Konjac glucomannan (KGM) is a naturally derived polysaccharide known for its biocompatibility and gel-forming ability and has gained increasing attention in biomaterial and drug delivery research. However, the rheological behavior of KGM gels at clinically relevant concentrations for periodontal use has not been thoroughly investigated. In this study, KGM gels at 0.8%, 1.0%, and 1.2% (w/v) were prepared and evaluated using oscillatory and steady shear rheology. Rheological analysis revealed increased viscoelastic strength with increasing polymer content, with the 1.2% formulation showing the highest storage modulus, viscosity, and shear stress values across strain, frequency, and temperature ranges. All formulations demonstrated pronounced shear-thinning behavior and dominant elastic characteristics (G′ > G″), indicating stable gel network formation and favorable injectability. The viscoelastic profile remained stable near physiological temperature (37 °C), implying that the gel network can preserve mechanical integrity under intraoral conditions. Gamma irradiation at 15 kGy effectively achieved sterility without visible macroscopic instability, although a qualitative reduction in viscosity was observed. Collectively, these findings indicate that increasing KGM concentration improves mechanical robustness and viscoelastic stability, with the 1.2% gel demonstrating the most favorable rheological profile for potential localized periodontal application. © 2026 by the authors.