PEEK in Fixed Dental Prostheses: Application and Adhesion Improvement

Polyetheretherketone (PEEK) has been widely applied in fixed dental prostheses, comprising crowns, fixed partial dentures, and post-and-core. PEEK’s excellent mechanical properties facilitate better stress distribution than conventional materials, protecting the abutment teeth. However, the stiffness of PEEK is not sufficient, which can be improved via fiber reinforcement. PEEK is biocompatible. It is nonmutagenic, noncytotoxic, and nonallergenic. However, the chemical stability of PEEK is a double-edged sword. On the one hand, PEEK is nondegradable and intraoral corrosion is minimized. On the other hand, the inert surface makes adhesive bonding difficult. Numerous strategies for improving the adhesive properties of PEEK have been explored, including acid etching, plasma treatment, airborne particle abrasion, laser treatment, and adhesive systems

Modulating Lineage Specification in Stem Cell Differentiation via Bioelectrical Stimulation Intensity Matching

Abstract Development and regeneration in biological tissues are fundamentally affected by stem‐cell‐fate commitment. Bioelectricity is heterogeneous between different tissues and crucially regulates cell behaviors, including cell differentiation. However, the effects of heterogeneous bioelectricity on stem‐cell differentiation remain poorly understood. Herein, it is shown that providing stem cells with electrical stimulation matching the endogenous membrane potentials of cells derived from different tissues (osteogenic‐related: −55.05 ± 4.22 mV, neurogenic‐related: −84.8 ± 7.48 mV) can induce their osteogenic or neurogenic lineage commitment. Molecular dynamics simulations indicated that the osteogenic‐related surface potential favors the adsorption of fibronectin, while the neurogenic‐related surface potential enhances the adsorption of FGF‐2. These different protein adsorptions trigger either downstream Wnt or Erk signaling, which direct stem‐cell differentiation. Surface‐potential‐mediated lineage‐specification of stem cells using bioelectrical intensity has enormous potential application value in tissue regenerative therapy

Mg‐CS/HA Microscaffolds Display Excellent Biodegradability and Controlled Release of Si and Mg Bioactive Ions to Synergistically Promote Vascularized Bone Regeneration

Abstract For bone defect repair, it is critical to utilize biomaterials with pro‐angiogenic properties to enhance osteogenesis. Hydroxyapatite (HA)‐based materials widely used in clinical applications have shown much potential for bone repair. However, their predominant calcium phosphate (CaP) composition and poor biodegradability limit their angiogenic potential and hence osteogenic efficiency of HA‐based materials. Here, a magnesium ion‐doped calcium silicate/HA composite microscaffold (Mg‐CS/HA) is fabricated to enhance angiogenesis and osteogenic efficiency for bone repair. Incorporation of CS improved the biodegradability of the Mg‐CS/HA microscaffold, which could simultaneously release Si and Mg bioactive ions during the early stage of implantation, synergistically enhancing angiogenesis and osteogenic efficiency. In co‐culture systems, the synergistic effects of Si and Mg ions promote the “osteogenesis‐angiogenesis coupling effect.” In vivo, the Mg‐CS/HA microscaffold could significantly promote reconstruction of the vascular network and bone regeneration. This study thus provides a new strategy for coordinated release of bioactive ions to achieve synergistic effects on vascularized bone regeneration by HA‐based bone implant materials