【作者】 张琦；

【导师】 范存晖；

【作者基本信息】 青岛大学 ， 口腔正畸学（专业学位）， 2021， 硕士

【摘要】 【目的】:通过测量分析不同浓度磷酸氢二钾溶液CBCT影像下的灰度值,验证CBCT用于骨密度测量的准确性及可行性。然后通过CBCT测量分析不同血尿酸水平的青年男性牙槽骨骨密度的差异,了解高尿酸血症（Hyperuricemia,HUA）对牙槽骨骨密度的影响,以期为该类患者的临床治疗提供理论参考。【方法】:配置9种不同浓度的K₂HPO₄溶液,测量每种溶液在CBCT影像下的灰度值,计算出溶液浓度与灰度值之间的线性拟合关系,判断CBCT测量牙槽骨骨密度的准确性及可行性。对2020年-2021年于青岛大学附属医院口腔正畸科及痛风专病门诊就诊的18-35岁男性患者的血尿酸（serum uric acid,SUA）水平进行筛查,最终选取27例未接受治疗的高尿酸血症患者作为HUA组及23例SUA水平正常的志愿者作为对照组。HUA组平均年龄24.52±4.43岁,对照组平均年龄24.61±3.38岁。所有受试者进一步分组。（1）根据SUA是否正常将HUA组分为痛风组和无症状HUA组;（2）根据受试者SUA浓度分为5组:A组（SUA<360μmol/L）9人、B组（SUA:360-420μmol/L）14人,C组（SUA:420-510μmol/L）9人、D组（SUA:510-590μmol/L）10人和E组（SUA≥590μmol/L）8人。将所有受试者进行CBCT扫描后分别测量各组患者17根分叉区松质骨;上颌切牙区、前磨牙区、磨牙区;下颌前磨牙区、磨牙区松质骨及皮质骨等16个区域的平均灰度值。SPSS统计软件分析数据,独立样本t检验比较HUA组及对照组两组间平均灰度值的差异,单因素方差分别比较分析痛风组、无症状HUA组和对照组三组之间,以及A、B、C、D、E五组之间平均灰度值的差异。【结果】:（1）K₂HPO₄溶液灰度值与浓度间的线性拟合关系:Y=101.33+1.6778x,R²=0.9933。（2）HUA组17根分叉区域松质骨及下颌磨牙区牙槽嵴顶下皮质骨骨密度均小于对照组,（P<0.01）;HUA组上颌前牙区松质骨骨密度小于对照组（P<0.05）。（3）痛风组17根分叉区松质骨骨密度小于对照组（P<0.05）;痛风组及无症状HUA组上颌前牙区松质骨及下颌磨牙区牙槽嵴顶下2-4mm皮质骨均小于对照组（P<0.05）。（4）17根分叉区松质骨骨密度E组小于A、B、C组,D组小于A组（P<0.05）,且17根分叉区呈现出随尿酸浓度升高,牙槽骨松质骨密度逐渐降低的趋势。下颌磨牙牙槽嵴顶下2-4mm皮质骨密度C、D组小于A组,D组小于B组（P<0.05）。【结论】:1.CBCT是一种可靠的测量牙槽骨骨密度的方法。2.高尿酸血症影响人体牙槽骨骨密度:HUA患者部分区域（17根分叉区松质骨、上颌前牙区松质骨及下颌磨牙区牙槽嵴顶至根方2-4mm处）的牙槽骨骨密度低于正常受试者,尿酸盐晶体会破坏牙槽骨,导致骨密度降低。3.在17根分叉区域随着尿酸水平逐渐升高,牙槽骨松质骨密度有逐渐降低的趋势。更多还原

【Abstract】 [Objective]:The purpose of this experiment is to verify the accuracy and feasibility of CBCT for bone mineral density measurement by measuring and analyzing the grayscale values of dipotassium hydrogen phosphate solution with different concentrations under CBCT image.Then,CBCT was used to measure and analyze the difference of alveolar bone mineral density among young men with different blood uric acid levels,so as to understand the influence of Hyperuricemia（HUA）on alveolar bone mineral density,in order to provide theoretical reference for the clinical treatment of such patients.[Methods]:Nine different concentrations of K₂HPO₄ solutions were configured,and the gray value of each solution under CBCT image was measured.The linear fitting relationship between the solution concentration and gray value was calculated to judge the accuracy and feasibility of CBCT in measuring alveolar bone mineral density.The serum uric acid（SUA）levels of male patients aged 18 to 35 years old who were admitted to the Department of Orthodontics and the gout clinic of the Affiliated Hospital of Qingdao University from 2020to 2021 were screened.Finally,27 untreated hyperuricemia patients were selected as the HUA group and 23 volunteers with normal SUA levels as the control group.The mean age of HUA group was 24.52±4.43 years old,and that of control group was 24.61±3.38 years old.All subjects were further grouped.（1）According to whether SUA is normal,HUA group was divided into gout group and asymptomatic HUA group;（2）According to the concentration of SUA,the subjects were divided into 5 groups:group A（SUA<360μmol/L）with 9 subjects,group B（SUA:360-420μmol/L）with 14 subjects,group C（SUA:420-510μmol/L）with 9subjects,and group D（SUA:420-510μmol/L）with 14 subjects.Group E（SUA≥590μmol/L）and group E（SUA≥590μmol/L）.All subjects underwent CBCT scan and 17 cancellous bones in each group were measured respectively.Maxillary incisor area,premolar area,molar area;The average gray values of mandibular premolar area,molar area cancellous bone and cortical bone in 16 areas.SPSS statistical software analyzed the data,and independent sample t-test was used to compare the differences in average gray values between the HUA group and the control group.Single factor variance was used to compare and analyze the differences in average gray values between the gout group,the asymptomatic HUA group and the control group,as well as between the A,B,C,D and E groups.[Results]:（1）The linear fitting relationship between the gray value and concentration of K₂HPO₄ solution was Y=101.33+1.6778x,R²=0.9933.（2）The bone mineral density of 17cancellous bones in the bifurcation region and subalveolar crest cortical bone in the mandibular molar region in HUA group was lower than that in control group（P<0.01）;The bone density of cancellous bone in maxillary anterior area of HUA group was lower than that of control group（P<0.05）.（3）The bone mineral density of 17 bifurcated cancellous bones in gout group was lower than that in control group（P<0.05）.The cancellous bone in the maxillary anterior area and the cortical bone 2-4mm below the alveolar crest in the mandibular molar area in the gout group and asymptomatic HUA group were less than those in the control group（P<0.05）.（4）The bone mineral density in 17 bifurcation regions of cancellous bone in group E was lower than that in groups A,B and C,and that in group D was lower than that in group A（P<0.05）.The bone mineral density in 17 bifurcation regions of alveolar bone gradually decreased with the increase of uric acid concentration.The cortical bone mineral density of 2-4mm below alveolar crest of mandibular molars in groups C and D was lower than that in group A,and that in group D was lower than that in group B（P<0.05）.[Conclusion]:1.CBCT is a reliable method to measure the bone density of alveolar bone.2.Hyperuricemia affects human alveolar bone mineral density:The alveolar bone mineral density of HUA patients is lower than that of normal subjects in some areas（17 cancellous bones in the bifurcated region,cancellous bones in the maxillary anterior region,and alveolar ridge top to the root square 2-4mm）,and urate crystals will destroy alveolar bone,leading to decreased bone mineral density.3.The cancellous bone density of alveolar bone had a tendency to decrease gradually with the gradual increase of uric acid level in the 17 bifurcation areas.更多还原