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.
For esthetic and functional implant prosthesis, the retention type of implant should be selected considering the oral condition of the patient. However, studies on the differences in biomechanical stability of the retention type are scarce. The purpose of this study was to evaluate the biomechanical effects between retention types in implant prosthesis using 3- dimensional finite element analysis. Two retention types (Cement and Screw-Cement) were considered for the implant complex consisting of the ComOcta abutment, SS type implant, and screw all implanted in the mandibular segment of the bone block. Static finite element analysis was performed under external loads of 200 N (Vertical Load) and 100 N (Oblique Load) to each cusp tip. We measured the von-Mises stress fields in abutment and implant, and the principal strain distribution of the mandibular bone to evaluate the risk of fatigue failure in the bone. Separations between the implant components were also evaluated. The results show that with the ComOcta abutment Cement type provided enhanced stability.