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托槽不同回收方法对摩擦力影响的实验研究

An Experimental Research on the Influnce of Different Recycling Methods of Brackets on Their Frictional Resistance

【作者】 魏玉权

【导师】 吴建勇;

【作者基本信息】 南昌大学 , 口腔正畸学, 2008, 硕士

【摘要】 目的:探讨托槽再利用不同处理方法,对托槽与弓丝间摩擦力的影响及槽沟光洁度变化。方法:本试验采用A和B两个厂家上中切牙不锈钢方丝弓托槽各90枚,随机按处理方法各分成5组,每组18枚。第一组不做任何处理作为对照组,第二组喷砂处理组(喷砂组),第三组酒精灯烧结组(灯烧组),第四组热处理并超声清洗组(热超组),第五组热处理并超声清洗再电解抛光组(热超电组)。使用0.019X 0.025英寸不锈钢方丝和0.018英寸不锈钢圆丝两种弓丝,又将每个处理方法组分成方丝组和圆丝组两个小组,每小组中随机取一枚进行扫描电镜观察托槽槽沟底光洁度。使用Instron万能材料力学实验机测量各托槽弓丝组合的静动摩擦力。结果:1、同一厂家托槽,无论在方丝组合还是圆丝组合,对照组和喷砂组的静动摩擦力都无统计学意义(P>0.05)。2、灯烧组,A托槽无论方丝组还是圆丝组,相比对照组及其它处理方法组,静动摩擦力均大,有统计学意义(P<0.05);B托槽方丝,灯烧组比对照组的静动摩擦力增大,有显著统计学意义(P<0.05);但是B托槽圆丝,灯烧组静动摩擦力相比对照组静动摩擦力无统计学意义(P>0.05)。3、热超组,A托槽静动摩擦力都明显大于对照组,具有显著的统计学差异(P<0.05);B托槽的静动摩擦力都相比其对照组,无统计学意义(P>0.05)。4、经热超电法处理,A托槽的静动摩擦力都小于其余各处理组,有显著统计学意义(P<0.05);B托槽静动摩擦力和其对照组无统计学意义(P>0.05)。5、从扫描电镜的镜下见: A托槽,对照组和喷砂组槽沟见散在的小突起,喷砂组可见散在小颗粒,灯烧组槽沟大量不规则小岛、深而大沟,热超组槽沟表面不规则深沟,热超电组槽沟表面比对照组光滑可见少量细长交错的裂痕;B托槽,对照组,热超组组均平整光滑,喷砂组散在小颗粒,但灯烧组托槽槽沟底见散在的小突起,热超电组可见大量窝沟点隙。结论:1.A托槽,经喷砂法处理后摩擦力无显著变化;经灯烧法或热超法处理后摩擦力均增大;经热超电法处理后摩擦力减小。2.B托槽,经喷砂法、热超法、热超电法任一方法处理,其摩擦力均无显著变化。3.经喷砂法、灯烧法、热超法任一方法处理,A托槽与弓丝的摩擦力大于B托槽与弓丝的摩擦力;经热超电法处理,A托槽与弓丝的摩擦力和B托槽与弓丝的摩擦力无显著差异。

【Abstract】 Objective:The purpose of this paper is to discuss the effect of different bracket recycling methods on the frictions between bracket slots and arch wires and the changes of slot glossiness.Method:This test uses 90 upper central incisor stainless steel square wire arch brackets from A and B companies. Divide them into 5 treatment groups at random with 18 brackets in each group. The first group is kept untreated as cross reference; The second group is treated by sand blasting (sand blasting group); The third group is sintered by spirit lamp (sintered group); The fourth group is treated with heat and cleaned by ultrasonic wave after the heat treatment (heat-ultrasonic group); The fifth group is treated by electrolysis polishing after heat treatment and ultrasonic wave cleaning (heat -ultrasonic-electro group). Use 0.019X0.025 in. stainless steel square wire and 0.018 in. stainless steel round wires and divide every one of the five treatment groups into 2 groups. Take one at random from each group to observe the slot glossiness. Use Instron universal dynamometer to measure the static and kinetic frictions between brackets and arch wires and observe the roughness of the slots of the brackets after different treatments with scanning electron microscope.Results:1.For brackets of the same company, no matter the square wire group or the round wire group, the static and the reference group and sand blasting group have no statistical significance (P>0.05).2.For the sintered group,“A”brackets, no matter the square wire group or round wire group, have larger static and kinetic frictions than that in reference group and other groups, and they have statistical significance(P<0.05). For square wire“B”brackets, the data of static and kinetic frictions in the sintered group, comparing with those of frictions in reference group, have statistical significance (P<0.05); But for the round wire“B”brackets in sintered group, the data of static and kinetic frictions, comparing with those of frictions in reference group, have no statistical significance(P>0.05).3. For“A”brackets, the static and kinetic frictions in heat-ultrasonic group are obviously larger than those in reference group. The data have distinct statistical significance (P<0.05). For“B”brackets, the data of the static and kinetic frictions in heat-ultrasonic group, comparing with the reference group, have no statistical significance(P>0.05).4. For“A”brackets, the static and kinetic frictions after heat, electrolysis and ultrasonic treatment are obviously smaller than those other groups. The data have distinct statistical significance (P<0.05), For“B”brackets, the data of the static and kinetic frictions and those of reference group have no statistical significance (P>0.05).5. It can be observed from scanning electron microscope: for“A”brackets, there are small protrusion in the slots of reference group and sand blasting group brackets, small granules can be seen in sand blasting group brackets; there are large amount of irregular isles and deep large gully in sintered group brackets; there are irregular deep gully on the surface of brackets in heat-ultrasonic group; the surface in heat-electro-ultrasonic group is smoother than that of reference group but slight interlaced cracks can be seen. For“B”brackets, the ones in reference and heat-ultrasonic groups are smooth and flat; There are small granules in sand blasting group brackets; there are small protrusions in the slot of sintered group brackets and large amount of slot pits can be found in heat -ultrasonic-electro group brackets.Conclusions:1. For“A”brackets, the frictions have no distinct changes after sand blasting; they increase in the sintered group and heat-ultrasonic group and decrease in heat-electro-ultrasonic group.2. For“B”brackets, the fictions have no distinct changes in any of the groups.3. The frictions between“A”brackets and arch wires are larger than those between “B”brackets and arch wires in sand blasting group, sintered group and heat-ultrasonic group. But there is no distinct difference between the two in heat -ultrasonic-electro group.

【关键词】 托槽摩擦力热处理喷砂电解抛光
【Key words】 bracketfrictionheat treatmentsand blastingelectrolysis polishing
  • 【网络出版投稿人】 南昌大学
  • 【网络出版年期】2009年 01期
  • 【分类号】R783.5
  • 【被引频次】2
  • 【下载频次】55
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