Advancements in GelMA/ceramic composites for dental applications: integration with portable 4D bioprinting technologies.

Recent advancements in biofabrication have positioned gelatin methacrylate (GelMA)/ceramic composites combined with portable 4D bioprinting as a groundbreaking approach for next-generation dental therapies. GelMA hydrogels, functionalized with ceramic nanoparticles such as hydroxyapatite, zirconia, and bioactive glass, exhibit superior mechanical properties, enhanced bioactivity, and improved osseointegration capabilities compared to conventional hydrogels. These composites uniquely combine GelMA's favorable biological properties (including cell-adhesive RGD motifs and tunable photocrosslinking) with the structural stability and bioactivity of ceramic fillers. When integrated with portable bioprinters, these materials enable precise, chairside fabrication of dynamic, patient-specific constructs capable of adapting to the oral environment's complex biomechanical demands. This review systematically examines the material science behind GelMA/ceramic composites, focusing on how ceramic incorporation enhances printability, mechanical strength, and biological performance; the design and operation of portable bioprinters for dental applications; and their combined potential in addressing clinical challenges such as periodontal tissue regeneration, dentin-pulp complex repair, and customized implant fabrication. We highlight recent breakthroughs, including stimuli-responsive scaffolds for guided tissue regeneration and in situ bioprinting techniques for pulp revascularization. The discussion extends to current limitations in material-bioprinter compatibility, sterilization challenges, and regulatory pathways while outlining future directions toward clinical translation.