儿童下颌骨骨密度的定量CT测量研究

目的 对71名10～16岁儿童的下颌骨骨密度进行定量CT(QCT)测量,探讨骨密度的变化情况.方法 对每名儿童的左侧下颌角、颏中部和右侧下颌角分别进行QCT扫描测量,并按照年龄和性别进行分析.结果 10～12岁儿童左侧下颌角、颏中部、右侧下颌角骨密度平均值分别为44.29、89.70、54.31 mg/dL;13～16岁儿童左侧下颌角、颏中部、右侧下颌角骨密度平均值分别为63.85、122.47、70.23 mg/dL.结论 男性儿童10～12岁组与13～16岁组下颌骨骨密度值随年龄的增加而明显增高,但左右两侧下颌角及颏中部骨密度值有较大差异,男女之间骨密度值也有很大的差异.     

儿童下颌骨骨密度的定量CT测量研究

目的对71名10～16岁儿童的下颌骨骨密度进行定量CT（QCT）测量，探讨骨密度的变化情况。方法对每名儿童的左侧下颌角、颏中部和右侧下颌角分别进行QCT扫描测量，并按照年龄和性别进行分析。结果10～12岁儿童左侧下颌角、颏中部、右侧下颌角骨密度平均值分别为44.29、89.70、54.31 mg/dL；13～16岁儿童左侧下颌角、颏中部、右侧下颌角骨密度平均值分别为63.85、122.47、70.23 mg/dL。结论男性儿童10～12岁组与13～16岁组下颌骨骨密度值随年龄的增加而明显增高，但左右两侧下颌角及颏中部骨密度值有较大差异，男女之间骨密度值也有很大的差异。     

成人骨性Ⅲ类错不同垂直骨面型下颌骨及颏部的比较

目的:比较成人骨性Ⅲ类错不同垂直骨面型下颌骨及颏部形态,探讨下颌平面角与下颌骨及颏部形态的相互关系。方法:选择年龄17～29岁、平均(21±3.020)岁的骨性Ⅲ类错[ANB<0°,平均为(-3.927±2.7637)°]患者60例(男、女各30例)为研究对象,根据下颌平面角(FH-MP)的大小将研究对象分为低角、均角及高角组3组,每组各20例(男、女各10例),分别测量其下颌骨及颏部骨性结构,使用SPSS16.0软件包进行统计学分析。结果:高角组的下颌角、颏高度和颏曲度大于平均角组和低角组(P<0.05);高角组的颏最小厚度、颏最小厚度/颏厚度比、颏厚度/颏高度比和颏角小于平均角组和低角组(P<0.05);进一步经两两比较,下颌角、颏最小厚度、颏最小厚度/颏厚度比、颏高度、颏厚度/颏高度比和颏角在低角组与高角组,平均角组与高角组间均有显著差异(P<0.05);而颏曲度在低角组与高角组有统计学差异(P<0.05)。下颌平面角的大小与下颌角、颏高度和颏曲度呈正相关(P<0.05),而与颏最小厚度、颏最小厚度/颏厚度比、颏厚度/颏高度比和颏角呈负相关(P<0.05)。结论:成人骨性Ⅲ类错不同垂直骨面型下颌骨及颏部形态不同,下颌平面角与下颌骨及颏部形态存在相关关系。     

老年性骨质疏松症患者下颌骨骨密度的检测分析

目的 研究老年性骨质疏松症患者下颌骨骨密度的改变,探讨下颌骨骨密度改变与全身骨密度改变的相关性.方法 对加例老年性骨质疏松症患者(A组)、40名非骨质疏松症老年志愿者(B组)和40名青年健康志愿者(C组)摄取标准化数字曲面体层X线片;应用计算机图像处理软件对标准化数字曲面体层X线片的下颌骨下缘皮质骨厚度、曲面体层下颌指数、牙槽骨骨密度、牙槽骨骨高度进行测量.使用双能X线吸收骨密度仪测量腰椎及髋关节骨密度.结果 A组下颌骨下缘皮质骨厚度(3.57±0.82)与全身骨密度显著相关(P＜0.05).A组与C组标准化数字曲面体层X线片测量指标(下颌骨下缘皮质骨厚度、曲面体层下颌指数、牙槽骨骨密度、牙槽骨骨高度)差异均具有统计学意义(P＜0.05);A组下颌骨下缘皮质骨厚度(3.57±0.82)与曲面体层下颌指数(0.29±0.06)与B组(下颌骨下缘皮质骨厚度:4.07±0.75,曲面体层下颌指数:0.32±0.07),差异有统计学意义(P＜0.05);B组牙槽骨骨密度(105.40±20.48)与牙槽骨骨高度(10.42±1.82)与C组(牙槽骨骨密度:117.10±22.23,牙槽骨骨高度:11.69±1.63)差异具有统计学意义(P＜0.05).结论 老年性骨质疏松症患者下颌骨下缘皮质骨丢失明显,骨质疏松症对健康牙槽骨没有显著影响,其牙槽骨骨丢失主要为一种增龄性改变.     

颏下岛状肌皮瓣血管的解剖与超声评价

目的探讨应用彩色多普勒超声检测颏下岛状肌皮瓣(submental musculocutaneous island flap),SMIF血管的显示价值,为SMIF的临床应用提供影像学信息。方法选取拟行SMIF移植的患者35例,术前应用彩色多普勒超声测量双侧颏下动脉起始处距离下颌骨下缘、下颌角及颏中点的距离;在超声下探测血管走行,同时行面前静脉、颌外动脉体表标记,并与术中所见血管解剖情况进行对比。结果 35例患者术前超声检测与术中所见符合率为100%;经超声探测出面前静脉的6种走行方式,颌外动脉的4种走行方式;测得左侧颏下动脉起始处距离下颌骨下缘的距离为(0.53±0.09)cm,距离下颌角的距离为(1.82±0.33)cm,距离颏中点的距离为(6.08±0.52)cm;右侧颏下动脉起始处距离下颌骨下缘的距离为(0.52±0.09)cm,距离下颌角的距离为(1.75±0.29)cm,距离颏中点的距离为(6.12±0.63)cm。结论彩色多普勒超声可以直观地显示SMIF血管的走行、分布及变异情况,从而为SMIF的制备提供影像学依据。     

颏管的应用解剖学研究

目的 :研究国人颏管的形态及颏管与下颌管、切牙神经管的位置关系 ,为口腔牙种植等颏区手术提供解剖学数据。方法 :磨开 13例 ( 2 6侧 )甲醛溶液固定的湿下颌骨标本的下颌管前段、颏管和切牙神经管始段 ,直接观察测量。另取 2 1侧经过脱钙处理的下颌骨标本 ,解剖并显露下颌管、颏管和切牙神经管进行观测。结果 :下颌管前端分成 2个管 :颏管和切牙神经管。大多数颏管行向后上外开口于颏孔 ,颏管长为 :( 5 .61±1.0 7)mm ,管径为 :( 2 .5 3± 0 .47)mm ,颏孔前缘至下颌管前端的水平距离为 :( 2 .82± 1.2 9)mm ,颏孔下缘到下颌管上缘的垂直距离为 ( 3 .83± 1.43 )mm ,颏管与下颌管之间的角度为 ( 63 .5 7± 13 .71)° ,颏管内有颏神经和颏血管行走。结论 :下颌管向后上外方续为颏管再通向颏孔 ,并非以往认为的下颌管自后上内向前下外方向直接开口于颏孔。     

人下颌骨枪弹伤有限元仿真及致伤生物力学变化研究

目的:建立人下颌骨三维有限元模型,动态仿真不同入射角度子弹侵彻下颌骨三维模型过程,探讨下颌骨枪弹伤的生物力学变化.方法:将中国数字化可视人体下颌骨数据通过Mimics软件进行三维实体重建,建立人下颌骨三维有限元模型,在LS-DYNA软件中模拟7.62 mm弹丸以不同入射角度致伤下颌骨过程,分析致伤过程中下颌骨生物力学参数变化.结果:(1)建立人下颌骨枪弹伤三维有限元模型,成功模拟不同入射角度7.62 mm弹丸下颌骨的致伤过程;(2)子弹以90°、67.5°入射下颌角时,下颌骨的最大应力位于非撞击侧的下颌角内侧面;而子弹以45°入射下颌角时,下颌骨的最大应力位于撞击侧的下颌角外侧面;(3)下颌骨损伤过程中应力主要集中在下颌角、下颌升支、颏部、髁突颈部,并依次减小.结论:有限元仿真可动态模拟人下颌骨弹丸致伤过程,人下颌骨枪弹伤的生物力学特点是压力波造成各部分应力改变会在下颌角、下颌升支、颏部、髁突颈部等薄弱区域集中,出现传导改变和传导中断,形成较强大的应力梯度.     

不同类型下颌骨骨折后患者上气道CBCT观察

目的:探讨不同类型下颌骨骨折对上气道间隙的影响。方法:选取不同类型下颌骨骨折患者56例(男29例,女27例),正常对照组20例(男12例,女8例)。将整个上气道分为腭咽段、舌咽段、喉咽段3个区,所有人在同一条件下进行上气道锥形束CT(CBCT)扫描,数据经DICOM格式直接转入Simplant软件中,测量上气道各段容积及气道总容积。结果:单、双侧下颌角线性骨折患者喉咽气道容积及气道总容积明显变小(P<0.05)。双侧下颌骨体部线性骨折及颏/颏旁粉碎性骨折对舌咽气道、喉咽气道容积及气道总容积影响显著,严重者易引发通气障碍。结论:三维重建测量技术,可直观显示双侧下颌骨体部线性骨折和颏/颏旁粉碎性骨折后,上气道间隙的减小,指导临床。     

双侧下颌骨肿块

1病例报告男,50岁,半年前发现下颌前部膨隆,有一黄豆大小肿块,逐渐增大。查体:下颌骨颏部可及一5cm×3cm膨隆,未及乒乓球样感,下前牙松动Ⅱ～Ⅲ度,双侧下颌下可触及多个肿大淋巴结,大小0．5～1．0cm不等,光滑,可活动,无压痛。全景片示左下颌第一磨牙至右下颌第二前磨牙之间骨密度减低影。无家族性疾病史。临床诊断为“下颌骨囊肿”。于局麻下行“下颌骨囊肿刮治术”。     

有牙颌与无牙颌老年人下颌及髋部骨密度的比较研究

目的　观察有牙颌与无牙颌老年人下颌骨及髋部骨骨密度有无差别 ,探讨影响牙槽骨骨吸收及无牙颌发生的全身危险因素。方法　采用双能X线吸收法测量全部研究对象的右侧髋部骨密度及左侧下颌角骨密度。结果　无牙颌与有牙颌老年人相比 ,前者下颌角骨密度较低 (P <0 0 0 1) ;髋部 (股骨颈、大粗隆、Ward三角区 )骨密度也表现出不同程度的降低。结论　髋部或全身骨密度减低、下颌骨骨密度减低是导致牙齿缺失及无牙颌的因素之一。     

Study of mandible bone mineral density of Chinese adults by dual-energy X-ray absorptiometry

The objective of this study was to measure the bone mineral density (BMD) of mandible and study the correlation between the BMD of the mandible and the lumbar vertebrae. 224 healthy volunteers were recruited in China and divided into 6 age groups: 20-29, 30-39, 40-49, 50-59, 60-69, and over 70 years. Dual-energy X-ray absorptiometry (DXA) was used to measure the BMD of the lumbar vertebrae and the mandible of each volunteer. The BMD of mandibular chin, mandibular angle and the lumbar vertebrae (L1-L4) was 1.3013 ± 0.2576 g/cm², 1.0484 ± 0.1087 g/cm² and 1.1195 ± 0.1373 g/cm², respectively. The BMD of mandibular angle and lumbar vertebrae decreased significantly beyond the age of 50 years. There was a significant difference between males and females in the BMD of the mandibular angle and lumbar vertebrae in the 50-59, 60-69 and over 70 year age groups. The authors found that the BMD of mandibular angles correlates with that of lumbar vertebrae. This study suggests that measurement of mandible BMD could be used to predict osteoporosis.     

口腔全景片评价更年期妇女骨质疏松的研究

目的 了解更年期妇女口腔数字全景片的相关颌骨骨密度(BMD)与全身BMD的关系.方法 选择100例更年期妇女,测定全身BMD相关指数,同时拍摄口腔数字全景片,测定其下颌骨相对BMD、曲面体层下颌指数(PMI)、下颌骨吸收指数(MRI),对其进行统计学相关性分析.结果 下颌骨相对BMD及PMI与全身BMD各指数均有相关性;MRI与腰椎BMD有相关性,但与其他全身BMD无相关性;全身BMD各指数彼此都有相关性;PMI与下颌骨相对BMD及MRI均有相关性,下颌骨BMD与MRI无相关性.结论 更年期妇女颌骨BMD与其全身BMD具有相关性,其中PMI与全身BMD的相关性最高,可以作为敏感指标初步筛查更年期妇女骨质疏松的情况.     

Relationship between mandibular cortical bone height and bone mineral density of lumbar spine

The aim of this study was to evaluate the association between lumbar spine bone mineral density and mandible cortical bone height at the mental foramen and at the angle of the jaw. PATIENTS AND METHODS: A total of 130 women living in Lithuania, were examined. None of the participants were known to have endocrine, metabolic or skeletal disorders. Bone mineral density (BMD) was measured in the spine lumbar area L2-L4. The mandibles were examined on panoramic x-ray images. On each radiograph cortical thickness of mandible was measured at the mental foramen and at the angle of the jaw. The results demonstrated a tendency of high probability of osteoporosis in cases were radiomorphometric parameters are low. There was a significant difference between bone mineral density of lumbar spine and cortical bone height of mandible below the foramen mentale and at the angle of the jaw (p<0.01).     

甲亢兔牙槽骨与全身骨密度变化的相关性研究

目的: 比较甲亢兔牙槽骨骨密度和全身骨密度的改变。方法: 将24只新西兰大白兔分成两组,每组12只(实验组,对照组),每组雌雄各半。实验组每日用左旋甲状腺素50 μg/kg·d^-1,生理盐水稀释,腹腔注射,对照组每日注射等量生理盐水。8周后进行FT3、FT4、ALP、Ca、P、Mg检测;用双能X线骨密度扫描仪对腰椎、下颌骨及双侧股骨远心端进行骨密度(BMD)检测。结果: 在给药8周后,实验组FT3、FT4、ALP、Ca、P、Mg、BMD数值与对照组比较,具有统计学意义。实验组兔牙槽骨骨密度低于对照组,腰椎,股骨骨密度低于对照组。结论: 甲亢兔牙槽骨骨密度变化与全身骨密度变化一致,呈骨质疏松状态,低于正常组。     

糖尿病大鼠牙槽骨骨密度与全身骨密度变化的相关实验研究

目的比较雌、雄性糖尿病大鼠牙槽骨骨密度的改变以及雄性糖尿病大鼠全身骨密度的改变。方法将40只Wistar大鼠分为糖尿病组（雌、雄性大鼠各15只）和对照组（雌、雄性大鼠各5只）。腹腔注射链脲佐菌素（STZ）制备糖尿病大鼠模型,检测糖尿病组和对照组大鼠血糖、血清胰岛素和骨代谢指标,检测下颌牙槽骨、股骨和腰椎的骨密度。结果对照组和糖尿病组雄性大鼠下颌牙槽骨骨密度均高于雌性大鼠（P<0.05）;糖尿病组雌、雄性大鼠下颌牙槽骨骨密度分别低于对照组雌、雄性大鼠（P<0.05）。对照组雄性大鼠的骨密度由高至低依次为股骨、下颌牙槽骨、腰椎;糖尿病组雄性大鼠的骨密度由高至低依次为下颌牙槽骨、股骨、腰椎。结论糖尿病雌、雄性大鼠下颌牙槽骨发生了糖尿病性骨质疏松,且雌性大鼠骨质疏松更严重;雄性糖尿病大鼠下颌牙槽骨、股骨和腰椎骨密度较对照组低,下颌牙槽骨骨密度变化与股骨和腰椎的变化相一致,或是糖尿病组大鼠下颌牙槽骨骨密度变化滞后于股骨和腰椎骨密度的变化。     

Role of dental panoramic radiographs in assessment of future dental conditions in patients with osteoporosis and periodontitis

Osteoporosis affects large segments of elderly populations, especially postmenopausal women. Bone mineral density (BMD) assessment of the skeleton by means of several pieces of equipment, such as dual-energy X-ray absorptiometry, have been useful in identifying individuals with low BMD or at high risk of suffering osteoporotic fracture. Recent investigators have demonstrated a significant association between BMD of the mandible and the peripheral skeleton in postmenopausal women. Some studies also have linked low BMD of the mandible and the peripheral skeleton with alveolar bone loss of the mandible and tooth loss. Dental panoramic radiology is a useful imaging modality by which the dentist can evaluate the whole dentition as well as the jawbones. Clinicians have started to focus on some mandibular panoramic indices, such as mandibular cortical index and mandibular cortical thickness, for the identification of elderly individuals who should undergo BMD assessment. In comparison with peripheral BMD measurement equipment in the medical field, the dentist will be able to identify osteoporotic elderly individuals by means of dental panoramic radiographs taken for the diagnosis of the teeth and the jawbones without additional cost. It is likely that the clinician may estimate the future risk of tooth loss in elderly individuals with periodontitis and osteoporosis by dental panoramic radiographs.     

Trabecular bone mineral density of mandible and alveolar height in postmenopausal women

Mineral density of the trabecular bone of the mandible was determined by single-energy QCT (quantitative computed tomography) for 74 totally or nearly edentulous menopausal women. These results were compared with the bone mineral densities (BMD) of their lumbar area (L2–L4) and femoral collum, measured by dual-energy x-ray transmission, Lunar DPX. The remaining height of the residual ridge at the symphysis of the mandible was measured on computed tomography (CT) lateral projection view, and an index of the residual ridge status was introduced. To determine whether general osteoporosis status affects the remaining height of the residual ridges, we compared these values with all results for bone mineral density. The BMD of the lumbar area and that of the femoral collum correlated well with each other, but the BMD of the trabecular bone of the mandible did not correlate with either of the other two BMD measurements. Measurements of residual ridge height did not correlate with any BMD values. The effect of possible bone loss earlier in life is no longer apparent in mandibular height or trabecular BMD over 20 yr after tooth extractions.     

骨质疏松症患者颌骨骨密度与全身骨密度的相关性研究

目的研究骨质疏松症患者颌骨骨密度(bone mineral density,BMD)和全身BMD的相关性。方法对40例骨质疏松症患者使用双能X线骨密度仪(DXA)测量腰椎骨和髋关节骨密度,应用计算机处理软件检测标准化数字式曲面体层片(stan-dard digital panoramic tomograph,SDPTG)下颌骨下列指标:牙槽骨BMD、下颌骨下缘皮质厚度(cortical width,CW)、曲面体层下颌指数(panoramic mandibular index,PMI)、下颌骨吸收指数(mandible resorptionindex,MRI),使用SPSS12.0进行参量间相关性分析。结果腰椎及髋关节BMD与CW有显著相关性(P<0.05);与PMI中度相关;与牙槽骨BMD及MRI没有相关性。结论下颌骨下缘皮质厚度改变与全身骨代谢间有一定的相关性。     

A comparison of bone mineral density in the spine, hip and jaws of edentulous subjects

OBJECTIVES: The aim was to investigate the relationship between bone mineral density (BMD) of the jaws (mandible and maxilla) and other skeletal sites. In addition, the influence of gender, smoking and the number of years without natural teeth were examined. MATERIALS AND METHODS: 18 edentulous patients (9 females, 9 males) with a mean age of 67.1 (sd 12.6) years had DXA scans to assess the BMD of the lumbar spine and hip, together with the ramus, body and symphysis of the mandible and the anterior of the maxilla. RESULTS: BMD values for the ramus were similar to those for the femur but significantly lower than the lumbar spine. The body and anterior mandible had higher values and the anterior maxilla lower values than both the femur and ramus. The ramus BMD showed moderately strong relationships with the standard measures of BMD in the spine and hip, but the BMD of other areas of the jaws showed no relationship with skeletal sites. The BMD for both the hip and the ramus showed an inverse relationship with increasing age. There was no statistically significant relationship between BMD of hip, spine and jaw and either years edentulous or cigarette years. (207) CONCLUSIONS: Although the ramus of the mandible may show correlation of BMD with skeletal sites, the areas of the jaws where implants may be placed do not. Therefore BMD of the skeletal sites could not be used to predict BMD of the jaws. The BMD of the jaws as measured by DXA showed no relationship with either years edentulous or cigarette smoking.     

Bone mineral content and bone metabolism in young adults with severe periodontitis

OBJECTIVES: To clarify in young adults with severe periodontitis (1) whether the bone mineral content (BMC) or density (BMD) in the mandible/other skeletal sites and the systemic bone metabolism differed from normal and (2) whether mandibular/forearm BMC did change during the 5 to 10-year follow-up. MATERIAL AND METHODS: 24 young otherwise normal patients with verified severe periodontitis were included, of which 20 attended the follow-up visit. Mandibular/forearm BMC was measured at both visits by dual-photon absorptiometry, supplemented with femoral neck/lumbar spine BMD measurements at follow-up visit by dual-energy X-ray absorptiometry. Serum alkaline phosphatase/ionized calcium, urinary excretion of pyridinoline/deoxy-pyridinoline were analysed at the follow-up visit. A conventional periodontal examination was performed at both visits. RESULTS: Mandibular BMC was significantly below normal mean BMC at both visits. The mandibular Z-scores were < or = -2.00 in 33.3% (8/24). BMC/BMD in the remaining sites and the values for bone markers did not differ from normal. Mandibular/forearm BMC was stable while a significant aggravation of alveolar bone loss occurred during the trial without change of probing depth. CONCLUSIONS: Severe periodontitis in young adults seems to be a local disorder associated with relatively low BMC in the jaws without systemic alterations of BMC/BMD and bone metabolism.