Radiation cross-linked collagen scaffolds facilitate root coverage and keratinized gingival regeneration.

The study aimed to develop a radiation cross-linked collagen scaffold (RCS) and assess its potential for root coverage and keratinized gingival regeneration, addressing the prevalent issue of gingival recession and limitations of traditional treatments. RCS was prepared through electron beam irradiation and cross-linking followed by freeze-drying. Its properties were evaluated, including Fourier transform infrared analysis, swelling behavior, microscopic observation, porosity measurement, compression modulus and structural stability. In a rat gingival recession model with 96 rats divided into four groups, the root coverage index and gingival health indices were measured, and histological analyses were conducted. The cross-linked network structure of RCS provided excellent mechanical properties and stability. In the rat model, RCS effectively promoted gingival regeneration, with the RCS group achieving a root coverage index of 87.7 ± 2.7 %, which was 54.13 %, 42.83 % and 8.41 % higher than that of the sham operation group, non-crosslinked group and chemical crosslinked group respectively. Histological analysis showed that RCS promoted anti-inflammatory macrophage polarization, enhanced collagen deposition and gingival lamina propria fiber density and increased angiogenesis. Additionally, RCS exhibited good biosafety, as blood indices and organ coefficients remained normal. In conclusion, RCS effectively promotes gingival regeneration and is a promising keratinized gingiva substitute for gingival recession, offering a new option for oral tissue repair.