Study Of Bone Tissue Repair After Curettage Of Mandibular Cyst With CBCT

Objective:Cone beam computed tomography(CBCT)was used to measure the change of volume and gray value of the bone cavity after scraping the jaw cyst.The effects of bone cavity size,age,gender,and location of the bone cavity on postoperative osteogenesis were investigated.To investigate the outcome of bone defect after curettage of jaw cysts and to understand the quality and quantity of bone cavity osteogenesis after jaw cyst surgery.It is necessary to fill bone material in the same period and whether it can be implanted after surgery repair provides the basis.Methods:Twenty-seven patients who had undergone curettage of the jaw cyst were selected and divided into group A : maximum diameter ? 1.5cm,group B: 1.5cm <maximum diameter? 4cm,group C: maximum diameter> 4cm according to the size of the longest cyst diameter;Grouped by gender: male group,female group;grouped by patient's age: group a:age ? 30 years,group b: 30 years old <age ? 55 years old,group c: age> 55 years old;and cystic Anatomical groups were grouped: the mandibular body group and the mandibular angle group.The CBCT imaging data of immediate postoperative,6 months,and 12 months after operation were observed and measured.The maximum diameters in the sagittal,coronal,and axial positions were recorded(X,Y,respectively).Z)If the cyst shape is approximately circular,note the diameter as R.Apply the formula V=4/3?R3 or V=4/3?abc to calculate the cyst volume.The 3D model of the mandible in different periods of the patient was printed out,and the value of the bone cavity volume measured by the formula calculation method and the intra-model water injection method was statistically analyzed to see if the two methods were consistent and to evaluate the feasibility of the formula method.The gray value of the cyst was measured immediately after operation,6 months after operation,and 12 months after operation.Statistical data was analyzed using SPSS 17.0 software.Evaluate the condition of bone cavity repair at different postoperative days and reduce the residual bone cavity.Results:The computational analysis of postoperative CBCT showed that: 1.The rate of bone formation at 6 months after surgery in group A,B,and C were(59.86±7.10)%,(57.33±4.58)%,and(50.63±3.16)%,respectively,P<0.01,the difference was statistically significant.The rate of bone formation at 12 months after operation was(91.71 ± 5.91)%,(86.50 ±2.68)%,and(79.38 ± 1.69)% respectively,P<0.01,and the difference was statistically significant.2.In the gender group,the bone formation rate of males and females at 6 months after operation was(55.95±5.70)% and(56.13±7.32)% respectively,P>0.05,the difference was not statistically significant;male and female The bone formation rate at 12 months after operation was(85.58±5.77)% and(86.13±6.42)%,respectively,P>0.05,and the differencewas not statistically significant.3.Age group: The bone formation rate of a,b and c groups at 6 months after operation were(60.75±4.77)%,(57.78±5.33)%,(50.60±2.84)%,P<0.01.The difference was statistically significant;the bone formation rate of a,b,and c groups at12 months after operation was(88.75 ± 5.39)%,(87.44 ± 6.56)%,(81.80 ± 3.12)%,respectively.0.05,the difference was statistically significant.In the dissection group,the proportion of osteoblasts at the mandibular angle and mandibular body at 6 months after operation were(56.52 ± 5.98)% and(54.17 ± 6.62)%,respectively,P>0.05,and the difference was not statistically significant.Significance: The osteogenic proportions of the mandibular body and mandibular angle at 12 months after operation were:(86.05±5.84)%,(84.67±6.31)%,P>0.05,and the difference was not statistically significant.Conclusion:The CBCT images showed that the bone around the cysts was regenerated and the cavity was gradually reduced.The size of the original cyst was different,but the osteogenic rate was different,but it remained at 50% and 80% after 6 months and 12 months after operation.The three groups were 6 months and 12 months after operation.The osteogenic rate showed statistical differences.The cyst cavity with the shortest diameter less than 1.5cm in the primary cyst was completely healed 12 months after operation.In terms of bone mineral density,the bone healing index of small and medium-sized jaw cysts was maintained at approximately 80%.Some of the small-sized jaw cysts were even closer to 90%,indicating better bone healing.This indicates that small and medium-sized jaw cysts(With a maximum diameter of ?4cm,better spontaneous bone regeneration can be achieved without the use of exogenous bone graft material.However,the bone healing index of large maxillary cysts larger than 4cm was only about 60%,and the healing rate was poor.This indicated that for large jaw cysts(maximum diameter >4cm),exogenous bone graft material was implanted during the same period of operation.It may be of great help to increase bone mineral density after surgery.In this study,gender had little effect on postoperative bone repair,and no statistical difference was seen after surgery.The effect of age on postoperative bone repair showed a difference at 6 and 12 months after surgery.The older the age,the worse the bone formation in the bone cavity during the observation period.There were no significant differences in the healing of cysts at different sites.