate the role of a bovine-bone mineral and a
      collagen membrane as ridge augmentation procedure (intended as "increase of the ridge volume
      beyond the skeletal envelope existing at the time of extraction") following tooth extraction.
      Furthermore, the authors aim to evaluate as the collagen membrane acts when used for
      "open-healing".

      20 consecutive adult patients, requiring tooth extraction in the frontal area of the upper
      and lower arch maxilla (from second premolar to second premolar), will be enrolled into the
      study.

      After local anesthesia, a buccal full thickness flap will be elevated, and then the hopeless
      teeth will be gently extracted. All granulation tissue will be removed from the alveolus,
      that will be rinsed with saline. At this time the post-extraction sockets will be randomized
      and divided into two groups: in Group A the socket will be grafted with Bio-Oss Collagen , in
      Group B the sockets will be grafted with BioOss granules (small granules) using the Bio-Oss
      Pen device.

      The graft will be covered with porcine collagen membrane (BioGide). Then, the flap will be
      sutured. The sutures (single sutures) will involve only the interdental gingival tissue, and
      no attempt will be done to reach a complete soft tissue closure of the sockets: in the
      alveolus area BioGide will be mostly left exposed, intended as "open healing" for second
      intention wound healing.

      The patient swill assume antibiotics per 6 days (Amoxicillin + Clavulanate 1gr), and will
      rinse with Digluconate Chlorhexidine 0.20% per 14 days. At day 14 the sutures will be
      removed. If, at this moment, the gingiva over the graft will not be completely closed, the
      patient will use Digluconate Chlorhexidine 0.20% until the secondary closure will be
      completed.

      MEASUREMENTS:

      The end of the study will be fixed at the 6 months evaluation after tooth extraction
      (corresponding to the planned time for implant installation).

      Impression will be taken before tooth extraction and after 6 months in order to create cast
      models. On the cast models, using reference PVC guides, the horizontal dimension of the soft
      tissues (measured perpendicular to the tangent of the dental arch at the midpoint of the
      extraction site as the distance between the most prominent points buccally and orally) will
      be measured. One measurement per tooth will be recorded, at T0 (before extraction) and T2
      (after 6 months).

      A 3D radiological image, using the CBCT technique, will be obtained at the end of the
      surgical stage T1 (extraction + bone graft) and after 6 months of healing. Using a diagnostic
      software, superimposition will be performed in order to measure hard tissue remodelling.

      After six months (T6), a a biopsy specimen will be also harvested for that augmented
      extractions sockets on which an implant installation has been previously planned, with the
      purpose of an histologic and histomorphometric evaluation (measurement of new bone formation
      and measurement of remaining BioOss granules). The biopsy will be taken exactly in the area
      where dental implants will be placed.
    

Intervention name(s): Ridge Augmentation
Intervention type(s): Procedure
Intervention description(s): After tooth extraction, the sockets will be filled with bovine bone mineral and covered with a porcine collagen membrane
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary purpose: Treatment
Keywords: Tooth extraction; Ridge Preservation; Ridge Augmentation; Guided Bone Regeneration