Aims and background: This study aims to compare the fracture resistance force (FRF) and failure types of three-dimensional (3D)-printed stainless steel crowns (SSCs) and preformed SSCs in primary molars. Materials and methods: Forty-eight over-retained and extracted mandibular second deciduous molars were divided into two groups: one receiving 3D-printed crowns and the other preformed crowns. Fracture resistance testing was performed using a universal mechanical testing machine, and failure types were analyzed post-testing. Results: Fracture resistance testing revealed a significant difference between 3D-printed and preformed SSCs (p < 0.05), with 3D-printed crowns exhibiting a mean FRF of 3953.82 N compared to 742.94 N for preformed crowns. Additionally, Mann–Whitney U tests and Chi-squared tests were utilized to examine variations within and across the groups. Analysis of shear bond strength showed that 3D-printed crowns demonstrated superior adhesive performance compared to preformed crowns, with mean shear bond strength values of 3953.82 N and 742.94 N, respectively. Both groups A and B showed unrepairable failure modes. Conclusion: The study concludes that 3D-printed SSCs offer distinct advantages over preformed options, including tailored fit, enhanced mechanical properties, and improved longevity. These findings underscore the potential of 3D printing technology to revolutionize pediatric dental restoration practices. Clinical significance: Integrating 3D printing into pediatric dental practice holds promise for optimizing treatment outcomes and improving long-term oral health in children. The superior fracture resistance and adhesive performance of 3D-printed crowns suggest their potential to enhance restoration viability and reduce the need for subsequent interventions.