Determination of the Root Canal Length of Teeth of Bantu Patients Attending the Teaching Hospital of Kinshasa University

Background: There is paucity of literature on the determination of the root canal length of Bantu subjects in dental professional practicing in Africa and Democratic Republic of Congo in particular. Aims: The aim of the present study was to determine the root canal length of teeth of Bantu patients extracts attending the Teaching Hospital of Kinshasa University. Methods and Material: Prospective cross-sectional study was carried out in the service of Conservative Dentistry. The patients suffering with pulpitis of permanent teeth which were selected for root canal treatment during the period of January 2014 to December 2016 were included. All patients whose main root canals were inaccessible, teeth carrying prosthesis, teeth with large coronal decay, teeth having periapical periodontitis, supernumerary teeth, wisdom and primary teeth were excluded. Results: The upper canines presented some significant longer canals compared to the lower canine (23.4 ± 2.3 mm and 21.6 ± 1.8 mm). Palatal canals of the first and second molar were respectively longer as compared to the superior teeth canals (21.5 ± 1 mm, 21.3 ± 2 mm). The distal canals of the first and second molar were the longest in the mandibular arch respectively measuring 20.7 ± 2.0 mm and 21.5 ± 1.7 mm. Conclusion: Data obtained from Bantu patients show slightly shorter roots compared to some European populations, but longer than some Asian populations.

Tooth anatomy risk factors influencing root canal working length accessibility

The aim of this study was to analyze the specific influence of root canal anatomy on the accessibility of working length during root canal therapy. Four hundred seventy-six root canal therapy cases （amounting to a total of 1 005 root canals） were examined. The anatomy risk factors assessed in each case included： tooth type （tooth location）, root canal curvature, and root canal calcification, as well as endodontic retreatment. The investigation examined the correlation between each of these anatomic factors and the working length, with statistical analysis consisting of Chi-square tests and multiple logistic regression analysis. In an independent factor analysis, tooth type （tooth iocation）, root canal curvature, canal calcification, and endodontic retreatment were determined to be the primary risk factors. In a multiple-factor regression model, root curvature and canal calcification were found to most significantly influence root canal working length accessibility （P〈0.05）. Root canal anatomy increases the difficulty of root canal preparation. Appropriate consideration of tooth anatomy will assist in accurate determination of preparation difficulty before instrumentation. This study alerts clinical therapists to anatomical factors influencing the working length accessibility, and allows for a direct estimate of success rate given in situ measurements of tooth factors during the root canal treatment procedure.

An in vitro study on the efficacy of removing calcium hydroxide from curved root canal systems in root canal therapy

To compare the efficacy of various irrigants(citric acid, ethylenediaminetetraacetic acid(EDTA) and Na OCl) and techniques in removing Ca(OH)2in two types of curved root canal systems, simulated root canals with specific curvatures were used to investigate the effects of different irrigants and instruments on Ca(OH)2removal. The optimal methods were verified on extracted human teeth. Simulated root canals were assigned to one of two groups based on the irrigation solution: 10% citric acid or2.5% Na OCl. Each group was divided into four subgroups according to the technique used to remove Ca(OH)2. The percentage of Ca(OH)2removal in different sections of root canals was calculated. On the basis of the results obtained for the simulated canals, 10% citric acid and 17% EDTA were applied to remove Ca(OH)2from the extracted human teeth with curved root canal systems. The teeth were scanned by micro computed tomography to calculate the percentage of Ca(OH)2removal in the canals.In simulated root canals, we found that 10% citric acid removed more Ca(OH)2than 2.5% NaOCl in the 0–1 mm group from the apex level(Po0.05). Ultrasonic and Endo Activator activation significantly removed more Ca(OH)2than a size 30 K file in the apical third(Po0.05). However, there were no significant differences in any sections of the canals for 10% citric acid or 17%EDTA in removing Ca(OH)2in extracted human teeth. We concluded that it was effective to remove residual Ca(OH)2using the decalcifying solution with Endo Activator or Passive Ultrasonic Irrigation in a curved root canal system. A protocol for Ca(OH)2removal was provided based on the conclusions of this study and the methods recommended in previous studies.

Efficacy of Solution Form of Ethylenediaminetetraacetic Acid on Removing Smear Layer of Root Canal at Different Exposure Time In Vitro

Summary： This study was aimed to evaluate the effectiveness of solution form of 17% ethylenediaminetetraacetic acid （EDTA） on removing smear layer of root canals at different exposure time periods and to provide scientific basis for EDTA as a choice of root canal irrigation in clinical practice. Twenty-five single-rooted teeth were randomly divided into 5 groups： control group （group A） was given 2.5% NaOC1, and 4 experimental groups were given 2.5% NaOC1 and 17% EDTA, including groups B, C, D and E with exposure time of 1, 3, 5 and 7 min, respectively. After preparation of the root canals, the teeth were split along their longitudinal axis, and the root sections were examined under scanning elec- tron microscope for evaluation of smear layer removal and erosion on the surface of the root canal walls. The specimens in group B showed presence of smear layer on the walls of the root canal with no statistical difference from that in group A （P〉0.05）. In groups C and D, partial removal of smear layer was obtained, and there was no significant difference between the two groups （P〉0.05）, but there was significant difference in removal of smear layer between group C and group B （P〈0.05）. Root canal walls in group E specimens showed almost complete removal of smear layer, and the removal of smear layer was significantly different from that in group D （P〈0.01）. There was no significant change in the structure of the surface of root canal for each sample. It was concluded that combined irrigation with 17% EDTA and 2.5% NaOC1 could remove the smear layer with no significant alteration in dentinal structure when the chelating agent was applied for 7 min. At 3 and 5 min of application, partial removal of smear layer was observed and at 1 min negligible removal of smear layer was achieved.

Calcium Hydroxide Removal in Curved Root Canals with Apical Transportation In Vitro

Calcium hydroxide（CH） is applied to improve disinfection of root canals in most root canal retreatment. This study aimed to analyze the CH removal efficacy using 7 different root preparing files（K file, pre-curved K file, EndoActivator, Ultrasonic file, pre-curved ultrasonic file, F file and needle irrigation alone） with apical transportation. Standardized models of curved canal with such apical transportation or not were set up before applying CH to root canal for 7 days. Seven techniques described above were used for its removal. Then the roots were disassembled and digital photos were taken. The ratio of residual CH in the overall canal surface was calculated using the image analyzer image pro plus 6.0. The data were analyzed using one-way ANOVA with post hoc Tukey test. Results revealed that CH was effectively removed（P〈0.05） by using all 6 mechanical methods except irrigation alone. In curved root canals with apical transportation, EndoActivator, pre-curved ultrasonic file and F file were found to be more effective in removing CH than the other four file（P〈0.001）, while there was no significant difference among EndoActivator, pre-curved ultrasonic file and F file groups（P〉0.05）. The percentage of residual CH in the canal with apical transportation was higher than that in the canal without apical transportation（P〈0.05）. In conclusion, CH can be hardly removed completely. Canal with apical transportation will result in insufficient CH removal. EndoActivator, pre-curved ultrasonic file and F file are more effective in the curved root canal with apical transportation.

体内不同冲洗液对ROOT ZX电测仪准确性的影响

目的:体内评价不同冲洗液对Root ZX根尖电测仪测量结果的影响。方法:150颗需根管治疗的单根管牙随机分为5组,开髓,冠向敞开后同时去除根管内牙髓后分别以3%H2O2、17%EDTA、0.5%NaOCl、生理盐水冲洗根管3次,最后一次保留冲洗液,进行根管测量。空白组为0.5%次氯酸钠和生理盐水交替冲洗后的干燥根管。各组测量3次的平均值与X片确定的根管长度值以单因素方差分析(ANOVA)分析各组间差异。结果:各组根管长度测量值与实际根管长度无显著性差异,单因素方差分析显示各组间测量值无显著性差异。结论:ROOT ZX根尖定位仪能准确测量根管长度,且不受根管内冲洗液的影响。

Root ZX根管测量仪与三联法对根管充填质量的比较研究

目的比较研究Root ZX根管长度测量仪与三联法对根管充填质量的影响。方法随机选择需行根管治疗术的单根管恒前牙、双尖牙320颗,分为两组,在根管预备前分别应用Root ZX根管测量仪与三联法测量根管长度,以此长度进行预备和充填,然后摄牙片,比较其准确率。结果两种方法充填根管X线片结果差异明显,电测组适充率为91.41%,三联法组适充率为68.71%。电测组明显优于三联法组(P<0.05)。结论Root ZX测量仪是一种安全可靠、准确率高的根管长度测量仪。

ROOT ZX根尖定位仪测量老年人后牙牙齿操作长度的应用

目的 :探讨ROOTZX根尖定位仪测量老年人后牙牙齿操作长度的准确性和实用性。方法 :选择 12 9例拟行根管治疗的 6 0岁以上老年患者 ,共计 137个后牙 ,330个根管。将患者随机分成两组 ,实验组采用ROOTZX根尖定位仪测量牙齿操作长度 ,对照组采用感觉法估计牙齿操作长度 ,进行常规根管预备、根管充填后摄X线牙片了解其准确性。结果 :实验组充填成功率明显高于对照组 (P <0 .0 1)。结论 :ROOTZX根尖定位仪测量老年人后牙牙齿操作长度的准确性较高。

Root-ZX根管长度测定仪临床应用体会

目的:探讨Root-ZX根管长度测量仪测量根管长度的准确性。方法:将131例(242个)需进行治疗的根管随机分为实验组和对照组,实验组43例(83个根管)采用Root-ZX根管长度测定仪测定根管工作长度;对照组88例(159个根管)采用X线片+诊断丝方法测量根管工作长度。两组均采用冠向下技术进行根管预备,插30#牙胶尖拍片评价2种方法测量根管工作长度的准确性并进行比较。结果:实验组83个根管中68个根管测量准确,15个不准确;对照组159个根管中94个测量准确,65个不准确。两组差异有统计学意义(χ2=12.819,P<0.01)。结论:Root-ZX根管长度测定仪测定根管工作长度比X线片+诊断丝测量方法更加准确。

ROOT ZX根尖定位仪测量老年人后牙工作长度准确性研究

目的:研究ROOT ZX根尖定位仪在确定老年人后牙工作长度方面的准确性。方法:随机选择86例拟进行根管治疗的老年人后牙,共计148颗后牙,实验组68颗,共183个根管,采用ROOT ZX根尖定位仪确定工作长度;对照组80颗,共209个根管为X线片组作为标准组;所有根管预备后插诊断丝摄X线片,比较实验组和标准组测定工作长度的准确性。结果:实验组中183个根管中符合工作长度标准的有173个,准确率为94.53%;对照组209个根管中符合工作长度标准的有198个,准确率为95.21%。经统计学分析,两组比较无统计学意义。结论:ROOT ZX根尖定位仪在确定老年人后牙工作长度方面与X线法可取得同样的效果,并能简化操作、避免X线的损害。

Root ZX根管长度测量仪的临床应用评价

目的评价Root ZX根管长度测量仪测量根管长度的准确性,分析出现偏差的可能因素。方法临床554个根管随机分为二组,分别用Root ZX和插针定位X线测量根管长度,根充后拍X线片检查充填效果,根据牙片上根管充填物和根尖平面关系定出三个等级。结果Root ZX组和X线组在根充超充方面比较有显著的统计学差异,P≤0．01;而在根充适充及欠充方面,二者比较无统计学差异。提示应用Root ZX根管长度测量仪所得到的工作长度比X线法准确。结论Root ZX根管长度测量仪可作为根管长度测量的一种方法。

根管锉尖直径对Root ZX测量仪准确性影响的研究

目的：研究根管预备时根管锉尖直径对Root ZX根管长度测量仪精确度的影响。方法：40颗正畸减数离体下颌前磨牙，15#不锈钢根管锉测量预备前根管的真实长度。K锉分别根管预备至主锉为40#（常规预备）和60#（过度预备），离体牙植入20g／L的琼脂生理盐水凝胶中，15—40#和15～60#K锉分别再次测量预备后根管的工作长度。所有测量值进行方差分析。结果：根管锉尖直径和根管扩大程度对测量仪的准确性有显著性影响（P〈0．05），最大测量值差别为0．22mm。结论：根管预备完成后，使用锉尖直径较小的根管锉会使电测根管工作长度变小，根管预备完成后或根充前应选用与根管直径匹配的根管锉再次确认根管工作长度。

ROOT ZX根管长度测量仪临床应用评价

目的评价森田ROOT ZX根管长度测量仪临床应用价值。方法用根管长度测量仪对108例根管进行根管测量,以此长度进行根管预备后,按测量长度插入牙胶尖摄X线牙片,计算出实际根管长度,求得测量准确率。结果ROOT ZX测量准确率为92.6%。结论ROOT ZX根管长度测量仪应用安全可靠、准确率高。

Root ZX根尖定位仪的临床应用评价

目的评价Root ZX根尖定位仪与X线法测定根管工作长度结果的符合性,从而探讨Root ZX根尖定位仪测定根管工作长度的准确性。方法选择临床上共98颗患牙共196个根管为研究对象,Root ZX根尖定位仪测定牙根管工作长度,充分预备后X线片法测牙根管工作长度,两者进行比较并进行统计学分析。结果 Root ZX根尖定位仪测量根管工作长度与X线片法测定的一致率为89.8%,单根和多根牙的结果无显著性差异。结论 Root ZX根尖定位仪测量根管工作长度准确率较高,可作为根管工作长度的常规测量,必要时用X线法校正能进一步提高根管治疗质量。

不同根管环境对Root ZX和ProPex准确性的影响研究

目的评价不同根管环境时,Root ZX和ProPex2种根管长度测量仪的测量准确性。方法选取新鲜拔除的30颗下颌单根管前磨牙,测量根管实际长度(L)后,在4种测量环境(3%H2O2溶液、0.9%NaCl溶液、2.5%NaClO溶液、根管干燥状态)下,用根管长度测量仪Root ZX和ProPex测量根管长度,得到工作长度L(R使用Root ZX测量值)和L(P使用ProPex测量值),再将上述样本沿牙根纵轴方向,用金刚砂车针磨出剖面,测量根尖剖面最狭窄点至解剖根尖孔的距离(D),计算L与D的差值得到根管实际工作长度。结果使用不同冲洗液(3%H2O2溶液、0.9%NaCl溶液、2.5%NaClO溶液)冲洗根管及根管干燥状态时,Root ZX和ProPex测定的工作长度与根管实际工作长度的差异无统计学意义(P>0.05);相同根管环境时,Root ZX和ProPex测量偏差有统计学意义(P<0.05),但在±0.5mm范围内,Root ZX和ProPex的测量准确率的差异无统计学意义(P>0.05)。结论Root ZX和ProPex测量准确性不受根管环境影响,与根管干燥和湿润无关,且两者的测量准确性无明显差异。

Root ZX在老年人后牙不同根管条件下的临床应用

目的:评价Root ZX在老年人牙髓病、根管再治疗中的应用,探讨其适用范围及操作注意事项。方法:随机选取58颗老年人后牙共148个根管作为研究对象,分为2组:A组,活髓牙;B组,根管再治疗牙。均用ProTaper进行根管预备,Root ZX测量预备前后根管工作长度,根管充填术后摄X线片评价准确性,随访2年。结果:A组,有74.7%根管在预备后工作长度超过预备前。B组,预备前后无明显差别。二组X线检查示,恰填率差异有显著性(P<0.01)。2年后治疗有效率89.2%,组间差异无显著性。结论:用Root ZX测量老年人的后牙根管长度,符合解剖生理情况,可以提高测量的准确性,提高治疗成功率。

Root ZX根管长度测量仪的应用研究进展

根管治疗术是治疗牙髓病、根尖周病首选的方法,而根管工作长度的准确测定是完善根管治疗的关键,采用Root ZX测量根管工作长度是目前临床上使用较多的一种准确测量的方法。本文对影响Root ZX测量的因素及其临床应用进行了阐述,说明Root ZX能准确测定根管工作长度,从而提高了根管治疗的效果,具有广泛的临床应用前景。

Root ZX根管测量仪与X线片测量根管长度的比较研究

目的比较Root ZX型根管长度测量仪与X线片定位法对根管长度测量的准确性。方法选取门诊需根管治疗的病例107颗患牙,根管总数213个,采用G钻预备根管口,Root ZX根管长度测量仪初测根管长度后,插K锉以标准投照技术拍摄X线片,测量诊断丝距根尖的距离用以评价Root ZX测量的准确性。结果 Root ZX根管长度测量仪与X线片测量根管长度无显著差异(P>0.05),误差在±0.5mm内的根管数有207个,准确率达97.18%。结论 Root ZX根管长度测量仪可用于临床,是一种准确性较高,重复性较好,能减少X线损害的根管治疗定位仪器。

根尖闭锁状态下Root ZX测量准确性的体外研究

目的研究根尖闭锁对根管长度电测仪Root ZX测量准确性的影响。方法选取25颗单根管离体牙,在根尖闭锁和通畅两种状态下,当K锉深入根管相同长度(锉尖距根尖约1 mm)时,Root ZX刻度表显示K锉锉尖距根尖有不同的长度。对两种状态下测得的不同长度进行比较。结果根尖闭锁和通畅两种状态下Root ZX刻度表显示的K锉锉尖距根尖的长度比较,差异有统计学意义(t=25.41,P<0.05)。结论根尖闭锁是影响根管长度电测仪Root ZX测量准确性的重要因素。

Root ZX根管长度电测仪临床准确性评价

目的探讨Root ZX电侧仪测量牙齿根管工作长度的临床准确性。方法应用Root ZX对102例113颗牙齿的208个根管进行工作长度测量及预备后插入主尖拍摄X-线片,核实并评价RootZX的准确性。结果Root ZX的准确率与牙位、年龄和牙髓状态无关,在活髓牙和死髓牙的准确率分别为93.18%、90%,二者的准确率差异无统计学意义(P<0.05);但与死髓牙相比,活髓牙根管工作长度测量值与实际值之差的平均值(即WL测-WL实的平均值)偏小。结论Root ZX根管长度电测仪临床准确率较高,可减少X-线摄入量,满足临床应用要求。