Objective To investigate the clinical application value of novel light-cured TheraCal LC pulp capping agent in children receiving deciduous teeth pulpotomy. Methods A retrospective study was performed on clinical data of 90 children who underwent deciduous teeth pulpotomy from August 2023 to May 2025. Subjects were divided according to different capping materials: 45 cases using TheraCal LC as study group, another 45 cases treated with iRoot BP Plus as control group. The treatment success rate, pain score, masticatory efficiency, gingival crevicular fluid inflammatory factors [interleukin-6 (IL-6), matrix metalloproteinase-3 (MMP-3)], root resorption, dentin bridge formation and adverse reactions were compared between two groups. Results There was no significant difference was found in treatment success rate at 12 months after operation between groups (P>0.05). At postoperative 3 months, the study group had lower pain score and higher masticatory efficiency than the control group (P<0.05), whereas no intergroup differences were observed at 6 and 12 months (P>0.05). The levels of gingival crevicular fluid IL-6 and MMP-3 in study group were significantly lower at 3, 6 and 12 months postoperatively (P<0.05). There was no significant difference in root resorption degree and dentin bridge formation rate at postoperative 12 months (P>0.05). No pulp inflammation, tooth discoloration or secondary caries occurred in either group. Conclusion The novel light-cured TheraCal LC shows favorable overall efficacy and safety in deciduous teeth pulpotomy; it can effectively suppress early gingival inflammation, relieve early postoperative pain and improve early masticatory function.