Anodized and hydrothermally treated titanium with a nanotopographic structure combined with dental pulp stem cells promotes bone formation in a rat calvarial bone defect model.

Purpose: Spark-discharged anodic oxidation coating on commercially pure titanium (SAc.p.Ti) has been shown to promote bone conduction and bone matrix mineralization during new bone formation. This study hypothesized that the combination of SAc.p.Ti with dental pulp stem cells (DPSCs) would enhance new bone formation. The objective was to evaluate the effect of this combination in a rat bone defect model.

Methods: DPSCs were isolated from Sprague-Dawley (SD) rat incisors and cultured. Calvarial bone defects were created in SD rats, followed by transplantation of commercially pure titanium (c.p.Ti), SAc.p.Ti, or SAc.p.Ti combined with DPSCs. Bone formation was assessed using micro-computed tomography (micro-CT). Toluidine blue O staining was employed to evaluate bone-implant contact and the newly formed bone area. Hematoxylin-eosin (HE) staining was performed to identify osteoblast-like cells.

Results: Micro-CT analysis revealed hard tissue formation on the surface of SAc.p.Ti. Toluidine blue O staining showed significantly greater bone-implant contact and newly formed bone area in the SAc.p.Ti/DPSC group compared to the c.p.Ti and SAc.p.Ti groups. HE staining confirmed the presence of osteoblast-like cells at the defect margins, with evidence of new bone formation on the surface of SAc.p.Ti and in the SAc.p.Ti/DPSC groups.

Conclusions: The combination of SAc.p.Ti and DPSCs presents a promising strategy for promoting new bone formation in rat calvarial defect model.