机用镍钛根管锉折断问题的临床观察

机用镍钛根管锉是新兴的根管预备系统 ,具有柔韧性好 ,塑形能力强 ,能减少术者疲劳 ,提高工作效率等优势。但机用镍钛根管锉折断问题一直困扰着临床医生。我院自 1998年开始在根管治疗中应用机用镍钛根管锉 ,现就其折断问题进行分析 ,报告如下 :材料和方法1.材料　选用HERO64 2     

镍钛根管锉预备弯曲根管的临床疗效

目的：分析评价镍钛根管锉预备弯曲根管的临床效果。方法：随机选择有弯曲根管的患牙髓炎和根尖周炎的前磨牙、磨牙188个，以手用镍钛合金根管锉K型（NiTiflex K）用平衡力技术进行根管预备为实验组。以不锈钢K型锉（stainless stell，K，SS—K）用逐步后退技术预备根管为对照组。两组均侧向加压充填法充填根管。根据治疗前、中、后的X线片评价根管预备和充填的效果。结果：实验组无根管侧穿，台阶形成1例，发生根管偏移仅4例，能较好的维持根管的弯曲度和走向。对照组6例有台阶形成，3例根管侧穿，发生根管偏移的28例明显多于实验组（P〈0．01）。结论：NiTiflexK锉作为一种新型的根管预备器械在弯曲根管预备中显示出独有的优势，能保持弯曲根管良好的根管形态，减少并发症发生，安全有效，实用性强，其临床效果优于不锈钢K型锉。     

手用Protaper镍钛根管锉在根管治疗中的应用研究

目的 了解手用镍钛根管器械ProTaper在根管治疗中的效果.方法 采用随机对照的方法比较手用ProTaper与传统不锈钢根管器械在根管预备时间、根充时间、根管充填的效果以及术后疼痛方面的差异.结果 根管预备时间分别为手用ProTaper组4.58±0.41(min)、不锈钢器械组6.66±0.43(min), 根管充填恰填率为手用ProTaper组80.96%、不锈钢器械组62.64%,术后疼痛的发生率手用ProTaper组3.66%、不锈钢器械组10.26%.结论 手用ProTaper能够保持根管初形、省时省力、术后反应少、安全,值得推广.     

手用镍钛根管锉在后磨牙根管治疗中的临床应用

1材料与方法　1.1病例选择从2004年5月至2005年3月间到我院牙体牙髓科就诊患者的后磨牙,具备以下条件：1）根尖孔已形成;2）根管通畅的牙髓炎、根尖周炎,后磨牙共200颗.随机分为：实验组100颗,其中直根管210根,弯曲根管140根.对照组100颗,其中直根管235根,弯曲根管105根.     

用自凝塑料制取冠桩熔模的临床应用

目前临床上多采用直接法用嵌体蜡条或蜡棒制取桩核的熔模。由于嵌体蜡凝固后变脆 ,以及根外段钢丝的限制 ,熔模很难根据咬合及邻牙关系调整外形 ,尤其是对后牙残根、残冠的操作十分困难。本文介绍一种用自凝塑料制取冠桩熔模的方法 ,能较好地解决上述问题。1　材料与方法1.1　临床资料　 1996年 8月至 2 0 0 1年 3月间 ,用核桩冠修复缺损牙齿 34 2颗。前牙 2 76颗 (中切牙 144颗 ,侧切牙 96颗 ,尖牙 36颗 ) ,后牙 6 6颗 (双尖牙 41颗 ,磨牙 2 5颗 )。核桩材料为钴铬合金 ,冠均为金属烤瓷冠。临床患者 2 2 3人 ,其中男性 10 3人 ,女性 12 0人…     

机用镍钛根管锉逐步深入法处理弯曲细小根管的体会

根管治疗是牙髓病和根尖周病的基本治疗方法 ,过去临床上对弯曲细小根管多采用干髓术或塑化治疗 ,但其成功率低 ,作者采用镍钛根管锉逐步深入法 (ｃｒｏｗｎ -ｄｏｗｎｔｅｃｈｎｉｑｕｅ)对 82例 10 2颗牙 195个根管进行根管治疗 ,现将治疗情况和体会介绍如下。一、资料与方法1.病例 ,选择 2 0 0 0年 10月～ 2 0 0 1年 7月到我科就诊患者 82例 ,其中男性 4 3例 ,女性 39例 ,共 10 2颗牙 195个根管。牙位和根管类型分布情况见表 1,2。表 1　 10 2颗患牙牙位分布情况 (ｎ =牙数 )上颌ｎ下颌ｎ前牙 1前牙 5前磨牙 14前磨牙 7磨牙 3 4磨牙 41总…     

弯曲根管的临床预备要点

弯曲根管的根管预备是根管治疗的难点，直接决定根管治疗的成功率。本文简述了近年来出现的新根管锉系统，保持弯曲根管预备后原有形状的技巧，以及改良的根管预备方法，对弯曲根管的临床预备作一较全面综述。     

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20 g/L的琼脂生理盐水凝胶巾,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最仪的准确性有显著性影响(P＜0.05),最大测量值筹别为0.22 mm.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.     

机用镍钛根管锉预备根管后一次性根充的疗效评价

本文以Profile机用镍钛根管锉采用逐步深入法 (crown downtechnique)预备根管后进行一次性根充 (治疗组 ) ,以手持器械常规法预备根管后进行一次性根充作为对照 (对照组 ) ,经过 2年观察对比其疗效 ,现报告如下。1　资料和方法1.1　一般资料所有病例均选自我院口腔内科门诊就诊的患者 ,以就诊次序编号 ,单号为治疗组 ,双号为对照组 ,各 3 0 0个患牙 ,治疗组 :2 99个牙 (失访 1个牙 ) ;年龄 12～ 72岁 ,男 160例 ,女 13 9例。上颌牙 13 8个 ,下颌牙 161个 ;前牙 84个 ,后牙 2 15个。急性牙髓炎 40个 ,慢性牙髓炎 66个 ,牙髓坏死 5 0个 ,慢性…     

Profile镍钛根管锉在去髓术中的应用体会

目的:评价镍钛根管器械用于去髓术的疗效。方法:选择门诊牙髓炎患者,随机分为两组,分别用Profile镍钛根管锉(实验组)和不锈钢K型锉(对照组)预备根管,然后立即充填,观察两组术后1周内急性临床反应及术后2年的临床疗效。结果:实验组术后1周内临床急性反应明显低于对照组;术后2年疗效两组间无显著性差异。结论:Profile镍钛根管锉预备根管成形能力强,便于根管严密充填,术后急性反应少。     

Flat-oval root canal preparation with self-adjusting file instrument: a micro-computed tomography study

Introduction

The aim of this study was to evaluate the root canal preparation in flat-oval canals treated with either rotary or self-adjusting file (SAF) by using micro-tomography analysis.

Methods

Forty mandibular incisors were scanned before and after root canal instrumentation with rotary instruments (n = 20) or SAF (n = 20). Changes in canal volume, surface area, and cross-sectional geometry were compared with preoperative values. Data were compared by independent sample t test and χ² test between groups and paired sample t test within the group (α = 0.05).

Results

Overall, area, perimeter, roundness, and major and minor diameters revealed no statistical difference between groups (P > .05). In the coronal third, percentage of prepared root canal walls and mean increases of volume and area were significantly higher with SAF (92.0%, 1.44 ± 0.49 mm³, 0.40 ± 0.14 mm², respectively) than rotary instrumentation (62.0%, 0.81 ± 0.45 mm³, 0.23 ± 0.15 mm², respectively) (P < .05). SAF removed dentin layer from all around the canal, whereas rotary instrumentation showed substantial untouched areas.

Conclusions

In the coronal third, mean increases of area and volume of the canal as well as the percentage of prepared walls were significantly higher with SAF than with rotary instrumentation. By using SAF instruments, flat-oval canals were homogenously and circumferentially prepared. The size of the SAF preparation in the apical third of the canal was equivalent to those prepared with #40 rotary file with a 0.02 taper.     

Micro-computed tomography evaluation of the preparation of long oval root canals in mandibular molars with the self-adjusting file

Introduction

The aim of this study was to assess the shaping potential of a novel nickel-titanium instrument, the self-adjusting file (SAF), in long oval root canals in distal roots in mandibular molars.

Methods

Twenty mandibular molars with long oval distal root canals were selected and scanned preoperatively and postoperatively by using micro-computed tomography at an original resolution of 20 μm. Canals were shaped with the SAF, three-dimensionally reconstructed, and evaluated for volume, surface area, canal transportation, and prepared surface. Data were statistically contrasted by using paired t tests and regression analysis.

Results

Preoperatively, canal volume was 7.73 ± 2.13 mm³, and canal area was 42.83 ± 8.14 mm². Volumes and surface areas increased significantly (P < .001) by 4.84 ± 1.73 mm³ and 3.34 ± 1.73 mm², respectively, and no gross preparation errors were detected. Unprepared canal surface varied between individual canals, and mean unprepared surface was 23.5% ± 8.9%. Prepared areas were significantly larger compared with rotary canal preparation done in a previous study. Canal transportation scores were higher in the coronal root canal third (106 ± 50 μm) compared with the apical third (81 ± 49 μm).

Conclusions

In vitro, preparation of long oval-shaped root canals in mandibular molars with the SAF was effective and safe. Moreover, shapes generated with the SAF were more complete compared with rotary canal preparation.     

Time-dependent antibacterial effects of the self-adjusting file used with two sodium hypochlorite concentrations

Introduction

This in vitro study evaluated the time-dependent ability of the self-adjusting file (SAF) used with either of two NaOCl concentrations to reduce bacterial populations in long oval root canals.

Methods

Oval-shaped canals from extracted teeth were infected with Enterococcus faecalis for 30 days and subjected to preparation with the SAF system using continuous irrigation with either 2.5% NaOCl (n = 11) or 6% NaOCl (n = 11). Bacteriological samples were taken before preparation (baseline) and after 2, 4, and 6 minutes of SAF operation.

Results

Intragroup quantitative analyses revealed that the SAF operating for 2, 4, or 6 minutes yielded a highly significant bacterial reduction when compared with counts at baseline (P < .001) irrespective of the NaOCl concentration. No significant differences were found for intragroup analyses comparing the three time periods (P > .05). Likewise, intergroup quantitative analysis showed no significant difference for the SAF with 2.5% NaOCl or 6% NaOCl during 2, 4, or 6 minutes (P > .05). The incidence of positive cultures in the 2.5% NaOCl group was 6 of 11, 5 of 11, and 2 of 11 after 2, 4, and 6 minutes, respectively. Corresponding figures in the 6% NaOCl group were 4 of 11, 2 of 11, and 1 of 11. When all samples were gathered together, overall findings revealed that using the SAF for 6 minutes significantly reduced both the bacterial counts (P = .02) and the incidence of positive cultures (P = .04) when compared with 2 minutes.

Conclusions

Findings revealed that the SAF promoted a significant reduction in bacterial populations even after only 2 minutes regardless of the NaOCl concentration. The most impressive results were obtained after a 6-minute operation.     

三维自调节根管预备锉

镍钛旋转器械预备后的根管横切面为圆形,普遍存在近远中壁过度预备,颊舌侧壁和靠近峡区的泪滴状区域及峡区未被清理等问题,而三维自调节锉（SAF）则可解决上述问题。SAF由中空可压缩的薄镍钛网丝制作而成,不仅在纵向上能顺应根管弯曲方向,在横断面上亦能适应根管形态,自动调整为圆形、扁形或椭圆形等对根管壁牙本质进行均匀的往复式切削。SAF连接冲洗系统VATEA后以持续低压传递冲洗液至根管深处,收到机械预备和化学预备同期进行的效果,有利于去除涂层,遗留的未预备面积较旋转器械少,但其去除根管内感染物质的能力尚存争议：SAF较旋转器械更容易清除椭圆形根管中的细菌,但却不能有效地预备根尖段,冲洗液也难以传递至根尖区域,导致其不能有效去除根管壁碎屑、涂层,亦不能有效地清除根尖的感染细菌。SAF的通畅能力较弱,在再治疗中主要起辅助冲洗的作用,可以去除更多的牙胶残留物。SAF不易出现器械完全分离,偶尔网状镍钛丝的一端分离,另一端仍与器械主体相连,不会出现分离端遗留根管内造成根管堵塞。以SAF联合手用锉预备根管,牙本质壁则几乎无任何微裂纹。简而言之,SAF的出现对于进一步研发和改良器械,提高根管预备效率,减少并发症具有重要的意义。     

Measurements of temperature generated by ultrasonic file in vitro

Abstract The temperature rise of the irrigant in the root canal during free vibration of the ultrasonic file was studied in vitro in 10 human teeth. The mean temperature rise was found to be 0.6°C. The minimal temperature increase may not significantly contribute to the effectiveness of ultrasonic root canal instrumentation.     

两种根管预备器械根管清洁能力的扫描电镜观察

目的 :比较Profile机用根管预备器械与手用K锉预备根管后 ,根管内壁清洁度的差异。方法 :选择 4个无龋、因牙周病而拔除的恒磨牙的弯曲根管 (弯曲度 15°左右 ) ,随机分为两组 ,分别以Profile机用根管器械与手用K锉预备根管 ,预备完成后纵向剖开根管 ,常规制备扫描电镜标本 ,观察比较根管壁的残屑和玷污层。结果 :Profile组根管壁的残屑多为Ⅱ级标准 ,玷污层多为Ⅲ级标准 ;手用K锉组根管壁的残屑多为Ⅲ级标准 ,玷污层多为Ⅲ、Ⅳ级标准。结论 :Profile机用根管预备器械根管清洁能力优于手用K锉。     

两种K型锉预备弯曲人工根管效果的比较

目的 :比较镍钛K型锉和不锈钢K型锉常规法预备弯曲人工根管的切削能力和成形能力。方法 :分别用两种K型锉预备弯曲人工根管 ,电子分析天平称量标本的失重量 ,光学显微镜下观察根管形态变化。结果 :不锈钢K型锉切削能力较强 (P <0 .0 1) ,所有标本未发现根尖拉开、肘部形成和穿孔 ,预备后根尖孔直径镍钛K锉组明显小于不锈钢K锉组 (P <0 .0 0 1)。结论 :镍钛K型锉能保持弯曲根管良好的根管形态 ,而且试尖效果好 ,推荐临床使用     

镍-钛合金机用扩孔钻预备阻塞根管效果

目的：研究镍－钛合金机用扩孔钻预备阻塞根管的效果。方法：临床35例63个各类根管阻塞的患牙，除2牙完全阻塞以外，其余病例均使用镍－钛合金机用扩孔钻预备，结果：治疗过程中患者地不适，X线片显示根管预备完全达到要求，结论：对于各类原因引起的根管阻塞无法进行常规根管扩大的患牙，可以采用镍－钛合金用扩孔钻预备。     

Protaper手用镍钛根管锉预备根管的效果分析

目的 评价Protaper手用镍钛根管锉预备磨牙根管的临床疗效.方法 选患牙髓炎和根尖周炎的恒磨牙252颗,用Protaper手用镍钛根管锉预备根管,侧压法根管充填.记录根管预备时间及器械折断数量.根据治疗前、中、后X线片评价根管预备和充填的效果.结果 Protaper手用镍钛根管锉预备磨牙根管时间短,平均单根管预备时间3.55min,效果好,锥度、流畅度好,术后疼痛少、程度轻,减小根管弯曲度,降低根管预备难度.器械折断9支.结论Protaper手用镍钛根管锉预备根管成形、根充效果好,降低预备时间,提高效率,可明显减小根管弯曲度,降低根管预备难度,但大号完成锉的使用需谨慎.在取根管内充填材料方面有独特的优点.     

The standardized-taper root canal preparation--Part 2. GT file selection and safe handpiece-driven file use

AIM: To present guidelines on GT file selection, and safe operation. SUMMARY: It is not necessary to remove excessive dentine for effective root canal preparation. GT files allow safe, standardized preparation, and should be selected to fit the case in hand. Small Root canals should be prepared with 0.06 and 0.08 taper GT files, whilst Large Root canals should be prepared with 0.10 GT or 0.12 Accessory GT files. The greatest challenge is un-learning habits acquired from traditional instrumentation methods. GT files should be used with light touch, and without up-down pumping motions. Spin speeds should be controlled below 300 r.p.m. for routine preparation. GT files are subject to fatigue and should be tracked to avoid overuse. It is recommended that GT files are discarded after the equivalent of five root canal preparations. For severe curvatures, GT files should be single-case tools. KEY LEARNING POINTS: The standard GT file set comprises three instruments of 0.06, 0.08 and 0.10 taper. All are size 20 at the tip, and have a maximum diameter of 1 mm. Accessory GT files have a standard taper 0.12, and maximum diameter of 1.5 mm. They are available in tip sizes 35, 50 and 70. Large Roots are lower canines, upper anteriors, upper and lower single-rooted premolars, palatal roots of upper molars and distal roots of lower molars. They should be prepared with 0.10 GT or 0.12 Accessory GT files. Small Roots are lower incisors, multirooted premolars, buccal roots of upper molars and mesial roots of lower molars. They should be prepared with 0.06 or 0.08 GT files. All GT files should be used with light force and at the correct spin speed. GT files should be discarded after the equivalent of five root canal uses.