The application of 3D printed resorbable polymer membranes in extraction sockets and implant sites

15621 POSTER DISPLAY BASIC RESEARCH

Background

Hard tissue augmentation prior to and during dental implantation is one of the greatest areas of potential development. Graft materials and barrier membranes are widely utilised but offer relatively little structural support to the augmented tissue during the healing period. A directly 3D printed bioresorbable membrane has the potential to incorporate structural and design features offering support to the graft during bone formation while maintaining barrier properties.

Aim/Hypothesis

The aims of this study were to assess the feasibility and hard and soft tissue response of the placement of chair side produced sterile, resorbable polymer barrier membranes in extraction sites and buccal wall defects of dental implant sites.

Materials and Methods

Ten patients were selected with a mean range of 67 years for each of two groups. Group A required socket augmentation following extraction and the other group (B) buccal augmentation to repair a dehiscence or fenestration at the time of implant placement. Teeth were extracted and scanned as STL files (3-shape). The files were then used to design (Fusion 360 + AutoCAD) a rigid resorbable polymer graft (Polyoss R+ Ossform Pty. Australia). This was printed using a Graftmaker FDM 3D printer (Ossform Pty. Australia) as a sterile device at the chair side and fitted at the time of extraction implantation. Biooss (Geistlich AB, Switzerland) was used to fill any significant voids beneath the grafts. Characteristics of Inflammation+ Contour, Stiffness and Closure were ranked non-parametrically by the surgeon on a scale of 0-5 for each parameter at the time of surgery, 2,4,6 and 12 weeks after. Contour was further evaluated by scanning alginate impressions of each graft at placement and 12 weeks

Results

The parameters of Inflammation, Contour, Stiffness, Stability and Closure were ranked for each group (A - Socket augmentation, B- Implant placement) at 0, 2,4,6 and 12 weeks. The mean and median values for each parameter were tabulated. Mean values were rounded up or down as appropriate. The mean values for inflammation were (0 = no inflammation - 5 frank inflammation with crusting, breakdown and exudate) 0 for Groups A and B at all time intervals. Median values were 0 for both groups. Graft contour (0 for complete lack of contour - 5 as original anatomy) had a mean value of 3 for Group A and 4 for B.Graft stiffness (0 = no support just as an unsupported membrane - 5 sound bone) had mean values of 4 at all intervals for both groups. Stability (0 = moveable, slidable graft - 5 rigid, immobile graft) had mean values of 4 for Group A and 3 for Group B. Wound closure (0 for open socket - 5 is complete closure no exposure of membrane) had a mean value of 2 for Group A and 4 for Group B.

Conclusion and Clinical Implications

This preliminary clinical study demonstrates that a rigid resorbable polymer graft can be designed and fabricated at the chair side. It can be successfully placed at surgery with no evidence of inflammation. The graft offers benefits in terms of stiffness and support for the early bone formation whilst retaining the features of a barrier membrane. Further studies will provide a means of comparison with established technologies.