万古霉素和妥布霉素局部给药对大鼠下颌骨再生的影响

Effect of local administration of vancomycin and tobramycin on mandibular regeneration in rats

目的建立大鼠颌骨缺损模型,观察局部应用万古霉素和妥布霉素粉剂对体内骨再生的影响。方法按照随机数字表法将24只SD雄性大鼠分为4组,每组各6只。对照组无需给予抗生素,万古霉素组给予万古霉素88μg/g,妥布霉素组给予妥布霉素176μg/g,联合组给予万古霉素88μg/g和妥布霉素176μg/g。每只大鼠制作5 mm全厚度标准颌骨缺损模型,并分别在骨缺损处放置抗生素粉末。术后12周收集标本,通过微型计算机断层扫描(micro-CT)分析缺损区骨体积/总骨体积比(BV/TV)、骨形成面积(BFA)和骨体积(BV)。再通过苏木精和伊红(HE)染色和马松染色进行组织学评估,分析骨再生情况。结果全部实验动物均无死亡,无万古霉素或妥布霉素相关毒性症状出现,伤口均愈合良好,无手术并发症及伤口感染。从micro-CT扫描分析,万古霉素组缺损区BV/TV、BFA、BV分别为(8.59±2.23)%、(10.33±2.01)%、(1.73±0.35)mm^(3),均小于对照组[(21.67±3.51)%、(27.55±2.60)%、(3.53±0.35)mm^(3)],而妥布霉素组BV/TV、BFA、BV分别为(45.03±3.20)%、(48.88±4.07)%、(9.06±0.56)mm^(3),均大于对照组,联合组缺损区BV/TV、BFA、BV分别为(22.67±4.04)%、(27.64±3.44)%、(3.41±0.33)mm^(3),均大于万古霉素组,差异均有统计学意义(P<0.05);对照组与联合组比较,差异均无统计学意义(P>0.05)。HE染色和马松染色支持micro-CT的扫描结果。万古霉素组的大鼠的每视野区成骨细胞数、骨组织百分比分别为(1.67±1.21)个、(3.83±1.47)%,均小于对照组[(6.33±1.03)个、(11.67±2.16)%],而妥布霉素组大鼠的每视野区成骨细胞数、骨组织百分比分别为(11.17±1.47)个、(29.50±2.81)%,均大于对照组,联合组大鼠的每视野区成骨细胞数、骨组织百分比分别为(6.33±0.82)个、(9.83±2.32)%,均大于万古霉素组,差异均有统计学意义(P<0.05);对照组与联合组比较,差异均无统计学意义(P>0.05)。结论对于骨缺损,推荐局部应用万古霉素联合妥布霉素,而非单用万古霉素。局部万古霉素给药可减少骨缺损区骨生成,而妥布霉素能促进骨再生。

Objective A mandibular defect rat model was established to investigate the osteogenic effect of local delivery vancomycin and tobramycin powder on bone regeneration.Methods A total of 24 SD male rats were divided into 4 groups according to the random number table method,with 6 rats in each group.The control group did not require antibiotics,while the vancomycin group received vancomycin 88 μg/g,tobramycin group administered tobramycin 176 μg/g,combined group administered with vancomycin 88 μg/g and tobramycin 176 μg/g.A 5 mm full-thickness standardized mandibular bone defect was performed with a drill in each rat and different antibiotic powders were placed over the bone defect space,respectively.All these animals were sacrificed after 12 weeks post-operation.The mandible bones were harvested for further radiographic and histologic analysis.The bone volume/total volume(BV/TV) ratio,bone volume(BV),and bone fractional area(BFA) in the defect area via micro-computed tomography(micro-CT scanning) were further analyzed.Then,the histology of rats was evaluated using hematoxylin and eosin(HE) staining and Masson staining,and the number of osteoblasts per filed was also analysed.Results There were no postoperative deaths,signs of vancomycin-related or tobramycin-related toxicity,or signs of systemic illness in any of the four groups.All wounds were healed well,and no complications or surgical site infection were observed in all rats.From the micro CT scanning analysis,the BV/TV,BFA,and BV in the defect area of the vancomycin group were(8.59±2.23)%,(10.33±2.01)%,and(1.73±0.35) mm^(3),respectively,which were smaller than those in the control group [21.67±3.51)%,(27.55±2.60)%,and(3.53±0.35) mm^(3)],while the BV/TV,BFA,and BV in the tobramycin group were(45.03±3.20)%,(48.88±4.07)%,and(9.06±0.56) mm^(3),respectively,which were larger than those in the control group,the BV/TV,BFA,and BV in the defect area of the combination group were(22.67±3.20)%,(27.64±3.44)%,and(3.41±0.33) mm^(3),which were higher than those in the vancomycin group,and the differences were statistically significant(P<0.05);there was no statistically significant difference between the control group and the combination group(P>0.05).HE staining,and Masson staining supported the scanning results of micro-CT.The number of osteoblasts and bone tissue percentage in each field of view of rats in the vancomycin group were 1.67±1.21 and(3.83±1.47)%,respectively,which were lower than those in the control group [6.33±1.03 and(11.67±2.16)%],while the number of osteoblasts and bone tissue percentage in each field of view of rats in the tobramycin group were 11.17±1.47 and(29.50±2.81)%,respectively,which were higher than those in the control group,the number of osteoblasts in each field of view of rats in the combination group was higher than that in the control group,the number of osteoblasts and the percentage of bone tissue in each visual field of rats in the combined group were 6.33±0.82 and(9.83±2.32)%,respectively,which were higher than those in the vancomycin group,and the differences were statistically significant(P<0.05);there was no statistically significant difference between the control group and the combination group(P>0.05).Conclusion For bone defect,local application of vancomycin combined with tobramycin is recommended other than vancomycin alone.Local administration of vancomycin can reduce osteogenesis in bone defect areas,while tobramycin can promote bone regeneration.