Coronal tubule penetration of different calcium silicate materials in regenerative endodontics: a comparative study with a novel imaging method

This study evaluated the coronal dentinal tubule penetration of three calcium silicate-based materials used in regenerative endodontic procedures. Sixty extracted human mandibular premolars were sectioned 5 mm from the apex and prepared with Peeso reamers to simulate immature apices. Regenerative procedures followed AAE guidelines. Before placement of calcium hydroxide, canals were irrigated with 20 mL 2.5% NaOCl for 5 min and 20 mL 17% EDTA for 5 min, respectively. The canals were sealed with Cavit and incubated for four weeks. In the second visit simulation, the temporary restoration was removed. After removal and irrigation with 17% EDTA, human blood was introduced 3–4 mm below the cemento-enamel junction, and a collagen matrix was placed over the clot. Samples were randomly divided into three groups (n = 20) and capped with Biodentine, Dia-Root Bio MTA, or Bio-C Repair, each mixed with 0.01% rhodamine B. After incubation at 37 °C and 100% humidity for two weeks, 2-mm coronal root sections were analyzed with the Cytation™ 5 Cell Imaging Multimode Reader. Dentinal tubule penetration was measured at four standardized points using ImageJ. Statistical analysis used the Shapiro-Wilk, ANOVA, and Duncan tests (p < 0.05). Biodentine and Bio-C Repair showed significantly greater maximum penetration depths than Dia-Root Bio MTA (p = 0.001). Bio-C Repair also exhibited the highest mean penetration depth, significantly higher than the other materials (p = 0.026). Bio-C Repair demonstrated superior coronal dentinal tubule penetration compared with Biodentine and Dia-Root Bio MTA. Bio-C Repair may be a reliable material for regenerative endodontic procedures requiring an effective coronal seal.