Application Of Demineralized Dentin Matrix Combined With GBR In Mandibular Defect Repair

Objective:Compared with the repair effect of demineralized dentin matrix(DDM)on the repair of bone defect after mandibular odontogenic cystic curettage and the repair of bone defect after simple cystic curettage,CBCT was used as a test method to photograph all patients before and during surgery.The CBCT image data of the first,third and sixth months of the latter were used to measure the gray scale of the CBCT specific site of each patient to represent the bone mineral density(BMD)of the region.The DMD was used to evaluate the DMD to the mandibular odontogenic cyst.Bone defect repair effect.Methods:The Department of Oral and Maxillofacial Surgery,Second Hospital of Shanxi Medical University,collected from December 2017 to December 2018,diagnosed as a mandibular odontogenic cyst lesion in 20 patients(5cm> cyst maximum diameter >1.5cm),11 males,female In 9 cases,the average age distribution ranged from 18 to 42 years old.Divided into the experimental group(the mandibular odontogenic cyst after scaling,DDM + repair membrane covered bone defect)10 cases and the blank control group(mandibular odontogenic cyst surgery after repair of the membrane cover bone defect)10 cases.The CBCT of all patients before and after the first,third,and sixth months of surgery was taken,and the gray scale of the affected side and the corresponding healthy side was calculated,and then converted into the gray ratio of the ratio of the affected side.(1)The image gray scale ratio between the experimental group and the control groupbefore and 3 and 6 months after surgery was analyzed by independent sample t test.(2)The gray scale ratio of the images in the experimental group and the control group was analyzed by one-way variance(ANOVA).(3)Statistical analysis of the transverse,coronal,and sagittal gray scales before,3,and 6 months after surgery was performed using repeated variance measurements.Results:1,the general situationAll patients were followed up before and after operation.There was no immune rejection in the wound after operation.All patients healed well.There was no abnormality in the color and texture of the surrounding mucosa within 6 months after operation.2,image data observationIn the first month after operation,no obvious density of the material was observed in the coronal,sagittal,and transverse sections.It was still occupied by the high-density shadow formed by the bone graft material,and only appeared at the edge of the defect.A small amount of low-density shadows,the edge of the bone defect is slightly blurred compared with the preoperative.There is still a high-density shadow formed by unabsorbed DDM in the center of the defect;most of DDM has been decomposed and absorbed at the 6th month after operation,and the bone defect area is significantly reduced.It can be seen that the high-density shadow formed by the new trabecular bone is filled with the defect area.There is no significant difference between the coronal,sagittal and transverse positions of the corresponding healthy side.In the first month after operation,the blank control group showed no change from the preoperative defect.The high density shadow formed by the new trabecular bone was not found in the bone defect.Only the defect edge was slightly blurred,and the third month was in each axis.A high-density obstruction shadow formed by a small number of new bone trabeculae can be seen on the defect surface,and there is still a large area of??low-density shadow at the center,and the osteogenesis speed is slow.There was a significant change in the 6th month after operation compared with the 3rd month.A largenumber of high-density obstructive lesions were seen at the edge of the defect,but the obstruction was significantly different from the normal normal bone tissue,and there was still a low-density shadow in the defect center.The osteogenesis rate is slow and the defect repair time is more than 6 months.3,data statistics results(1)There was no significant difference in the three-variable cross-sectional,coronal,and sagittal images between the experimental group and the control group(P>0.05).In the sixth month,the three-variable experimental group of transverse,coronal and sagittal images was significantly higher than the control group,and the difference was statistically significant(P<0.01).(2)One-way analysis of variance of imaging data in the experimental group and the control group,the preoperative,postoperative 3 months,postoperative 6th month transverse,coronal,sagittal images were all improved,gray scale ratio The representative bone density increased,and the difference was statistically significant(P<0.05).The difference between the cross-sectional,coronal and sagittal imaging groups in the experimental group was significantly higher than that in the control group in the third and sixth months,suggesting that the bone composition of DDM was better than the blank control group.(3)After repeated measures analysis of variance,the cross-sectional,coronal,and sagittal gray scales of the experimental group were significantly different before and 3 months after surgery,and the difference was statistically significant.Conclusion:1.The effect of DDM combined with GBR technique in the repair of mandibular odontogenic cyst defect is better than that of bone defect after simple cystectomy.2.DDM is a kind of bone graft that can promote the repair of mandibular defects,the degradation rate is matched with the rate of new bone formation,and the biocompatibility is great.