Impact of cone system compatibility on single cone bioceramic obturation in canals prepared with variable taper NiTi rotary files.

Objective: This study examined how system-matching gutta-percha (GP) cones in conjunction with calcium silicate-based sealers (CSBS) affect the sealing quality of canals prepared with variable taper nickel titanium (NiTi) files, using confocal laser scanning microscopy (CLSM) and micro-computed tomography (micro-CT).

Materials And Methods: Forty-eight extracted human mandibular premolars were instrumented using the ProTaper Ultimate and divided into four groups based on GP cone (system-matching vs. non-matching) and sealer type (PlanB vs. TotalFill). Obturation was performed using the single-cone technique. Sealers were mixed with Fluo-3 dye for CLSM visualization. Micro-CT was used to quantify voids and gaps, while CLSM evaluated sealer penetration area and depth at the coronal, middle, and apical thirds.

Results: There were no significant differences in overall voids and gaps percentages between the cone systems (p = 0.66). System-matching cones however, significantly enhanced sealer penetration into dentinal tubules in terms of area, average, and maximum depth, especially in the apical third (p ≤ 0.001). PlanB demonstrated greater penetration area than TotalFill (p = 0.039).

Conclusion: The use of system-matching versus non-matching gutta-percha cones does not significantly affect the overall occurrence of voids and gaps in root canal fillings. However, system-matching cones improve sealer penetration into dentinal tubules, which differs among calcium silicate-based sealers. This emphasizes the importance of both cone fit and sealer selection in optimizing the quality of the single-cone obturation technique.

Clinical Relevance: In canals prepared with variable taper NiTi files, both the compatibility of gutta-percha cones and the properties of calcium silicate-based sealers play a key role in enhancing the quality of the single-cone obturation technique.