Alveolar Ridge Preservation Using Collagen Material and Allograft
Condition: Alveolar Ridge Preservation
Study type: Interventional

Summary: 
      Seven Patients who need implants to replace non-restorable teeth in the esthetic zone.

      Intervention Group (1): Seven extraction sockets that received the collagen matrix (Collagen
      cone) for alveolar ridge preservation.

      Comparison Group (2): Seven extraction sockets that were treated with mineralized
      cortico-cancellous bone allograft for alveolar ridge preservation.

      Outcome

        1. Alveolar ridge preservation both in height and in width to improve implant success rate

             -  The height of alveolar ridge was assessed clinically using a periodontal probe.

             -  The width of the alveolar ridge was measured after three months after extraction
                using a caliper clamp.

             -  Changes in the width and height of alveolar bone were evaluated in merged axial and
                sagittal views using the I-CAT superimposition system (CBCT).

                2- Evaluation of newly formed bone quality was performed by histological
                examination and histomorphometric analysis.

                3- Immuno-histochemical staining was done using polyclonal antibody to detect
                (BMP-2) marker of bone formation
    

Detailed description: 
      The aim of the present study was to compare three months post-extraction augmented ridge
      using collagen matrix versus mineralized cortico-cancellous bone allograft. This comparison
      was done clinically, histologically, immunohisto-chemically and radiologically.

      • Clinical parameters included; vertical bone height and bone width that were recorded at
      baseline and at three months after extraction. Moreover, histomorphometric parameters
      included; area fraction of osteoid and mature bone three months after extraction by
      histomorphometric analysis. Immunohistochemical analysis using polyclonal antibody to detect
      BMP-2 marker of bone formation. Radiographic parameters included superimposition of baseline
      CBCT, three months after extraction and another one six months after loading with subsequent
      measurement of bone height, bone width and bone density.

      A core biopsy was taken three months after tooth extraction which has undergone
      histomorphometric and immunohistochemical analysis; implant placement was also done at the
      same time.

      In the present study, it was found that the mean bone height decreased with a higher percent
      in collagen matrix group than mineralized cortico-cancellous bone allograft group with a non
      significant difference between both groups.

      In addition, this study showed that the mean bone width decreased more in collagen matrix
      group than mineralized cortico-cancellous bone allograft group with a non significant
      difference between them.

      Moreover, in the present study, Histomorphometric analysis revealed new bone trabeculae
      formation with osteoblastic rimming, the surrounding fibrous tissue is cellular and remnants
      of the graft materials was detected , with no marked difference in the amount of newly formed
      bone between two groups .

      Regarding immunohistochemical analysis in both groups, the osteoblasts in the fibrous tissue
      and osteocytes in newly formed bone are showing nuclear staining, with increasing area of
      immunopositive cells in mineralized cortico-cancellous bone allograft group.

      Radiographically, CBCT superimposition revealed that a greater percent decrease in bone
      height was denoted in collagen matrix than mineralized cortico-cancellous bone allograft
      group with a significant difference between both groups after 3 and 6 months.

      Accordingly bone width showed a higher decrease in mineralized cortico-cancellous bone
      allograft group than Collagen matrix group with a non significant difference between both
      groups after 3 and 6 months.

      Finally, bone density showed a greater decrease in Collagen matrix group than mineralized
      cortico-cancellous bone allograft group with a non significant difference after 3 months but
      significant difference was found after 6 months between both groups.
    

Intervention name(s): Allograft; Collagen cone
Intervention type(s): Other; Other
Intervention description(s): Corticocancellous mineralized allograft; Collagen matrix
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Group (1): Seven extraction sockets that received the collagen matrix (Collacone) for alveolar ridge preservation.
Group (2): Seven extraction sockets that were treated with mineralized cortico-cancellous bone allograft (Maxgraft) for alveolar ridge preservation
Masking: Single (Outcomes Assessor)
Primary purpose: Treatment
Keywords: Alveolar ridge preservation; Allograft; Collagen cone