Raypex 5根尖定位仪测定牙根管长度的准确率及影响因素分析

目的 观察Raypex 5根尖定位仪测定牙根管长度的准确率,探讨影响准确率的因素.方法 选择210例牙髓病及根尖周病患者,其中225颗患牙含416个根管,先用手感法测量长度,再用根尖定位仪测定长度,充填主牙胶尖后在数字化X线成像系统上拍片确定牙齿工作长度,两者对比并进行统计学处理.结果 Raypex 5根尖定位仪测定牙根管长度准确率为93.99％,手感法准确率为74.76％.两者差异具有统计学意义（P＜0.05）;根尖定位仪测量单根管至四根管的准确率明显高于手感法,两者间的差异也具有统计学意义（P＜0.05）.结论 Raypex 5根尖定位仪测定牙根管长度操作简便,较少的X线辐射,准确率较高.     

Raypex 5根尖定位仪临床应用的准确性观察分析

目的：观察Raypex 5在临床应用中测量根管工作长度的准确性及影响因素。方法：共收集342例患者的903个根管,随机分为实验组和对照组。实验组458个根管采用Raypex 5测量根管工作长度。对照组445个根管,按手感法测量根管工作长度,拍摄X线片,分析比较,研究其准确性及影响因素。结果：在X线片上恰填范围内,实验组准确率达94.32%,对照组75.06%。电测法与手感法的准确率比较有显著性差异（P〈0.01）。牙髓活力,根尖骨质破坏状况,龋洞类型,牙位,牙齿形态,根管数目对Raypex 5测量根管工作长度的准确性无明显影响。结论：根尖定位仪Raypex 5能较为准确地测量根管工作长度,准确率比手感法高,值得临床推广使用。     

根尖定位仪测量根尖破坏牙根管长度的准确性研究

目的 比较Root ZX,Propex,Justy Ⅱ和 Raypex5 4种根尖定位仪测量根尖受破坏牙齿工作长度的准确性.方法 将53颗离体牙沿釉牙骨质界截冠、去髓,根管预备到25#,使用Root ZX(A组),Propex(B组),Justy Ⅱ(C组)和 Raypex5(D组) 4种根尖定位仪分别测量每个根管的工作长度;再使用超声倒预备工作尖将以上各牙沿根尖孔破坏根尖狭窄部,再次用4种根尖定位仪测量工作长度.结果 所得数据与解剖镜下测量的实际数据进行比较,根尖完整时A、B、C、D4组数据在-0.5～0.5 mm误差范围内的百分数分别为86.3%、88.8%、85.0%、88.8%.根尖破坏时A、B、C、D4组数据在-0.5～0.5 mm误差范围内的百分数分别为16.7%、20.5%、10.3%、48.7%,在-1～1 mm误差范围内的百分数分别为74.4%、52.6%、57.7%、91.0%.结论 4种根尖定位仪对于根尖破坏的牙齿测量准确性比根尖完整的牙齿要低,相比之下Raypex5的准确性比较高.     

2种根尖定位仪诊断牙根纵裂的实验研究

目的研究Root ZX和Raypex5根尖定位仪是否能诊断牙根纵裂的存在及其准确位置。方法将20颗离体的双根管单根前磨牙拔髓并扩挫至根尖孔,测量原始根管的实际长度。锤击放置在根管内的根充扩大器柄部使牙根形成纵裂,测量纵裂根管的实际长度,并用Root ZX和Raypex5根尖定位仪测量仅有纵裂线而未完全分裂的纵裂牙根管长度和完全分裂的纵裂牙根管长度,对2种根尖定位仪的根管电测值与实际根管长度进行比较。结果模拟的牙根纵裂均为颊舌向裂,而且裂隙均通过根尖孔。对于仅有纵裂线而未完全分裂的纵裂牙根,Root ZX和Raypex5不能探测到纵裂位置;对于完全分裂的纵裂牙根,Root ZX和Raypex5都能探测到纵裂位置,电测长度在纵裂根管实际长度±1.0 mm范围内分别为97.5%、100%。结论根尖定位仪对仅有纵裂线的牙根纵裂无诊断价值,但对完全纵裂的牙根却有较高的诊断准确性。     

两种电子根尖定位仪测量准确性的实验研究

目的:研究Raypex(5、Root SW两种电子根尖定位仪(electronic apexlocators,EAL)测量准确性。方法:采用琼脂凝胶和单根管离体牙构建EAL体外评价模型,使用两种EAL在同一种电介质中进行根管长度测量,记录测量值(measured length,ML)及测量值和实际值(actual length,AL)之间的差值(IF值)。结果采用Friedman分析。结果:IF值在±0.5mm范围内,Raypex(5为92.5%,Root SW为61.325%;IF值在±1.0mm范围内,Raypex(5为100%,Root SW为87.5%。在本实验中Raypex(5和Root SW测量准确性有显著性差异(P<0.001)。结论:电子根尖定位仪Raypex(5在本实验条件下可以较为准确测量实验牙根管长度。     

根管预备状况对Raypex~5测量准确性的实验研究

目的：研究根管预备状况对Raypex5测量根管工作长度准确性的影响。方法：收集根尖孔发育完成的单根离体牙32个,使用Raypex5分别测量预备前,常规预备,过度预备的根管工作长度。镜下测量实际根管工作长度。将3种电测根管工作长度与实际根管工作长度比较,差值在（0±0.5）mm范围内定为准确。结果：Raypex5测量离体牙预备前,常规预备,过度预备的准确率分别为96.87%、93.75%、87.50%。三者间差异无显著性。电测各组间俩俩比较差异无显著性。结论：在本研究条件下,根管预备对Raypex5测量实验牙根管工作长度准确性无明显影响。     

根管弯曲度对电子根尖定位仪测量准确性的影响

目的： 研究不同弯曲度的根管对Raypex?5、PropexⅡ?和Rider?3种电子根尖定位仪（electronic apex locator,EAL）测量准确性的影响。方法：采用藻酸盐和离体牙构建EAL体外模型,使用Raypex?5、PropexⅡ?和Rider?3种EAL,对123个根管进行根管长度测量,记录测量工作长度值（experimental measurements, EM）及与理论工作长度值（ideal measurements, IAM）之间的差值（IF值）。采用SPSS11.5软件包对数据进行统计学分析。结果：以IAM值±0.5 mm为衡量标准,计算EAL测量直根管、中度和重度弯曲根管的准确率, Raypex?5分别为84.6%、81.6%、87.5%,PropexⅡ?分别为76.9%、89.8%、91.7%,Rider?分别为92.3%、89.8%、87.5%。经检验,各组间IF值无差异显著。结论：根管的弯曲度对根尖定位仪的测量准确性无显著影响,但根管弯曲度不同,不同EAL测量的准确率略有差异。     

根管预备状况对RaypexR5测量准确性的实验研究

目的:研究根管预备状况对Raypex5测量根管工作长度准确性的影响.方法:收集根尖孔发育完成的单根离体牙32个,使用Raypex5分别测量预备前,常规预备,过度预备的根管工作长度.镜下测量实际根管工作长度.将3种电测根管工作长度与实际根管工作长度比较,差值在(0±0.5) mm范围内定为准确.结果:Raypex5测量离体牙预备前,常规预备,过度预备的准确率分别为96.87%、93.75%、87.50%.三者间差异无显著性.电测各组间俩俩比较差异无显著性.结论:在本研究条件下,根管预备对Raypex5测量实验牙根管工作长度准确性无明显影响.     

根尖定位仪Raypex(R) 5测量准确性实验研究

目的:研究根尖定位仪Raypex(R) 5测量特点.方法:采用生理盐水和单根管离体牙构建实验研究模型,使用Raypex(R) 5在离体牙根管内存在0.9%生理盐水时进行根管长度测量,记录测量值和实际值之间的差值(DL)和其分布.对差值数值采用单因素方差分析进行统计学分析.结果:使用第1～3绿色数码条测量准确率在根管真实长度±0.50 mm内分别为55%,65%和70%,DL均值分别为-0.42±0.48 mm,-0.35±0.44 mm和-021±0.41 mm.单因素方差分析显示3组DL值间无显著性差异(P>0.05).结论:结合测量准确率和DL值均值,在本实验条件下Raypex(R) 5第三个绿色显示条对应测量结果最接近根管真实长度.     

根管内血液对根尖定位仪Raypex5测量准确性的影响

目的:通过体外实验评价根管内血液对根尖定位仪Raypex5测量牙齿工作长度准确性的影响.方法:选择单根管离体牙30颗,用直接测量法取得根管实际长度.用生理盐水琼脂模型作为体外测试模型,用Raypex5分别在根管干燥、内有部分血液、充满血液3种情况下测量根管工作长度.结果:直接测量法与电测法数据进行比较,测量值间差异无统...     

Accuracy of different electronic apex locators in determination of minimum Root perforation diameter

This study aims to evaluate the ability of Raypex 6, Propex Pixi, Dentaport ZX, Apex ID, Propex II and Dr.'s Finder NEO to detect minimum root canal perforation diameter. One hundred single-rooted, extracted human teeth were artificially perforated by 5 burs in different diameters (0.25–1.25 mm) in 5 mm above the apex. Twenty teeth were assigned to each group. The actual canal lengths (AL) were measured under stereomicroscope followed by a measurement of electronic canal length (EL) using each electronic apex locator (EAL). None of the EALs were able to detect the perforation at diameters of 0.50 and 0.25 mm. Although all EALs used in our study were unable to detect perforations at diameters of 0.5 mm and 0.25 mm, they were highly successful in the determination of simulated root perforations at diameters of 1.25, 1 and 0.75 mm.     

3种根尖定位仪不同条件下定位根管侧穿孔准确性的体外研究

目的 比较Propex、Raypex(R)5、Root ZX根尖定位仪在不同根管冲洗液中定位根管侧穿孔位置的准确性.方法 选取19颗新鲜拔除的前磨牙,采用ET40超声工作尖破坏根管中下部根管壁,制备根管侧穿孔.使用Propex、Raypex(R)5、Root ZX根尖定位仪定位穿孔位置,比较3种根尖定位仪在不同根管冲洗...     

Evaluation of the Raypex 5 and the Mini Apex Locator: an in vivo study

Introduction

The purpose of this study was to compare the accuracy in vivo of 2 electronic apex locators (EALs), the Raypex 5 and the Mini Apex Locator.

Methods

The working length (WL) was determined electronically for 40 human root canals by using a K-file and 1 of the 2 EALs. The files were fixed at the WL, and the teeth were extracted. The apical 4 mm of each canal was trimmed to expose the file tip. The samples were observed under a scanning electron microscope, and the distance from the file tip to the point 0.5 mm coronal to the major foramen (the final WL) was measured. The data were analyzed by using Student t test, and significance was set at P < .05.

Results

No statistically significant differences were found between the Raypex 5 and the Mini Apex Locator devices. The mean distance from the final WL to the file tip was 0.174 ± 0.38 mm for the Raypex 5 and 0.286 ± 0.30 mm for the Mini Apex Locator. In determining the final WL, the Raypex 5 was accurate 75% of the time to ±0.5 mm and 100% of the time to ±1 mm, whereas the Mini Apex Locator was accurate 77.8% of the time to ±0.5 mm and 100% of the time to ±1 mm.

Conclusions

Under the in vivo conditions of this study, no statistically significant differences were observed between the Raypex 5 and the Mini Apex Locator EALs.     

In vitro evaluation of the accuracy of five different electronic apex locators for determining the working length of endodontically retreated teeth

The aim of this study was to evaluate the accuracy of five electronic apex locators (EALs) in determining the working length (WL) of teeth after removal of the root canal obturation materials. A total of 32 extracted straight, single-rooted teeth were used. The actual canal length (AL) was determined and the WL was established by subtracting 0.5 mm from the AL. The root canals were instrumented and divided into two groups. One group (n = 6) served as control, while the other group (n = 26) was the experimental group. In the experimental group, the root canals were obturated using vertically compacted gutta-percha with AH 26 sealer. In both groups, the access cavities were restored with a provisional restoration and stored for 15 days at 37 degrees C and 100% humidity. The root canal obturation material was removed, and the teeth were then mounted in an experimental apparatus. Five EALs were used: Dentaport ZX, ProPex, Foramatron D10, Apex NRG and Apit 7. For the electronic measurement of canal length, a size 25 K-file was used. During measurement, the canal was irrigated with 2.5% sodium hypochlorite. The difference (D) between the AL and the electronically determined length (EDL), AL-EDL, was calculated and recorded for each measurement. Data were analysed by two-way anova and Fisher's PLSD test. In both groups, statistically significant differences were found among the EALs (P < 0.01). In conclusion, the Dentaport ZX, ProPex and Foramatron D10 were more accurate than the other two EALs in determining the WL in teeth after removal of the root canal obturation materials. However, the Apex NRG and Apit 7 were also reliable for determination of the WL in the majority of the cases.