Abstract
Root canal treatment for primary teeth is a critical therapy aimed at eliminating infected tissue, relieving pain, and preserving the primary tooth until its natural exfoliation and replacement. The success of this treatment largely depends on the choice of root canal filling materials. In recent years, driven by advances in materials science and biomedicine, research on primary-tooth root canal filling materials has made substantial progress, including optimization of traditional materials such as zinc oxide-eugenol (ZOE) and calcium hydroxide-iodoform mixtures, as well as the development and increasing clinical adoption of novel materials such as calcium silicate bioceramics and bioactive glass. Currently used clinical materials show distinct characteristics: ZOE exhibits strong antibacterial activity but slow resorption; calcium hydroxide materials demonstrate favorable biocompatibility but overly rapid resorption; iodoform-based materials present relatively high short-term clinical success, though supporting evidence is mainly derived from short-term follow-up; calcium silicate bioceramics possess good bioactivity but weaker antibacterial effects; and antibiotic-based materials are applicable in non-instrumental treatment but carry risks including resistance, discoloration, and tooth staining. Clinical selection requires integrated consideration of material performance, tooth condition, child cooperation, treatment cost, and economic burden. Summarizing the antibacterial properties, biocompatibility, and recent clinical research progress of primary-tooth canal filling materials, and outlining their future development directions based on emerging material-design concepts (such as antibacterial-osteogenic dual-functional microspheres, injectable bioceramics, and light-responsive nanozyme systems), may provide references for pediatric dental clinical practice and new material research and development.