Micro CT and histological analysis of the osseointegration of the trabecular 3d printed implant vs conventional implant: an animal study

Aim: This study evaluated early osseointegration of 3D-printed trabecular titanium implants versus conventional machined implants using a split-mouth animal trial. Materials and methods: Following bilateral mandibular premolar extraction and 12 weeks of healing, test implants (Ti6Al4V trabecular architecture: 600 μm pore size, 60% porosity; 3.5×10 mm) fabricated via selective laser melting and control implants (commercial machined titanium; Zimmer Biomet TSV®) were placed. Specimens harvested at 2, 6, and 12 weeks underwent micro-CT analysis and histomorphometry. Results: At 12 weeks, trabecular implants demonstrated significantly higher bone volume fraction (52.3 ± 4.1% vs. 39.7 ± 3.8%; *p* < 0.01), bone-to-implant contact (68.7 ± 6.2% vs. 47.4 ± 5.1%; *p* < 0.01), and trabecular number (2.9 ± 0.3/mm vs. 2.1 ± 0.2/mm; *p* < 0.01). Histology revealed mature bone bridging trabecular pores without fibrous encapsulation, contrasting with frequent fibrous tissue in controls. Spatial analysis showed conventional implants exhibited 14.0% greater distal axial BIC (*p* = 0.027), but equivalent apical BIC (*p* = 0.856). Conclusion: 3D-printed trabecular implants enhance early osseointegration through superior bone ingrowth and biological fixation. The 45% greater BIC at 12 weeks suggests potential to reduce healing periods in clinical prosthodontics, though site specific loading responses warrant further investigation.