Therapeutic-ion-doped bioactive glasses for vital pulp therapy: Linking glass chemistry, release dynamics, immunobiology, and clinical translation.

Vital pulp therapy (VPT) requires a material to control residual microbial challenge without sustaining injury in a confined, vascularized pulp, while preserving endogenous pulp cells, supporting angiogenesis, and enabling a continuous reparative dentin barrier and durable coronal seal. This critical narrative review asks under what composition-release-exposure conditions therapeutic ion-doped bioactive glasses (BGs) can provide antimicrobial and immune-regulatory effects while preserving pulp cell viability and supporting vascularized reparative dentin formation, and what minimum evidence is required before a formulation can be considered VPT-relevant. Silicate-, phosphate-, and borate/borosilicate-based glasses are compared because network-former and modifier content, processing route, particle size, porosity, and surface chemistry influence dissolution, pH, hydroxycarbonate apatite (HCA) formation, and co-release of Ca, Si, P, and therapeutic ions. Evidence is graded from clinical VPT and in vivo pulp-capping studies through pulp-specific in vitro models to indirect dental and non-dental mechanistic studies. Ag, Zn, Sr, Li, Ce, Ga, and selected emerging Cu- and Co-containing systems are evaluated using a common sequence: material identity and processing; measured release, pH, and interfacial precipitation; microbial and immune response; vascular and dental pulp cell response; and reparative dentin and formulation outcome. Cements, hydrogels, polymer/BG composites, and surface-functionalized systems are considered separately because handling, retention, sealing, and matrix-controlled transport alter exposure. The current evidence is predominantly preclinical and often lacks matched ion release, pH, co-ion, and biological measurements. No dopant can be selected on ion identity alone, and no universal safe concentration can be inferred across glass families or formulations. Clinical progression requires matched material and soluble-ion controls, measured release under biologically relevant conditions, disease-relevant pulp and immune models, formulation-specific handling and sealing tests, and direct safety and reparative-dentin outcomes.