目的 研究临床上精细抛光对二氧化锆及钴铬合金修复体材料与天然牙间磨耗的影响.方法 使用表面粗糙度仪测量修复体材料抛光前后的粗糙度值(Ra).在摩擦磨损测试机上,模拟口腔内的力学和化学环境,进行天然牙与不同处理的修复体材料间的摩擦磨损实验,测量两者间摩擦系数(μ).测量实验前后各磨擦对象的自身质量损失(Δm),扫描电镜观察实验后天然牙表面.结果 各实验组中表面Ra,不烧结饰瓷抛光组(0.933±0.186)μm小于不抛光组(2.350±0.327)μm(P=0.000);烧结饰瓷组抛光组(2.300±0.189)μm小于不抛光组(4.200±0.871)μm(P=0.000);钴铬合金抛光组(0.250±0.083)μm小于不抛光组(1.200±0.894)μm(P=0.000),有统计学意义.对磨天然牙自身质量损失量(Δm),不烧结饰瓷抛光组(6.067±0.921)mg小于不抛光组(16.690±2.113)mg(P=0.001);烧结饰瓷抛光组(5.893±0.838)mg小于不抛光组(14.016±0.063)mg(P=0.000);钴铬合金抛光组(4.573±1.954)mg小于不抛光组(11.433±1.087)mg(P=0.008)有统计学意义.各组修复材料自身质量损失量(Δm)不烧结饰瓷抛光组(0.300±0.010)mg小于不抛光组(0.800±0.010)mg(P=0.001);烧结饰瓷抛光组(0.456±0.055)mg小于不抛光组(0.650±0.086)mg(P=0.031);钴铬合金抛光组(10.236±0.357)mg小于不抛光组(14.300±0.526)mg(P=0.000)有统计学意义.抛光组的摩擦系数:不烧结饰瓷氧化锆0.068,烧结饰瓷热氧化锆0.095,钴铬合金0.063明显小于不抛光组不烧结饰瓷二氧化锆0.096,烧结饰瓷二氧化锆0.119,钴铬合金0.103,差异有统计学意义.结论 修复体表面精细抛光,可以有效降低其表面粗糙度,减小其与牙釉质间的摩擦系数,避免天然牙的过度磨耗.%Objective To investigate the effect of fine polishing on the abrasion between natural tooth and zirconia,or cobalt-chromi-um alloy.Methods The surface roughness value was measured to analyze surface roughness of zirconia,glazed-zirconia and cobalt-chromium alloy before and after fine polishing.The friction coefficient between restoration materials and natural enamel was measured,friction and wear experiment was carried out between natural tooth and three kinds of materials under presupposed condition,which simulated oral chemistry environment by artificial saliva and mechanical property by wear and abrasion test machine.Every sample was weighed pretest-posttest to calculate volume loss.Scanning electron microscopy was used to analyze surface characteristic of post-experi-ment natural tooth.Results The roughness value of polished zirconia group(0.933±0.186)μm was significantly smaller than ziconia group(2.350±0.327)μm without polishing(P=0.000).Polished glazed-zirconia group(2.300±0.189)μm and glazed-zirconia group (4.200±0.871)μm,polished cobalt-chromium ally group(0.250±0.083)μm and cobalt-chromium ally group(1.200±0.894)μm had the same result(P=0.000).The volume loss of natural tooth for polished zirconia group(6.067±0.921)mg was significantly smaller than zirconia group(16.690±2.113)mg without polishing(P=0.001).Polished glazed-zirconia group(5.893±0.838)mg and glazed-zirconia group(14.016±0.063)mg(P=0.000),polished cobalt-chromium ally group(4.573±1.954)mg and cobalt-chromium group(11.433±1.087)mg(P=0.008)had the same result.The volume loss of restoration for polished zirconia group(0.300±0.010)mg was significantly smaller than zirconia group(0.800 ± 0.010)mg without polishing(P=0.001).Polished glazed-zirconia group(0.456 ± 0.055)mg and glazed-zirconia group(0.650±0.086)mg(P=0.031),polished cobalt-chromium ally group(10.236±0.357)mg and cobalt-chromium group(14.300±0.526)mg(P=0.000)had the same result.The friction coefficient between polished zirconia and natural tooth(0.068) was significantly smaller than that between zirconia and natural tooth(0.096)(P=0.001).Glazed-zirconia and cobalt-chromium ally had the same result(P=0.001).Conclusions Fine polishing significantly reduces the roughness of restoration surface and the friction coefficient between restoration and natural tooth,so it can avoid severe tooth wear.
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