Biomechanical Analysis of Post–Core Crown Restoration in Dog Maxillary Canine Teeth

Post–core restoration serves as an effective treatment for fractured canine teeth. However, the influence of post length on the stability of the teeth for small animals remains controversial. This study employs finite element analysis and a force machine in vitro to evaluate the biomechanical effects of varying fiber post lengths in maxillary canine teeth, aiming to establish theoretical guidelines for optimizing post–core restoration in canine dentistry. Three-dimensional models of the canine teeth of large, medium, and small dogs (German Shepherds, Beagles, and Teddy dogs) were constructed using finite element analysis (FEA). Fiber posts with post-to-root length ratios of 1/3, 1/2, and 2/3 were established. Stress distribution (σ1/σ2) and total deformation under 100–1100 N loading were analyzed virtually in ANSYS (version 17.0.0.19190), as well as in a force machine in vitro. FEA and in vitro fracture tests showed good correlation (p > 0.05). Fracture loads for large, medium, and small breeds were 1115.851 ± 6.984 N (distal) and 1177.39 ± 5.82 N (lingual), 901.627 ± 7.49 N (distal) and 976.504 ± 6.399 N (lingual), and 812.733 ± 5.476 N (distal) and 897.642 ± 6.42 N (lingual), respectively. The fiber post with a root–post ratio of 2/3 exhibited the highest fracture resistance, potentially making it be the best choice for post–core restoration.