Quantitative Study in Absorption of Mandible Caused by Aging and Disease.

衰老和疾病引起的下颌骨吸收的定量研究。

• 批准号: 07457466
• 负责人: NAGAO Masanori
• 金额: $ 0.51万
• 依托单位: Tokyo Medical and Dental University, Grant-in-Aid for Scientific Reserch (B) (2)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07457466/
• 关键词: bone mineral content; quantitative image; measurement system; 骨塩量定量; 顎骨吸収; X線

Absorption of mandible is caused by both local and general disease as well as aging and prosthetic factors, that is local stimuli on teeth, mandibular bone and residual ridge caused by dental prostheses. It is useful information for prosthetic treatment, design and prognosis of prosthetics.To understand absorption of mandible, we need to know relations among absorption of mandible, local stimuli which denture makes and bone disease like osteoporosis which aged people is susceptible to. It is also be necessary to seek possibility of screening people suffering from osteoporosis.There are many studies in absorption of madible with biochemistry, histology and radiology. Recently changes of trabecular bone mineral density have become a center of attraction. However, there is no quantitative study in absorption of madible. Some measurement system requires particular facilities, and there is no simple method which can make high-accuracy measurements of bone mineral content.Thus, we developed a measurement sytem which is based on computed radiography system, coming into wide use. This system includes a Sn, Cds filtration which produces very rittle effect of tube potential change and unevenness of photo density and an air gap of 10 cm which reduce effect of scattered fraction for contrast improvement. Accordingly a measurement error was less than 10mg/cm^2 in range from 0 to 800mg/cm^2, and it was found that this system is useful for detecting changes of trabecular bone mineral density. Using filter which has lower Kedge potential than Cd or Sn may allow us to expand the range of measurement.

下颌骨的吸收既有局部和全身疾病，也有衰老和修复因素，即局部刺激牙齿、下颌骨和修复后残留的牙槽骨。为了了解下颌骨吸收与义齿所产生的局部刺激、老年人易患骨质疏松等骨病之间的关系，需要了解下颌骨吸收与义齿局部刺激的关系。也有必要寻求对骨质疏松患者进行筛查的可能性。从生化、组织学和放射学的角度对可食性物质的吸收进行了大量的研究。近年来，骨小梁骨密度的变化成为人们关注的焦点。然而，目前还没有关于可食用药物吸收的定量研究。一些测量系统需要特殊的设备，没有简单的方法可以对骨矿含量进行高精度的测量，因此，我们开发了一种基于计算机X射线成像系统的测量系统，得到了广泛的应用。该系统包括一个锡、硫化镉滤光器和一个10厘米的气隙，该滤光器可以产生非常精确的管子电位变化和光密度不均匀的影响，从而减少散射分数的影响，从而提高对比度。在0~800 mg/cm~2范围内，测量误差小于10 mg/cm~2，可用于骨小梁密度变化的检测。使用比Cd或Sn更低Kedge电势的滤光片，可以扩大测量范围。