Synergistic Effects of Novel Superparamagnetic/Upconversion HA Material and Ti/Magnet Implant on Biological Performance and Long‐Term In Vivo Tracking

Abstract

To solve the clinical challenges presented by the long‐term tracking of implanted hydroxyapatite (HA) bone repair material and to investigate the synergistic effects of superparamagnetic HA and a static magnetic field (SMF) on the promotion of osteogenesis, herein a new type of superparamagnetic/upconversion‐generating HA material (HYH‐Fe) is developed via a two‐step doping method, as well as a specially‐designed titanium implant with a built‐in magnet to provide a local static magnetic field in vivo. The results show that the prepared HYH‐Fe material maintains the crystal structure of HA and exhibits good cytocompatibility. The combined use of the superparamagnetic HYH‐Fe material and SMF can effectively and synergistically promote osteogenesis/osteointegration surrounding the Ti implants. In addition, the HYH‐Fe material exhibits distinct advantages in terms of both long‐term fluorescence tracking and microcomputed tomography (micro‐CT) tracking. The new material and tracking strategy in this study provide scientific feasibility and will have important clinical value for long‐term tracking and evaluation of implanted materials and the bone repair effect.

Pro-osteogenesis and in vivo tracking investigation of a dental implantation system comprising novel mTi implant and HYH-Fe particles

“…2 A and Fig. S2 ), which is caused by the 700 °C activation to induce its upconversion fluorescence [ 7 , 27 ]. Both the diffraction spot rings of the (002) and (211) crystal planes in the inset SAED pattern in Fig.…”

“…The purpose of a biomaterial research is to serve in clinical applications to provide advanced materials, new methods, and techniques, while the selection of an animal model is a key aspect in the evaluation of implant materials. Although static magnetic fields (SMF) have no need for external equipment compared to alternating magnetic field, most experimental animal models involving SMF in the past have mainly chosen the femur or femoral condyles of rabbits [ 7 , 17 ], and they are rarely performed directly in the oral environment of large animals. In this study, a small magnetic rod was placed in the extended internal channel of the Ti implant ( Fig.…”

“…2 E). Such medium strength SMF has been found conducive to cell osteogenic differentiation [ 29 ] and to new bone reconstruction [ 7 , 30 ]. The micro-CT scanning images in Fig.…”

“…The ion exchange hydrothermal method was employed similar to the previous work [ 7 ]. The HYH particles (0.5 g in 20 mL of DI water) were mixed in Fe(NO 3 ) 3 solution (0.5 g, 20 mL), and hydrothermally treated at 160 °C for 6 h to facilitate Fe 3+ ions to exchange Ca 2+ ions on the surface region of the HYH particles.…”

“…In clinic, the new bone tissue usually takes approximately 3 months to form a stable osseointegration with implants [ 7 , 8 ]. It is necessary to accelerate the growth of new bone around the Ti implants and improve the osseointegration between Ti implants and new bone tissue.…”