Effect of diabetes mellitus on total amount of bone resorption in the tissues under denture base bearing masticatory pressure

糖尿病对义齿支撑组织骨动力学的影响尚未得到足够的研究。本研究采用骨组织形态学法研究糖尿病对义齿基托承受咀嚼压力组织骨吸收的影响。以Wistar菌株链球菌佐菌素诱导的糖尿病雄性大鼠250只（n=50X5组）为研究对象。义齿基托应用于22周龄的硬腭磨牙区。在加载组中，义齿基托分别对上颚施加1.0、10.0和20.0 kPa的咀嚼压力。覆盖组义齿基托与上颚接触，无机械压力。不佩戴义齿组不进行有意治疗。每隔3或4天清洗上颚和活动义齿基托。每组5只大鼠在义齿植入后每隔1周切除腭组织块。标本用Villanueva骨染色剂染色，包埋在甲基丙烯酸甲酯中，正面磨至50μm厚度。利用二维图形分析系统计算侵蚀面和破骨细胞面。骨吸收量按(A)-(B)计算；(A)覆盖组在义齿植入前12周形成的骨组织，(B)各骨吸收组在各实验时段骨吸收结束后的剩余骨组织。10.0 kPa组和20.0 kPa组分别观察到义齿植入后6周骨吸收情况。10.0 kPa组骨吸收总量为189±38μm， 20.0 kPa组为266±27μm。与正常大鼠在相同条件下的结果比较，表明糖尿病使骨吸收周期延长，骨吸收总量增加。

The effect of diabetes mellitus on-bone dynamics in denture supporting tissue has not been investigated enough. The purpose of this study was to investigate the effect of diabetes mellitus on bone resorption in the tissues under denture base bearing masticatory pressure by using bone histomorphometry.Two-hundred and fifty streptozotocin-induced diabetic male rats (n=50X5 groups) of Wistar strain were used in this study. Denture base was applied to the molar region of the hard palate at 22 weeks of age. In loaded groups, the denture base were designed to load a masticatory pressure of 1.0, 10.0 or 20.0 kPa to the palate, respectively. In covering group, the denture base was designed to contact with the palate without any mechanical pressure. The non-denture-wearing group received no intentional treatment. The cleansing of the palate and removable denture base was carried out at 3 or 4 day intervals. Palatal tissue block was excised from 5 rats of each experimental group after the denture insertion at one week interval. The specimens were stained with Villanueva bone stain, embedded in methyl-methacrylate, and ground frontally to 50μm thickness. Eroded surface and osteoclast surface were calculated by using two-dimensional graphic analyzing system. Amount of bone resorption was calculated as (A)-(B) ; (A) Formed bone tissue during 12 weeks prior to the denture insertion in covering group, (B) Remained bone tissue after the end of bone resorption in each bone resorbed group at each experimental period.Bone resorption was observed in 10.0 and 20.0 kPa groups until 6 weeks after the denture insertion, respectively. Total amount of bone resorption was 189±38μm in 10.0 kPa group and 266±27μm in 20.0 kPa group. Comparing these results with results in normal rats in same condition as this study, it is showed that diabetes mellitus prolongs the period of bone resorption and increases total amount of bone resorption.