Pathological or traumatic loss of teeth often results in the resorption and remodeling of the affected alveoli in mammals. However, instances of alveolar remodeling in reptiles are rare. A remodeled alveolus in the ma...Pathological or traumatic loss of teeth often results in the resorption and remodeling of the affected alveoli in mammals. However, instances of alveolar remodeling in reptiles are rare. A remodeled alveolus in the maxilla of the Chinese theropod Sinosaurus (Lower Jurassic Lower Lufeng Formation) is the first confirmed example of such dental pathology in a dinosaur. Given the known relationship between feeding behavior and tooth damage in theropods (teeth with spalled enamel, tooth crowns embedded in bone) and the absence of dentary, maxillary, and premaxillary osteomyelitis, traumatic loss of a tooth is most likely the cause of alveolar remodeling. Based on the extent of remodeling, the injury and subsequent tooth loss were non-fatal in this individual.展开更多
目的:分析成人双颌前突患者治疗前后上颌切牙区唇腭侧牙槽骨的变化,为正畸治疗中在牙槽骨内的安全移动牙齿提供参考依据。方法:纳入23例成人双颌前突的患者,拔除4颗第一前磨牙,采用直丝弓矫治技术一步法整体内收上下前牙。患者治疗前后...目的:分析成人双颌前突患者治疗前后上颌切牙区唇腭侧牙槽骨的变化,为正畸治疗中在牙槽骨内的安全移动牙齿提供参考依据。方法:纳入23例成人双颌前突的患者,拔除4颗第一前磨牙,采用直丝弓矫治技术一步法整体内收上下前牙。患者治疗前后均拍摄锥体束CT片,测量上颌切牙区唇腭侧牙槽骨厚度(alveolar bone thickness,ABT)、釉牙骨质界-牙槽嵴顶的高度(alveolar bone height,ABH)和牙槽骨面积(alveolar bone area,ABA)。结果:治疗后上颌切牙区唇侧的ABT在根中和根尖部水平显著升高,而腭侧的ABT在颈部、根中和根尖3个水平上均下降(P<0.05);中切牙在颈部和根中两个水平上总ABT显著减少(P<0.05),而侧切牙在颈部、根中和根尖处总ABT均减少(P<0.05);正畸治疗后,切牙区腭侧ABA减少,而唇侧ABA增加(P<0.05);上颌中切牙和侧切牙腭侧的ABH和上颌侧切牙唇侧的ABH显著增加(P<0.01)。结论:正畸治疗会导致成人双颌前突患者的切牙区腭侧的牙槽骨发生显著吸收,减少整个切牙区的牙槽骨量,需关注其对牙周组织的长期影响。展开更多
目的·利用锥形束CT(cone-beam computed tomography,CBCT)比较上颌前牙倾斜性内收(retraction adjunct with tip,R&Tp)和控根性内收(retraction adjunct with torque,R&Tq)产生的牙槽骨改建反应差异。方法·选取40例...目的·利用锥形束CT(cone-beam computed tomography,CBCT)比较上颌前牙倾斜性内收(retraction adjunct with tip,R&Tp)和控根性内收(retraction adjunct with torque,R&Tq)产生的牙槽骨改建反应差异。方法·选取40例符合纳入标准的安氏Ⅱ类1分类青少年患者,根据牙齿实际内收方式对纳入对象所有160颗上颌切牙进行标准化分组(分为倾斜内收组和控根内收组),利用CBCT影像结合三维测量软件对2组牙齿内收情况以及相关牙槽骨高度和厚度变化进行测量分析和比较。结果·2组前牙均实现较大范围内收和直立,倾斜内收组牙冠内收距离及内收角度均明显大于控根内收组(均P=0.000)。倾斜内收组L3、P1厚度显著减小(均P=0.000),控根内收组P1、P2厚度显著减小(均P=0.000)。倾斜内收组T1厚度减小(P=0.000),控根内收组各水平牙槽骨总厚度均减小(均P=0.000)。2组唇侧(P=0.000)、腭侧(P=0.000)牙槽嵴高度均下降,且腭侧牙槽嵴高度降低更显著。结论·安氏Ⅱ类1分类青少年患者上颌前牙在较大范围内收时,倾斜内收组唇侧根尖区、腭侧牙槽嵴区以及控根内收组腭侧牙根颈部及中部区域均为牙槽骨吸收高风险区。展开更多
文摘Pathological or traumatic loss of teeth often results in the resorption and remodeling of the affected alveoli in mammals. However, instances of alveolar remodeling in reptiles are rare. A remodeled alveolus in the maxilla of the Chinese theropod Sinosaurus (Lower Jurassic Lower Lufeng Formation) is the first confirmed example of such dental pathology in a dinosaur. Given the known relationship between feeding behavior and tooth damage in theropods (teeth with spalled enamel, tooth crowns embedded in bone) and the absence of dentary, maxillary, and premaxillary osteomyelitis, traumatic loss of a tooth is most likely the cause of alveolar remodeling. Based on the extent of remodeling, the injury and subsequent tooth loss were non-fatal in this individual.
文摘目的:分析成人双颌前突患者治疗前后上颌切牙区唇腭侧牙槽骨的变化,为正畸治疗中在牙槽骨内的安全移动牙齿提供参考依据。方法:纳入23例成人双颌前突的患者,拔除4颗第一前磨牙,采用直丝弓矫治技术一步法整体内收上下前牙。患者治疗前后均拍摄锥体束CT片,测量上颌切牙区唇腭侧牙槽骨厚度(alveolar bone thickness,ABT)、釉牙骨质界-牙槽嵴顶的高度(alveolar bone height,ABH)和牙槽骨面积(alveolar bone area,ABA)。结果:治疗后上颌切牙区唇侧的ABT在根中和根尖部水平显著升高,而腭侧的ABT在颈部、根中和根尖3个水平上均下降(P<0.05);中切牙在颈部和根中两个水平上总ABT显著减少(P<0.05),而侧切牙在颈部、根中和根尖处总ABT均减少(P<0.05);正畸治疗后,切牙区腭侧ABA减少,而唇侧ABA增加(P<0.05);上颌中切牙和侧切牙腭侧的ABH和上颌侧切牙唇侧的ABH显著增加(P<0.01)。结论:正畸治疗会导致成人双颌前突患者的切牙区腭侧的牙槽骨发生显著吸收,减少整个切牙区的牙槽骨量,需关注其对牙周组织的长期影响。
文摘目的·利用锥形束CT(cone-beam computed tomography,CBCT)比较上颌前牙倾斜性内收(retraction adjunct with tip,R&Tp)和控根性内收(retraction adjunct with torque,R&Tq)产生的牙槽骨改建反应差异。方法·选取40例符合纳入标准的安氏Ⅱ类1分类青少年患者,根据牙齿实际内收方式对纳入对象所有160颗上颌切牙进行标准化分组(分为倾斜内收组和控根内收组),利用CBCT影像结合三维测量软件对2组牙齿内收情况以及相关牙槽骨高度和厚度变化进行测量分析和比较。结果·2组前牙均实现较大范围内收和直立,倾斜内收组牙冠内收距离及内收角度均明显大于控根内收组(均P=0.000)。倾斜内收组L3、P1厚度显著减小(均P=0.000),控根内收组P1、P2厚度显著减小(均P=0.000)。倾斜内收组T1厚度减小(P=0.000),控根内收组各水平牙槽骨总厚度均减小(均P=0.000)。2组唇侧(P=0.000)、腭侧(P=0.000)牙槽嵴高度均下降,且腭侧牙槽嵴高度降低更显著。结论·安氏Ⅱ类1分类青少年患者上颌前牙在较大范围内收时,倾斜内收组唇侧根尖区、腭侧牙槽嵴区以及控根内收组腭侧牙根颈部及中部区域均为牙槽骨吸收高风险区。
