Objective To establish a stable mandibular fracture model with inferior alveolar nerve（IAN） mutilated for exploring the IAN influence to the expression of collagen Ⅰ during mandibular fracture. Methods Japanese white rabbits were selected and IAN was liberated. The right was leaven as it is and the left was cut off, then 2 mm×5 mm fracture model was made, and HE staining and chromotropic acid 2R-bright green staining and in situ hybridization of collagen Ⅰ mRNA were made to detect mandibular fracture healing and collagen Ⅰ mRNA expression. Results Fracture healing was smooth in IAN conserved side, but delayed in the IAN mutilated side. Collagen Ⅰ in situ hybridization showed that at one week and two weeks after surgery there were obvious differences between the two sides（P0.05）. Conclusion The IAN could regulate mandibular fracture healing, and influence collagen Ⅰ mRNA earlier expression.
