Dose-Dependent Effects of Allantoin on Bone Regeneration in Mandibular Distraction Osteogenesis

Local allantoin administration enhances regenerative quantity and quality in rabbit mandibular DO in a dose-dependent manner, with 1.0 mg/kg providing the most favorable improvement in trabecular microarchitecture, matrix deposition, and osteogenic/CXCR4 signaling. Higher dosing (2.0 mg/kg) confers no additional benefit, suggesting a bell-shaped dose-response and underscoring the need for dose optimization before clinical translation.