(45) 3D-printed resorbable PCL/β-TCP membrane for guided bone regeneration in peri-implant dehiscence defect

Introduction: To overcome the limitations of existing various membranes in guided bone regeneration (GBR), recent studies have focused on developing resorbable membranes with the space-maintaining mechanical property and appropriate biological properties using different fabrication methods and synthetic biodegradable materials. The advancement of a three-dimensional (3D) printing technology in the field of bone tissue engineering promises the evolution of bioresorbable membranes. The aim of this study was to evaluate the clinical and radiographic outcomes of osseous changes following the application of GBR technique using a 3D-printed resorbable polycaprolactone/ β-tricalcium phosphate (PCL/β-TCP) membrane in comparison with a collagen membrane on peri-implant dehiscence defects.

Methods: For a total of 10 patients, alveolar bone augmentation was accomplished with either pre-shaped 3D-printed PCL/β-TCP membranes as a test group or collagen membranes as a control group in conjunction with bovine-derived xenograft. Virtual implant planning software was used to plan prosthetically driven implant positions in all cases. The cone-beam computed tomography (CBCT) scans were performed at two points, immediately after implant placement (baseline) and at re-entry surgery after 4-5 months of healing. The horizontal thickness (HT0, HT2, HT4), vertical thickness (VT), and VT at 45° angle (45-VT) of the augmented hard tissue were measured to compare alveolar bone changes through CBCT images as follows: HW0 at the level of the implant shoulder, HW2 and HW4 at respective depths of 2mm and 4mm apical to the implant shoulder, VT and 45-VT were measured upward from the implant shoulder.

Results: Throughout the healing period, surgical sites showed the absence of soft-tissue dehiscence and membrane exposure, and there were no signs and symptoms of severe post-operative complications. The intergroup CBCT comparison between the test and control group showed a statistically significant difference (p < 0.05) in mean horizontal and vertical bone dimensions observed at HW0, VT, and 45-VT. A significantly higher amount of bone regeneration was observed in the 3D-printed PCL/β-TCP membrane group. However, in comparison between the first and second surgeries for the control and test group, no statistically significant differences were found.

Conclusions: Within the limitations of the present study, peri-implant dehiscence defects could be effectively treated with a pre-shped 3D-printed resorbable PCL/β-TCP membrane in terms of stability and improved bone regeneration at both horizontal and vertical augmented regions.

* This work was supported by the Korea Medical Device Development Fund grant funded by the Korea government (KMDF_PR_20200901_0299) and the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (NRF-2019R1A2C1086515).

Lead Author's Contributions to the Research Project. : The Lead Author was responsible for designing the sutdy, the data collection, interpreting the data and the composition of the abstract.