An Evaluation of Osseointegration Outcomes Around Trabecular Metal Implants in Human Maxillaries Reconstructed with Allograft and Platelet-Rich Fibrin

Trabecular Metal^TM (TM) dental implants comprise a tantalum (Ta)-based biomimetic open-cell structure designed to replicate the structural, functional, and physiological properties of cancellous bone. Yet, the current literature primarily focuses on the evaluation of osseointegration outcomes surrounding TM implants in uncompromised bone environments and/or brief periods of observation in pre-clinical models. In addition, the performance of TM implants in bony defect environments reconstructed with allogenic grafts and bioactive molecules, such as platelet-rich fibrin (PRF), has not been thoroughly investigated. This longitudinal, randomized clinical trial comprised patients presenting with completely edentulous maxillaries. Guided Bone Regeneration (GBR) was performed using a cortico-cancellous allograft/PRF agglomerate. After 26 weeks, bone biopsies were obtained, followed by the insertion of a TM implant, after which patients were allowed to heal for 52 weeks for assessment of osseointegration. Qualitatively, histomicrographs at 26 weeks confirmed the presence of newly formed bone extending from the periphery of defects and along the direct surface of the allograft. TM implant biopsies at 52 weeks demonstrated osseointegration with bone ongrowth and ingrowth at the interconnected, porous trabecular region. These histological characteristics were consistent across all patients. No metal debris was detected, and the TM implants maintained their porous structure throughout the study period. TM implants placed in PRF-augmented allograft-reconstructed maxillae fostered a conducive environment for osseointegration. By leveraging the open-cell Ta structure, robust new bone formation was achieved without signs of adverse tissue reactions.