Development of a Hybrid Composite Structure and Bioreactor for Enhanced Bone Regeneration in Dental Implants

Dental implant surgery usually takes over 6 to 9 months, with 3 to 6 months specifically allocated for osseointegration between the implant and the surrounding bone. To expedite this process, we developed an innovative hybrid composite structure and a bioreactor. This hybrid structure features an assembly-type implant combined with a 3D-printed polycaprolactone (PCL) scaffold. The implant was redesigned in a modular format to enable the insertion of a scaffold between components, facilitating bone-to-bone contact instead of metal-to-bone contact, which enhances osseointegration. The PCL scaffold was coated with polydopamine (PDA) to improve cell adhesion. Additionally, a bioink that mimics bone composition, consisting of type I collagen and nano-hydroxyapatite (nHA), was incorporated into the scaffold. To support cell maturation within the scaffold, we developed a hydrostatic pressure bioreactor system that applies uniform compressive stress to complex 3D structures. We assessed cell viability in the scaffold using the CCK-8 assay, and SEM imaging confirmed the effectiveness of the PDA coating. Furthermore, we evaluated osteogenic differentiation through ALP activity and calcium quantification assays under both static and dynamic stimulation conditions.