Coelho Marcelo Santos, Card Steven J, Tawil Peter Z
Department of Endodontics, Universidade Paulista School of Dentistry, Sorocaba, SP, Brazil.
Department of Endodontics, University of North Carolina School of Dentistry, Chapel Hill, NC, USA.
Restor Dent Endod. 2017 Aug;42(3):232-239. doi: 10.5395/rde.2017.42.3.232. Epub 2017 Jul 24.
The evaluation of iatrogenic dentinal defects in extracted teeth may be influenced by extraction forces and prolonged dry times. The purpose of this study was to compare the presence of dentinal defects in freshly extracted, periodontally compromised teeth with those in a group of teeth with uncontrolled extraction forces and storage time.
The experimental group consisted of eighteen roots obtained from teeth extracted due to periodontal reasons with class II or III mobility. They were kept in saline and sectioned within 1 hour following extraction. The control group consisted of matched root types obtained from an anonymous tooth collection, consistent with previous dentinal defect studies. The slices were obtained at 3, 6, and 9 mm from the apex. The imaging process exposed all specimens to no more than 60 seconds of dry time. The × 12.8 magnification was used for the 9 mm slices and × 19.2 magnification for the 3 mm and 6 mm slices under light-emitting diode (LED) transillumination. The root canal spaces and periodontal tissues were masked to minimize extraneous factors that might influence the evaluators. Chi-square test was used for statistical analysis.
Dentinal defects were detected in 17% of the experimental group teeth, compared to 61% of control teeth ( = 0.015).
LED transillumination assessment of freshly extracted roots with class II or III mobility showed smaller number of dentinal defects than roots with uncontrolled storage time and extraction forces. The use of freshly extracted roots with mobility should be considered for future dental defect assessment studies.
拔牙过程中的外力及过长的干燥时间可能会影响对拔除牙齿医源性牙本质缺损的评估。本研究的目的是比较新鲜拔除的、存在牙周问题的牙齿与一组拔牙外力及保存时间不受控制的牙齿中牙本质缺损的情况。
实验组由18颗因牙周原因拔除的、具有Ⅱ度或Ⅲ度松动的牙根组成。将它们保存在盐水中，并在拔牙后1小时内进行切片。对照组由从匿名牙齿收集库中获取的匹配牙根类型组成，与先前的牙本质缺损研究一致。切片取自根尖3、6和9毫米处。成像过程中所有标本的干燥时间不超过60秒。在发光二极管（LED）透照下，9毫米切片使用×12.8倍放大倍数，3毫米和6毫米切片使用×19.2倍放大倍数。根管空间和牙周组织进行了遮盖，以尽量减少可能影响评估者的外部因素。采用卡方检验进行统计分析。
实验组牙齿中检测到牙本质缺损的比例为17%，而对照组牙齿为61%（P = 0.015）。
对具有Ⅱ度或Ⅲ度松动的新鲜拔除牙根进行LED透照评估时，发现牙本质缺损的数量少于拔牙外力及保存时间不受控制的牙根。未来的牙齿缺损评估研究应考虑使用具有松动度的新鲜拔除牙根。
