Root canal filling of endodontically treated teeth by dentistry students in clinical offices from 1996 to 1998--radiological results

THE PURPOSE of our study was to evaluate radiologically the degree of root canal filling of teeth treated by students. METHODS: 724 segment radiographs with an overall number of 1142 canals were examined. The level of root canal filling was measured from the radiographic apex. The objects of the study were divided into three groups: 1. canals filled to more than 2 mm from the apex; 2. canals filled up to 2 mm from the apex; 3. canals filled to the radiographic apex; 4. overfilled canals. The objects from the second and the third group were combined as a group of successfully filled canals. RESULTS: The results showed 62.90% of successfully filled canals, 27.80% of the canals were filled more than 2 mm from the radiological apex and 9.30% - with overfilling. The greatest percentage of canals filled more than 2 mm from the apex refers to the mesial and vestibular canals of the molars, and after them the most frequently obturated canals are those of single-root teeth (57.94%). CONCLUSIONS: The results obtained allow us to estimate the endodontic treatment of the students as good. The greatest difficulties are encountered in filling the vestibular and mesial canals of the molars.     

Propex根管测量仪对急性根尖周炎患牙工作长度测量的评价

目的:评价急性根尖周炎患牙根管工作长度测量中应用Propex根管测量仪的准确性。方法:220例急性根尖周炎患者,276颗患牙512个根管,随机分为两组,对照组摄X线牙片观察并测量根管工作长度;实验组采用ProPex根管测量仪测量根管工作长度。结果:对照组和实验组工作长度准确率分别为77.5%、91.5%,两组准确率的差异有统计学意义(P0.05)。结论:ProPex可以比较准确地测量急性根尖周炎患牙的工作长度。     

两种根管长度电测仪的准确率比较

目的:评价两种根管长度电测仪的准确率。方法:选择60颗单根管下颌第一前磨牙,分别用Root ZX和ProPex根管电测仪测量根管工作长度。然后拔除牙齿,用细金刚砂车针沿牙根尖1/3纵轴方向磨出剖面,显露根尖狭窄处,在牙科手术显微镜下用游标卡尺测量根管工作长度。用电测仪测量值减去游标卡尺测量值,准确率范围限定在±1.0mm。结果:Root ZX根尖电测仪准确率为90%,ProPex根管测量仪准确率为93.3%,两者差异无统计学意义(P0.05)。两种电测仪测量的工作长度均未超出根尖孔。结论:Root ZX和ProPex根管测量仪均是较理想的测量仪,两者均能较准确的确定根管的工作长度。     

应用锥形束CT评估上颌中切牙髓腔增龄变化的研究

目的利用锥形束CT(CBCT)测量上颌中切牙髓腔的长度和直径,为临床桩核设计提供依据。方法 76名患者100颗上颌中切牙按照年龄分为5组,A组15²4岁,B组2524岁,B组25³4岁,C组3534岁,C组35⁴4岁,D组4544岁,D组45⁵4岁,E组5554岁,E组55⁶5岁。用锥形束CT进行扫描,分析上颌中切牙髓腔长度及釉牙骨质界处、根中1/2、距根尖4 mm处髓腔宽度。结果采用t检验和拉丁方进行数据比较,髓腔长度随着年龄增长没有出现显著性差异(p>0.05),釉牙骨质界处、根尖1/2、距根尖4 mm处髓腔宽度随着年龄增长有显著性差异(p<0.05),宽度逐渐变窄。结论髓腔宽度随着年龄增长逐渐变窄,髓腔长度与年龄的关系不明显。CBCT能精确测量髓腔的长度和宽度,按桩道制备的要求进行合理的分析设计。     

四手操作对根管预备中辅助设备的使用效果与保养的意义

目的探讨四手操作在根管预备中辅助设备使用与保养的意义。方法回顾分析、总结628例在根管预备过程中电子根尖定位仪、机用镍钛器械、超声根管治疗仪和牙科显微镜辅助设备的合理使用和正确保养的临床资料。结果 628例根管预备治疗获得满意的效果,上述辅助设备功能正常、保养良好。结论四手操作在根管预备中辅助设备的合理使用和正确保养方面起到积极作用,可延长辅助设备的使用寿命、减少因设备原因造成的并发症。     

Analysis of stresses in hard dental tissues generated by clinical application of retentive root canal posts

INTRODUCTION: Exact adjustment of retentive posts to the length of root canals is an important prerequisite for the effectiveness of post systems. AIM: To determine stresses generated in hard dental tissues of upper and lower canines by the application of root canal posts. MATERIAL AND METHODS: The finite element method was used to create models of upper and lower canines. Loading by a vertical force of Pw = 24 N and a horizontal force of Pv = 15 N was investigated. Twenty two partial dentures and total overdentures in 17 patients were constructed and retained by devices for intraroot retention, placed in canine roots. 16 upper and lower canines were restored by steel posts and composite resin cores. RESULTS AND DISCUSSION: Equivalent stresses were the greatest at the opening of the root canal. Their maximal values during horizontal loading (6.2 - 6.8 MPa) were several times as high as the values during vertical loading (1.0 - 1.1 MPa). The maximal equivalent stresses were in the range of 20 - 25 MPa, when the diameter of the root canal was 1.5 x 10(-3) mm smaller than the diameter of the post. CONCLUSIONS: Stresses generated in canine roots with retentive posts during horizontal loading are greater than the stresses induced by vertical loading. Attempts for forceful placement of posts in insufficiently enlarged root canals produce stresses of considerable magnitude which could result in cracks and fractures of hard dental tissues.     

Evaluation of the accuracy of electronic apex locators Dentaport ZX and Ray Pex 4 under clinical conditions

AIM: The aim of the present study was to compare the accuracy of working endodontic length determination by Dentaport ZX and Ray Pex 4 under clinical conditions. MATERIAL AND METHODS: Clinical comparative evaluation of the accuracy of two electronic apex locators, Dentaport ZX and Ray-Pex 4, was carried out in 80 single-rooted teeth with vital pulp tissue planned for extraction as part of the dental treatment and after patient consent had been obtained. The normal procedure was followed, which included anesthesia, a standard endodontic access cavity, pulp removal and irrigation of the root canal with 5.25% NaOCl. The working length was estimated with Dentaport ZX for half of the selected teeth and with Ray-Pex 4 for the other half. K-files #15 were cemented at the measured working length and the teeth were extracted. The apical foramen was examined with a stereomicroscope under x15 magnification. The micrometric system of the microscope allowed precise measurement of distances. RESULTS: The comparison of the estimated working length with the actual length revealed that Dentaport ZX localized the apical foramen in 95% of the cases and the Ray Pex 4 in 92.5% with a clinically acceptable accuracy of +/- 0.5 mm. Dentaport ZX detected the foramen in 97.5% and Ray Pex 4 in 95% of the cases with an accuracy of +/- 1 mm. There was no statistically significant difference between the accuracy of the two electronic apex locators in locating the apical foramen (p < 0.05).     

Vitapex诱导年轻恒牙根尖形成的临床疗效观察

目的观察Vitapex糊剂在根尖诱导形成术中的疗效。方法随机选择门诊52例根尖未发育完成的牙髓坏死年轻恒牙。根管预备,消毒后用Vitapex糊剂进行根尖诱导,观察1年。结果成功27例（51．92％）,显效21例（40．38％）,失败4例（7．69％）,总有效48例（92．31％）。结论Vitapex糊剂是一种有效的根尖诱导剂。     

Comparative evaluation of cone-beam CT equipment with micro-CT in the visualization of root canal system

The aim of this study was to compare three different cone-beam CT (CBCT) instruments used in dental clinical practice with micro-CT as gold standard. Three female monkeys' (Macaca fascicularis) skulls were selected and scanned by the tested CBCT-s. The most apical visible root canal level on the CBCT images was used as reference level (RL). After the image acquisition by CBCT-s dental jaw sections were scanned by micro-CT at a resolution of 17 μm. Out of the left second and third molars 25 root canals were selected and analysed by three observers at RL and following cross sectional parameters were determined: area of the lumen, major and minor diameters, aspect ratio and mean thickness. Results suggest that only high resolution CBCT instruments allow dentists detecting the full length of the root canal.     

Joint Discussion No. 8: Sections of Odontology,Electro-Therapeutics,and Pathology: DISCUSSION ON THE PULPLESS TOOTH

A large proportion of the population have pulpless teeth, hence the importance of this subject. The main principles concerned in the treatment of pulpless teeth are: the removal of the pulp in its entirety, the drainage of the stump of the severed pulp, the cleansing and drying of the root canals and the filling of the tooth cavity.Local anæsthesia is preferable to caustics for desensitizing the tooth pulp prior to its removal. Antiseptics used in a dry condition are preferable to those used in a moist condition for root canal treatment.Nothing is gained by filling the root canals, if the peri-apical tissues have scarred there is no further discharge into these canals; and if they have not scarred the filling of the root canals will only obstruct drainage. If the discharge from the canals is copious, the tooth cavity should be left open to the mouth except for the insertion of a loosely placed dressing.Untreated pulpless teeth are more liable to give rise to “open” sepsis; treated pulpless teeth to “closed” sepsis.The crux of the question as to whether pulpless teeth should be retained or extracted is one of evaluating their advantages and disadvantages.A tooth deprived of its pulp owing to infective changes gives rise to subjective and objective symptoms and signs.A tooth deprived of its pulp owing to physiological changes gives rise to no apparent ill effects.     

四手操作在现代根管治疗术中的护理配合

目的探讨现代根管治疗中"四手操作"的护理配合要点。方法180例患牙髓炎或根尖周炎的患者在根管治疗过程中采用四手操作,护理配合包括安排患者、准备治疗用品、调配材料、传递和回收器械、及时吸除口内唾液、水和废屑,利用X光片初步测量根管长度,根管预备、消毒,充填的护理。结果所有患牙经根管治疗后X线片显示为恰充,无严重术后并发症。结论四手操作要求护士必须具备丰富的专业知识,熟悉专科器械的性能和使用方法,熟悉每一步操作程序,才能极大地提高医疗质量和工作效率,缩短患者的诊疗时间,促进和谐的医患关系。     

Vitapex诱导年轻恒牙根尖形成的临床疗效观察

目的观察Vitapex糊剂在根尖诱导形成术中的疗效。方法随机选择门诊52例根尖未发育完成的牙髓坏死年轻恒牙。根管预备,消毒后用Vitapex糊剂进行根尖诱导,观察1年。结果成功27例(51.92%),显效21例(40.38%),失败4例(7.69%),总有效48例(92.31%)。结论 Vitapex糊剂是一种有效的根尖诱导剂。     

四手操作在现代根管治疗术中的护理配合

目的探讨现代根管治疗中“四手操作”的护理配合要点。方法180例患牙髓炎或根尖周炎的患者在根管治疗过程中采用四手操作，护理配合包括安排患者、准备治疗用品、调配材料、传递和回收器械、及时吸除口内唾液、水和废屑，利用X光片初步测量根管长度，根管预备、消毒，充填的护理。结果所有患牙经根管治疗后X线片显示为恰充，无严重术后并发症。结论四手操作要求护士必须具备丰富的专业知识，熟悉专科器械的性能和使用方法，熟悉每一步操作程序，才能极大地提高医疗质量和工作效率，缩短患者的诊疗时间，促进和谐的医患关系。     

Present and future in the use of micro-CT scanner 3D analysis for the study of dental and root canal morphology

The goal of the present article is to illustrate and analyze the applications and the potential of microcomputed tomography (micro-CT) in the analysis of tooth anatomy and root canal morphology. The authors performed a micro-CT analysis of the following different teeth: maxillary first molars with a second canal in the mesiobuccal (MB) root, mandibular first molars with complex anatomy in the mesial root, premolars with single and double roots and with complicated apical anatomy. The hardware device used in this study was a desktop X-ray microfocus CT scanner (SkyScan 1072, SkyScan bvba, Aartselaar, Belgium). A specific software ResolveRT Amira (Visage Imaging) was used for the 3D analysis and imaging. The authors obtained three-dimensional images from 15 teeth. It was possible to precisely visualize and analyze external and internal anatomy of teeth, showing the finest details. Among the 5 upper molars analyzed, in three cases, the MB canals joined into one canal, while in the other two molars the two mesial canals were separate. Among the lower molars two of the five samples exhibited a single canal in the mesial root, which had a broad, flat appearance in a mesiodistal dimension. In the five premolar teeth, the canals were independent; however, the apical delta and ramifications of the root canals were quite complex. Micro-CT offers a simple and reproducible technique for 3D noninvasive assessment of the anatomy of root canal systems.     

全自动根管治疗机测定牙齿根管长度的准确性比较

目的：评价SM—TR-ZX全自动根管治疗机测定牙齿操作长度的准确性;方法：分别用器械探查法、X线照片法、SM—TR-ZX全自动根管治疗机电测法对需要进行根管治疗术的295个根管进行三者比较;结果：SM—TR—ZX全自动根管治疗机电测法的准确性明显高于器械探查法和X线照片法（p〈0．01）;结论：SM—TR—ZX全自动根管治疗机测定根管长度的准确性较高。     

三种根管工作长度测量法精确性的临床评价

目的：观察和探讨手感法、摄片法和电测法测定根管工作长度的精确性。方法：选择慢性根尖周炎、牙周病、残根残冠等毫无保留价值的患牙及正畸需拔的健康牙，共20颗牙30个根管，分别用手感法、摄片法和电子根测仪Root ZX测量各根管的工作长度，将拔牙后直视下测得的根管长度作为诊断标准，与各种方法所测得的值进行比较，以确定其准确率。结果：手感法的准确率为33．33％，摄片法为43．33％，电测法为80．00％，手感法与摄片法比较无统计学意义（P〉0．05），RootZX法与手感法比较有统计学意义（P〈0．01），RootZX法与摄片法比较有统计学意义（P〈0．01）。结论：电子根尖定位仪测定根管工作长度的准确率比摄片法和手感法高，临床应结合使用可提高准确率。     

锥形束CT辅助诊断上颌第二磨牙3根5根管一例

上颌第二磨牙根管系统复杂,容易出现根管数目或位置形态的变异,同时由于操作视野的局限,容易遗漏根管从而导致根管治疗失败.锥形束CT(CBCT)可辅助上颌第二磨牙多根管的发现、定位及治疗,避免多根管复杂牙根管的遗漏,提高上颌第二磨牙根管治疗的成功率.该研究在开髓后发现髓底结构复杂,采用CBCT辅助发现及定位根管,明确了患牙...     

Vitapex糊剂在感染性牙根管患者治疗中的应用价值

目的 探讨Vitapex糊剂在感染性牙根管患者治疗中的应用价值。方法 本研究回顾分析本院口腔科2013年1月至2017年6月收治200例感染性牙根管患者的临床资料,随机将其分为对照组和实验组,对照组接受氧化锌丁香油糊剂治疗,实验组接受Vitapex糊剂治疗,比较分析2组患者临床治疗效果。结果 实验组根管填充欠填率为2%,超填率为42%,3个月后超填吸收率为90.5%,6个月后总有效率为94%;对照组观察对象根管填充欠填率为9%,超填率为28%,3个月后超填吸收率为67.9%,6个月后总有效率为80%,2组比较差异有统计学意义(P<0.05)。结论 在感染性牙根管患者治疗中应用Vitapex糊剂,具有较为理想的填充效果,且治疗有效率较高,因而值得推广和应用。     

新型根管治疗灭菌器的研制与开发

目的研制开发一种适合对根管治疗小器械快速灭菌的灭菌器。方法仿照日本SL灭菌器的工作原理制造出新型根管治疗灭菌器,检测其升温情况,用细菌培养法检测其灭菌效果,并与高温高压消毒效果进行比较。结果新型根管治疗灭菌器接通电源208.8 s可以达到设定温度(285±3)℃,7 s的灭菌效果与高温高压(Eurouda灭菌器E6-18/24)无区别。结论新型根管治疗灭菌器消毒灭菌效果可靠。     

半导体激光照射预防和缓解牙髓炎急性反应

目的观察半导体激光照射预防及缓解根管治疗急性反应（endodontic interappointment EIAE）的效果。方法选取需进行根管治疗的患有牙髓炎及根尖周炎的牙病患者304例，随机分为2组，在进行根管预备及樟脑酚棉捻开放后，其中1组（155例）应用半导体激光在牙体外辐射根尖区，另1组不作处置，24h后观察记录患者主观症状和体征，比较2组根管治疗急性反应发生率。另选取根管充填后发生急性反应的牙病患者175例，随机分为2组，1组（96例）应用半导体激光在牙体外辐射根尖区；另1组（79例）给予口服甲硝唑及先锋Ⅳ，24h后观察记录患者主观症状和体征，比较2组缓解根管治疗急性反应效果。结果304例牙病患者中，应用半导体激光照射组的急性反应发生率为4．52％，未照射组为10．74％，2组差异有统计学意义（P〈0．05）；175例根管填充后发生急性反应的患者中，半导体激光照射组的EIAE缓解效果明显好于药物治疗组，2组差异有统计学意义（P〈0．05）。结论半导体激光照射可有效预防和缓解根管治疗急性反应。