BackgroundRecent studies suggest a role for microscopic crystalline particles of residual dental calculus in the pathogenesis of periodontitis. The purpose of this ex vivo study was to compare the effectiveness of scaling and root planing (SRP) alone versus SRP combined with 24% ethylenediamine‐tetra acetic acid (EDTA) gel in removing calculus from extracted teeth and to determine the optimal length of time for application of the EDTA.MethodsSpecimens consisted of 32 extracted teeth with heavy root calculus. A 4‐mm diameter site was prepared on the root surface of each tooth which then underwent SRP. EDTA was applied to four timed groups: 30 s; 60 s; 120 s; and 180 s. Photomicrographs were taken at 40× magnification using white light (WL) and laser fluorescence (LF). Photomicrographs were analyzed using ImageJ. Specimens were also evaluated with scanning electron microscopy (SEM).ResultsThe mean area of residual calculus after SRP was 45%–53% (45.6% ± 19.6% WL, 53.8% ± 19.7% LF). Burnishing with EDTA for one minute following SRP reduced calculus to only 14%–18% (13.9% ± 12.5% LF, 18.2% ± 11.1% WL). Use of EDTA for greater than 1 min showed no further calculus removal. SEM revealed the surface of remaining calculus was altered by burnishing with EDTA.ConclusionSRP alone or SRP + 24% EDTA gel failed to remove all calculus. SRP alone removed >60% of calculus from root surfaces. Adjunctive use of 24% EDTA gel burnished on the root surface removed most of the calculus residual after SRP. Calculus remaining after EDTA burnishing exhibited a significantly altered morphologic appearance.

中文翻译：

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激光和扫描电子显微镜评估结石残留微岛


背景最近的研究表明残留牙结石的微观结晶颗粒在牙周炎的发病机制中发挥着作用。这项离体研究的目的是比较单独洁治和根面平整 (SRP) 与 SRP 联合 24% 乙二胺四乙酸 (EDTA) 凝胶去除拔牙牙石的效果，并确定最佳时间长度方法标本由 32 颗拔除的牙齿组成，牙根结石较多。在每颗牙齿的根部表面制备一个直径为 4 毫米的部位，然后进行 SRP。 EDTA应用于四个计时组：30秒； 60 秒； 120 秒；和 180 秒。使用白光 (WL) 和激光荧光 (LF) 在 40 倍放大倍数下拍摄显微照片。使用 ImageJ 分析显微照片。还用扫描电子显微镜 (SEM) 对标本进行了评估。结果 SRP 后残留牙石的平均面积为 45%–53%（45.6% ± 19.6% WL，53.8% ± 19.7% LF）。 SRP 后用 EDTA 抛光一分钟，牙结石仅减少 14%–18%（13.9% ± 12.5% LF，18.2% ± 11.1% WL）。使用 EDTA 超过 1 分钟未显示出进一步的牙石去除。 SEM显示残留牙石的表面因EDTA抛光而发生改变。结论单独SRP或SRP+24%EDTA凝胶未能去除所有牙石。仅 SRP 可去除根面 60% 以上的牙石。辅助使用 24% EDTA 凝胶对牙根表面进行抛光，去除了 SRP 后残留的大部分牙石。 EDTA 抛光后残留的牙石表现出显着改变的形态外观。