ABSTRACT
Objective To study the effect of sensory nerve on mandibular fracture through detecting the expression of SP in mandibular callus after inferior alveolar nerve (IAN)section. Methods Thirty-two Chinese rabbits were divided into two groups. All rabbits suffered from a standardized fracture in the left mandibula, and half of them underwent IAN section. The callus were stained by hematoxylin and immunochemistry to observe the expression of SP in callus and fracture healing process. Results There were a larger quantity of fibrous callus formation, relatively immatured woven bone callus, lower proportion between immatured bone callus and new bone callus and less immunoreactive substance P in the group with IAN section than in the group with intact IAN at day 7, 14, 21, 28 after operation. Strong immunoreaction of substance P occurred mainly in bone marrow on day 28 postoperatively in both groups. Conclusion Sensory nerve may involve in the process of callus formation at early stage and bone remodeling at late stage so that sensory nerve injury influences the quantity and quality of new callus formation. It seems that neural involvement in bone healing is related to the local concentration of SP in the callus.
ABSTRACT
Objective:To study the effect of sensory nerve on fracture of mandible and try to find the possible mechanism.Methods:Thirty-two China rabbits were used and divided into two groups for study.They all suffered from a standardized fracture in the left mandible,and half of them with inferior alveolar nerve section(IANS)or without.The callus were stained to observe the expression of substance P(SP)by immunochemistry and analysed by a computerized-graph analysing system.Results:Immunoreactivites of substance P occurred weakly on Day 7 and 14 after operation,and became stronger at late stage in IANS group.On the contrary,stronger immunoreactivites of substance P occurred at the early stage,less on day 21 posttrauma and stronger again on day 28 in control group.The strongest immunoreactivites at each stage occurred mainly in bone marrow on day 28 posttrauma in both groups.There was significant difference in the expressions of substance P in the callus between the two groups(P
