Changes Of Periodontal Bone Mineral Density And Related Factors During Occlusal Elongation In Diabetic Mice After Tooth Extraction

Objective:To explore the difference of bone mineral density,osteoclast change and SPARC expression at the gene level during the process of tooth occlusion in mice,and to provide theoretical basis for the treatment of diabetic dentition defect patients.Methods:Eighty C57 BL/6J mice were randomly divided into an experimental group(50 mice)and a control group(30 mice).An experimental model was established by intraperitoneal injection of streptozotocin(STZ)in the experimental group mice.The mice were given intraperitoneal injection of the same amount of sodium citrate buffer.After the model was successfully established,the right upper jaw and three molars of the two groups of mice were removed and sacrificed on days 0,3,6,9,and 12,and the right mandible was taken.Micro-CT was used to measure the bone mineral density of the right mandible in the two groups of mice;The mandible extracted from each time period was routinely fixed,decalcified,dehydrated,waxed,embedded,sliced and trap-stained.The changes of osteoclasts in the right mandibular molars of the right mandibular molars were observed in the corresponding time;The expression of SPARC in the right mandible of the two groups was observed by RT-qPCR.The SPARC primers were specific by PCR.Amplification,calculation of amplification and processing of all data using SPSS 21.0statistical method.Results:Micro CT: Bone density results showed that the two groups of mice had bone density increased during the period of 0 to 12 days after removal of the right maxillary molar,and the diabetic mice had other observing time except 0 days.The bone mineral density was less than the control group(P < 0.05),which was statistically significant;Trap staining results showed that new bone formation was observed in the mandibular sections of the two groups within 0 to 12 days,but the diabetic group was unevenly stained,in the same The positive staining of right mandibular osteoclasts in the time-diabetes group was less than that in the control group;RT-qPCR results: in the 0 to12 days after removal of the maxillary molars in both groups,the SPARC in the right mandible increased with time,but increased.The amplitude of SPARC amplification in the mandibular group was larger than that in the control group(P < 0.05).Conclusions:1.In the diabetic group,after the right maxillary molar was removed,the bone density of the right mandible was smaller than that of the control group,and the Trap staining of the diabetic group was weaker than that of the control group.The number of osteoclasts in the diabetic group was less than that of the control group.Compared with the control group,the diabetic mice had weak bone remodeling ability,and the osteoporosis tendency was more obvious than the control group.2.SPARC increased the expression of mouse mandibular dentition during the extension movement,suggesting that SPARC plays a role in the process of tooth occlusion elongation,and the SPARC expression of diabetic mice is higher than that of the control group,and it was speculated that diabetes may promote the expression of SPARC.