不同角度根尖片对诊断下颌第一前磨牙多根管的作用

目的探讨联合应用平行和偏移投照根尖片在诊断下颌第一前磨牙多根管中的作用。方法选择临床上需要进行根管治疗的130人的132颗下颌第一前磨牙为研究对象,每颗患牙术前均需拍摄平行和偏移投照X线片,初步判断是否为多根管牙;术中配合使用根管显微镜用K锉探寻根管口及根管,使用手用镍钛锉进行根管预备,侧方加压技术充填根管。结果132颗下颌第一前磨牙中,术前平行和偏移投照x线片共初步诊断多根管牙41颗;平行投照诊断多根管牙16颗,偏移投照诊断多根管牙37颗,其中有12颗患牙2种投照方法均表现为多根管影像。两种投照方法诊断的下颌第一前磨牙多根管与在临床治疗中发现的多根管数一致,发现率为31．06％。结论平行和偏移投照X线片联合应用有助于提高下颌第一前磨牙多根管的发现率,从而减少临床遗漏根管的发生。     

不同投照角度X线根尖片诊断下颌前牙、前磨牙多根管的临床评价

目的 探讨不同角度X线投照技术对发现下颌前牙、前磨牙多根管及提高其临床治疗率的作用。方法 选取临床上需要进行下颌前牙、前磨牙根管治疗的患者214例，共247颗患牙。每颗患牙均需拍摄术前X线正、偏位投照片及诊断丝X线正、偏位投照片。依据两种X线影像特点（根管位置和走向不在牙根中心、较粗大的根管在根管上1／3、中1／3突然消失或模糊）判断是否为可疑多根管。采用冠向下法预备，冷侧压法根管充填后将根管分为Ⅰ～Ⅴ型并与X线结果对应。结果 在87颗X线诊断的多根管患牙中，临床证实多根管为60．92％；26．44％为扁根管。诊断丝X线偏位投照片的多根管X线诊断灵敏度为93．0％，4例术后发现有遗漏根管。247颗下颌前牙、前磨牙临床治疗多根管57颗，多根管临床治疗率分别为：中切牙9．43％、侧切牙38．33％、尖牙15．90％、第一前磨牙加．38％、第二前磨牙2．63％。结论 不同角度的术前及诊断丝X线根尖片有助于临床医师发现下颌前牙、前磨牙多根管，其中以诊断丝X线偏位投照发现的多根管最多。     

多根管下颌前磨牙显微根管治疗的效果观察

目的观察下颌前磨牙多根管的发现率以及显微根管治疗方法处理多根管下颌前磨牙的临床疗效。方法选取152颗需进行根管治疗的下颌前磨牙，拍摄术前X线正位投照片和偏位投照片。对单根管患牙采用常规根管治疗，对怀疑多根管的患牙先常规探查根管，再在显微镜下探查并疏通根管，镍钛机动器械预备根管，垂直加压充填技术充填根管。记录根管类型，使用和未使用显微镜时多根管的发现率，根据术前、术中及术后X线片评价根管预备和充填效果。结果下颌第一前磨牙、第二前磨牙多根管的发现率分别为32．9％、7．5％；使用显微镜多根管的发现率高于未使用显微镜者；治疗中无根管堵塞、偏移、台阶、器械折断等并发症发生，完成治疗的31颗多根管下颌前磨牙30颗适充，1颗超充。结论显微根管治疗是处理多根管下颌前磨牙的有效方法。     

下颌前磨牙C形根管的诊断和治疗

目的：探讨下颌前磨牙C形根管的发现率及其诊治方法。方法：选取需要根管治疗的下颌前磨牙300个,拍摄术前正位和偏位X线牙片。多根管牙插诊断丝摄片。结合C形根管的诊断标准,诊断为C形根管的忠牙,记录髓室底形态和X线影像类型。所有患牙使用镍钛机动根管器械预备,侧方加压法充填根管。根据术前、术中和术后x线片评价根管预备和充填效果。结果：第一和第二前磨牙C形根管的发现率依次为5．56％和2．50％。髓室底以C2型多见,X线影像以尖部融合型多见。治疗中无根管堵塞等并发症的发生。根管充填效果,13例C形根管中有5例超充,8例恰充。结论：髓腔探察和插诊断丝拍片是诊断下颌前磨牙C形根管的有效方法。     

下颌切牙双根管的显微根管治疗

目的评价显微根管治疗术处理下颌切牙双根管的临床疗效。方法选取143颗需进行根管治疗的下颌切牙（下颌中切牙68颗,下颌侧切牙75颗）,拍摄术前X线正位投照片和偏位投照片。对单根管患牙采用常规根管治疗;对疑为双根管的患牙先常规探查根管,再在牙科手术显微镜下探查并疏通根管,机用镍钛器械预备根管,垂直加压充填技术充填根管。记录根管类型,不同X线投照角度、使用和未使用牙科手术显微镜时多根管的发现率,根据术前、术中及术后X线片评价根管预备和充填效果。结果采用显微根管治疗,下颌中切牙、侧切牙双根管的发现率分别为26.47%、29.33%,X线偏位投照片双根管的发现率高于正位投照片;使用牙科手术显微镜后,多根管的发现率高于未使用时;在牙科手术显微镜下进行根管预备,无根管堵塞、偏移、台阶、器械分离等并发症发生;134颗患牙适充,9颗有糊剂或牙胶超充,无欠充。结论显微根管治疗是处理双根管下颌切牙的有效方法,在牙科手术显微镜下以机用镍钛器械预备根管,垂直加压充填技术充填根管可取得良好的治疗效果。     

X线投照角度对判断后牙颊舌向多根管的作用

目的探讨X线投照角度在判断多根管磨牙根管充填效果时的作用。方法选取存在近颊第二根管的上颌第一磨牙87颗、下颌第一磨牙105颗，拍摄术前X线片，完成根管治疗，术后分别拍摄X线正位投照片和远中偏位投照片，判断根充效果。结果X线正位投照片和远中偏位投照片能显示上颌第一磨牙MB与MB2的比例分别为23．0％和81．6％，显示下颌第一磨牙近中两根管的比例分别为38．1％和90．5％，X线远中偏位投照片显示颊、舌向根管的比例大于正位投照片（P〈0．005）。结论采用X线远中偏位投照法能更好地显示上、下颌第一磨牙颊舌向根管的充填效果。     

偏移投照技术与显微治疗诊治遗漏根管的疗效分析

目的分析根管治疗术后偏移投照技术与显微根管治疗的应用对遗漏根管的发现与治疗的临床疗效。方法选择需行初次牙髓治疗的下颌前牙、下颌前磨牙、下颌第一、二磨牙及上颌第一、二磨牙共360颗(分别为49、68、62、50、85、46颗)。常规拍摄术前正位根尖片,并于根治后拍摄正位及20°～30°偏位根尖片,通过对比分析,对可疑遗漏根管的患牙,在显微镜下寻找及治疗遗漏根管。结果经显微治疗,360颗患牙中25颗(6.9%)确诊为遗漏根管,各牙位依次为3、5、5、4、6、2颗,其中23颗患牙发现并成功充填遗漏根管,2颗根管可找到但不完全通畅;正位发现8颗(2.2%),偏位发现23颗(6.4%),术后偏移投照发现率明显高于正位(P<0.05)。结论根治术后偏移投照技术与显微根管治疗对遗漏根管的发现与治疗有较大的帮助。     

下颌第一前磨牙根管的临床显微观察

目的比较肉眼和根管显微镜探查对下颌第一前磨牙多根管的发现情况，为推广根管显微镜的临床应用提供参考依据。方法选取80颗需要根管治疗的下颌第一前磨牙，开髓后先行肉眼探查：插诊断丝拍正位、偏位X线片，结合髓底图和X线片对根管数目做出判断。再采用根管显微镜，观察并记录各牙的根管数目、类型。比较2种方法对下颌第一前磨牙多根管的发现情况。结果肉眼探查结合插针拍片法和根管显微镜探查多根管发现率分别为12．5％和30．0％，准确率分别为38．46％和92．31％，发现率和准确率的差异均有统计学意义（P〈0．001）。结论根管显微镜探查法能够较为准确地判断下颁第一前磨牙的根管数目和类型。     

Clinical evaluation of different angulation radiograph in diagnosing distolingual root of the mandibular first molar

目的 评价不同投照角度X线根尖片诊断下颌第一磨牙远中舌根的作用.方法 选择需行根管治疗的205颗下颌第一磨牙为研究对象.术前拍X线正位根尖片及近中20°～30°偏位根尖片,对比分析是否存在远中舌根.术中根据根管的弯曲情况把远中舌根分为3类.记录下颌第一磨牙牙根和根管的数量.结果 术前X线正位、近中偏位根尖片判断48颗(48/205)下颌第一磨牙存在远中舌根,临床治疗中均确定有远中舌根,其余157颗下颌第一磨牙术中均未见远中舌根.远中舌根发生率为23.41%.48颗下颌第一磨牙远中舌根中,Ⅰ类根管22颗(45.83%);Ⅱ类根管17颗(35.41%);Ⅲ类根管9颗(18.75%).205颗下颌第一磨牙106颗(51.70%)为3根管;98颗(47.80%)为4根管;1颗(0.48%)为5根管.结论 术前多角度根尖片能准确诊断下颌第一磨牙远中舌根.     

不同投照角度X线根尖片诊断下颌第一磨牙远中舌根的临床研究

目的评价不同投照角度X线根尖片诊断下颌第一磨牙远中舌根的作用。方法选择需行根管治疗的205颗下颌第一磨牙为研究对象。术前拍X线正位根尖片及近中20°～30°偏位根尖片,对比分析是否存在远中舌根。术中根据根管的弯曲情况把远中舌根分为3类。记录下颌第一磨牙牙根和根管的数量。结果术前X线正位、近中偏位根尖片判断48颗(48/205)下颌第一磨牙存在远中舌根,临床治疗中均确定有远中舌根,其余157颗下颌第一磨牙术中均未见远中舌根。远中舌根发生率为23.41%。48颗下颌第一磨牙远中舌根中,Ⅰ类根管22颗(45.83%);Ⅱ类根管17颗(35.41%);Ⅲ类根管9颗(18.75%)。205颗下颌第一磨牙106颗(51.70%)为3根管;98颗(47.80%)为4根管;1颗(0.48%)为5根管。结论术前多角度根尖片能准确诊断下颌第一磨牙远中舌根。     

Analysis of radiologic factors in determining premolar root canal systems

OBJECTIVES: Certain tooth groups pose problems as to radiologic determination of root canal morphology. For example, the premolars may have superimposed roots that give the appearance of a single canal when 2 are actually present. This study examined the effect of X-ray tube inclination so as to visualize the complete root canal system in premolars. STUDY DESIGN: One hundred extracted premolars were divided into 4 groups of 25 teeth each: 1MxP (first maxillary premolar), 2MxP (second maxillary premolar), 1MdP (first mandibular premolar), and 2MdP (second mandibular premolar). A total of 10 radiographs were made of each tooth in the horizontal and vertical planes (horizontal angles of 0, 20, and 40 degrees, then vertical angles of 0, 15, and 30 degrees). Logistic regression analysis was used for the statistical analysis of the results--the dependent variable being the number of canals visualized. RESULTS: On varying the horizontal angle (20 and 40 degrees), the number of root canals observed in the case of 1MxP, 2MxP, and 1MdP coincided with the actual number of canals present. In the case of 2MdP, only the 40 degree horizontal angle correctly identified the number of canals regardless of the vertical angle (although only 4% had more than 1 canal). CONCLUSIONS: Varying the horizontal angle improved the visualization of additional (superimposed) canals in premolars. Changing of the vertical angle had no statistically significant influence except for the first mandibular premolars.     

Mandibular premolar with three root canals—two case reports

The presence of three root canals in the mandibular premolar may sometimes be recognized when there is persistent postoperative discomfort following root canal therapy. This paper presents two cases of root canal treatment of mandibular premolars with three root canals including one mandibular first premolar and one mandibular second premolar. The possibility that there is more than one root canal in lower premolar teeth must be considered in the radiographic and clinical examination during root canal treatment.     

Diagnosis and root canal treatment of a mandibular second premolar with three root canals

AIM: To present a case of a mandibular second premolar with three root canals. SUMMARY: An accurate diagnosis of the morphology of the root canal system is a prerequisite for successful root canal treatment. A review of the literature reveals a low incidence of all types of premolars with three root canals. Diagnostic means such as preoperative radiographs and examination of the pulp chamber floor aid the location of root canal orifices. The diagnostic and therapeutic problems concerning premolars with unusual anatomy are described on the basis of a clinical example. A case report describes the successful treatment of a mandibular second premolar with three root canals. KEY LEARNING POINTS: Clinicians should be aware of unusual root canal anatomy in mandibular premolars. Radiographs exposed at two different horizontal angles and their careful interpretation facilitate the search of additional root canals. The use of magnification and additional lighting are recommended for the clinical examination of the pulpal floor.     

Radiographic evaluation of root canal multiplicity in mandibular first premolars

The purpose of this study was to examine the accuracy of radiographic evaluation of root canal multiplicity in mandibular first premolars in vitro. One hundred thirty-nine extracted human mandibular premolars were used. Buccolingual radiographs were taken, and the number of canals in each tooth was determined on radiographs by four dentists using a view box. A sudden narrowing of the main canal was interpreted as a sign of multiple canals. After the radiographic evaluation, the tooth crown was removed. India ink was injected into the root canal system, and the root was cleared to observe the canal morphology. There was no statistically significant difference among the four dentists with respect to the coincidence rate (93%-96%) of the canal number evaluated on radiographs with that identified by cleared teeth observation (p > 0.05, one-way analysis of variance). A sudden narrowing of the main canal on the radiograph was a good criterion to judge root canal multiplicity.     

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??Objective    To investigate the effect of different angle of digital X-ray on detective rate of multiple canals in mandibular first premolar in order to find the best angle. Methods    Totally 46 mandibular first premolars were collected??white wax dental models with mandibular first premolar were fabricated??digital X-ray films for each first premolar were taken from orthotopic??mesio-clination ??10??20°??and distal-clination??10??20°??. All films were evaluated and compared with the results of operation microscope??OM??observation under 8 fold eyesight??whose roots were cross sected from root cervical??mid and apical part. The root canal numbers of each cross section were recorded as gold standard. SPSS13.0 software was employed and consistency test of each projection angles with gold standard was analyzed. Results    For mandibular first premolar??at mesial or distal projection of 20°??consistency of detective rate of multiple canals was better. Sensitivity at mesial projection of 20°was the highest. Conclusion    Mesial projection of 20° for mandibular first premolar is the optimal angle in detecting multi-canals.     

Root canal treatment of mandibular second premolar with four root canals: a case report

The importance of an accurate diagnosis of the morphology of the root canal system is a prerequisite for successful root canal treatment and has been emphasized throughout the literature. Root canal morphology of premolar teeth, either maxillary or mandibular, and the discrepancies between first and second premolars, have been investigated and reported. A case report is presented of the root canal treatment of a mandibular second premolar with four root canals. As far as the reviewed literature revealed, up to three root canals in mandibular premolars have been reported. No previous report of a similar case of four root canals in a mandibular premolar was found.     

Morphological variations of mandibular first premolar on cone-beam computed tomography in a Saudi Arabian sub-population

In-depth knowledge of common and aberrant pulp morphology is essential for appropriate diagnosis and treatment planning prior to commencing root canal treatment. Radicular morphology of mandibular premolars has been extensively studied. Considerable variation in the number of canals and roots found in these teeth has been reported.AimThe purpose of this study is to investigate the root and root canal morphology of mandibular first premolar among Saudi Arabian subpopulation in Aseer using CBCT.MethodsCone-beam computed tomography images of Mandibular first premolar were taken from 166 patients which were referred to Armed Forces Hospitals Southern Region (AFHSR), Khamis Mushayt, Asir region Saudi Arabia. All the images were assessed by two Evaluators (An Endodontist and a Radiologist). Inter-examiner reliability was determined and was assessed by KAPPA value.ResultsThe mandibular first premolar (n = 216) distributed as 120 teeth in female and 96 teeth in male. Out of the 120 teeth examined in female groups one canal was seen in 95 (79.2%) teeth, two canals in 19 (15.8%) teeth and three canals in 6 (5%) teeth where as in the Male group out of 96 teeth, 52 (54.1%) teeth showed one canal, 32 (33.3%) teeth with two canals whereas 12 (12.5%) teeth showed presence of three canals.Chi-Square test for mandibular first premolars demonstrated the chance of second canal in the mandibular first premolar more in male than female and these differences was statistically significant (P ≤ 0.05).ConclusionEndodontic therapy of mandibular premolars is a challenge for clinician because of their frequent morphological and anatomical abnormalities. Proper knowledge about number of root canals and canal configuration is a key to success in Endodontic. There is a great variability in different population regarding the root canal configuration in mandibular pre-molars. However, most studies state the mandibular first premolar has one root canal. Also, the most prevalent type of root canal found was Type I vertucci.