Establishment Of Animal Model Of Chronic Periodontitis Combined With Vascular Calcification

Objective:Vascular calcification is a common pathological process which exists in the hypertension, atherosclerosis, diabetes, kidney disease, vascular lesions and blood vessel damage aging, which is one of the main risks factors of cardiovascular disease (CVD). Research suggests that vascular calcification is one special performance of the tissue calcification under the chronic inflammation stimulus. And the periodontitis is a world widely popular chronic non-specific infectious disease, which is one of the main risk factors of cardiovascular disease, diabetes and respiratory diseases. There is not any report about the relationship between periodontitis and vascular calcification up to now. Therefore, this experiment is desired to establish a compound model of chronic periodontitis and vascular calcification, so as to further explore the relationship between the periodontitis and vascular calcification.Methods:twenty male Wistar rats were divided into two groups randomly, vascular calcification with periodontitis group (group VDN+CP) and control group (group C). The periodontal treatment of VDN+CP group was silk ligature and inoculated with oral mixed bacteria; concurrently handling with vitamin D3(300kIU·kg-1,im) plus nicotine(25mg·kg-1,5ml·kg-1,po); C group, given amount of saline intramuscular injection, pure peanut oil to fill the stomach to replace vitamin D3and nicotine treatment respectively, meanwhile, inoculating of saline in the mouth. Animals were sacrificed after8weeks, and the following items were observed:(1) periodontal probing depth (PD) and gingival sulcular bleeding index (SBI).(2)Taking out and weighing the heart after dissection the rats, and measuring the whole heart weight(HW), HW/body weight (HW/BW).(3) Histological examination:Vascular tissue and periodontal tissue were taken and prepared for paraffin section.(4) Maxillary including molars were sectioned and scanned by Cone beam CT (CBCT).(5) Calcium content of vascular tissue was assayed. The collected data was statistically analyzed using variance test with the SPSS10.0statistics software.Results:The periodontal examination revealed:probing depth and gingival sulcular bleeding index of VDN+CP group were higher than those of the C group, and the differences were statistically significant (P<0.05).Cone beam CT scanning revealed:The alveolar bone resorption of the VDN+CP group had obvious difference compared to the C group. The pathological observe revealed:the vascular calcification lesions of aorta pectoralis and aorta abdominalis were formed in VDN+CP group.The VDN+CP group also exhibited significant increase of HW/BW and calcium content (P<0.05).Conclusion:The compound animals model of chronic periodontitis and vascular calcification was successfully established by vitamin D3(300kIU·kg-1，im) plus nicotine(25mg·kg-1,5ml·kg-1,po) and silk ligature and inoculated with oral mixed bacteria.