Comparison of intratubular biomineralization between in vivo and in vitro conditions

Purpose: This study aimed to investigate whether the amount, chemical characteristics, and morphological patterns of intratubular biomineralization are similar under both in vivo and in vitro conditions. Methods: Root canal treatment, which included preparation, irrigation, and obturation with gutta-percha plus a premixed hydraulic bioceramic endodontic sealer, was performed on seven teeth in seven patients. These teeth were then extracted between 6 months and 5 years later for reasons unrelated to the endodontic therapy. Seven extracted, single-rooted human teeth were also endodontically treated using the same procedure. The in vitro-treated teeth were stored in phosphate-buffered saline at room temperature for 30 days. Scanning electron microscopy was used to analyze the amount and morphology of intratubular biomineralization in all 14 teeth. Energy-dispersive X-ray spectroscopy was also performed to identify the elements present in the dentinal tubules. Results: There was no significant difference in the measured amount of biomineralization between the two groups. However, the morphological patterns of precipitates within the dentinal tubules differed between the in vivo (granular) and in vitro (plate-like) conditions. Conclusion: These results indicate that quantitative evaluation of the amount of biomineralization in vitro is a feasible alternative for replication of in vivo conditions.