Root form and canal morphology of mandibular premolars in a Jordanian population

AIM: To investigate the root canal anatomy of mandibular premolars in a Jordanian population. METHODOLOGY: Nine hundred extracted mandibular premolars were examined. After the length of the teeth was measured, the presence of developmental grooves and furcated roots was noted. Following the preparation of access cavities, pulp tissue was removed and the canal systems were stained. The teeth were then rendered clear by demineralization and immersion in methyl salicylate. Cleared teeth were examined and the following features were evaluated: (i) type of root canals; (ii) presence and location of lateral canals; transverse anastomosis; (iii) location of apical foramina; and (iv) frequency of apical deltas. RESULTS: The mean lengths of first and second mandibular premolars were 22.6 mm (18-27.5 mm) and 22.2 mm (16-26.5 mm), respectively. Although the majority of the specimens corresponded to Vertucci's classification scheme, analysis of this large data set revealed four additional root canal morphologies. Variable root canal morphologies were found in the mandibular first premolars; two separate apical foramina were found in 33% of the teeth with two canals, compared to 6.2% with one apical foramen. Teeth with three separate apical foramina were scarce (2.2%). The majority of the mandibular second premolars had a single canal; 72% of teeth possessed type I canal systems, whilst 22.8% of the roots had two canals with two separate apical foramina. CONCLUSIONS: The prevalence of multiple canals in the investigated Jordanian mandibular premolars was high, especially for the second mandibular premolar, in comparison with previous studies performed on populations of different racial origin.     

The microscopic diagnosis and treatment of a mandibular second premolar with four canals

AIM: The purpose of this article is to report the case of a mandibular second premolar with four distinct canals. SUMMARY: It is generally recognized that incomplete instrumentation and cleaning of root canals will lead to failure in root-treated teeth. Before root canal treatment is performed, the clinician should be aware of the configuration of the pulp space of the tooth that is to be treated. Frequently, root canals are left untreated because the clinician fails to identify their presence, particularly in teeth that have anatomical variations or additional root canals. Traditionally, additional canals have been detected by clinical examination of the floor of the pulp chamber, and sometimes found radiographically. More recently microscopic examination of the pulp chamber using endodontic microscopy has assisted the identification of extra canals. A case report is presented that deals with the successful treatment of a mandibular second premolar with four canals. KEY LEARNING POINTS: Even in teeth with a low frequency of abnormal root canal anatomy, the possibility of additional root canals has to be considered in the clinical and radiographic examination of the patient. The ability to recognize and locate unsuspected canals is enhanced by microscopic investigation of the pulp chamber.     

Aetiology,incidence and morphology of the C‐shaped root canal system and its impact on clinical endodontics

The C‐shaped root canal constitutes an unusual root morphology that can be found primarily in mandibular second permanent molars. Due to the complexity of their structure, C‐shaped root canal systems may complicate endodontic interventions. A thorough understanding of root canal morphology is therefore imperative for proper diagnosis and successful treatment. This review aims to summarize current knowledge regarding C‐shaped roots and root canals, from basic morphology to advanced endodontic procedures. To this end, a systematic search was conducted using the MEDLINE, BIOSIS, Cochrane Library, EMBASE, Google Scholar, Web of Science, PLoS and BioMed Central databases, and many rarely cited articles were included. Furthermore, four interactive 3D models of extracted teeth are introduced that will allow for a better understanding of the complex C‐shaped root canal morphology. In addition, the present publication includes an embedded best‐practice video showing an exemplary root canal procedure on a tooth with a pronounced C‐shaped root canal. The survey of this unusual structure concludes with a number of suggestions concerning future research efforts.     

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.     

A cone-beam computed tomography study of root canal morphology of maxillary and mandibular premolars in a Turkish population

Aim. The aim of this study was to evaluate the root canal number and configuration of maxillary and mandibular premolar teeth by gender, intervals for decades, tooth position and unilateral or bilateral occurrence in a Turkish population using Cone Beam Computed Tomography(CBCT) scanning. Methodology. CBCT images of 5496 maxillary and mandibular premolars from 849 patients were evaluated. The following was evaluated in all the images: numbers of roots and root canals, the morphology of the root canal configuration according to the Vertucci classification, male–female differences in the tooth position and male–female differences in unilateral or bilateral occurrence. The reliability data were analyzed with a chi-square test. Results. The most prevalent root canal frequency was the two canals (86.2%) and type IV (76.9%) configuration for maxillary first premolar, one canal (59.7%) and type I (54.5%) canal configuration for second premolar. The incidence of one canal was higher in females and the occurrence of two or three canals was more common in males. The incidence of one canal was higher on the left side of maxillary premolars and the incidence of two canals was higher on the right side. Most mandibular first (93.5%) and second (98.5%) premolars had one canal. In general, females had one root canal of the mandibular premolar, whereas males had two or three canals. The type I configuration was most common and the incidence was higher on the right side. There were some differences found in the frequency distribution of the number of root canals and configuration of maxillary and mandibular premolar teeth according to intervals for decades. Conclusion. CBCT scanning provides comprehensive information about the root canal morphology of maxillary and mandibular premolar teeth. These data may help clinicians in root canal treatment of premolar teeth.     

3个根管的下颌第一前磨牙的根管治疗1例

3个根管的下颌第一前磨牙极其罕见,本文报道1例3个根管的下颌第一前磨牙的根管治疗,并着重探讨了根管探查和预备的要点。     

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。     

Root canal anatomy of mandibular first premolars in a southern Chinese population

Abstract Racial differences in dental crown morphology have long been recognized, but the frequency of genetically determined variations in the root canal anatomy of teeth has not been fully established. There is, therefore, a need to study the morphology of non-Caucasoid teeth to establish the existence and prevalence of racially determined root canal variations. In this study 100 mandibular first premolars of Chinese origin were accurately identified and radiographed in vitro to establish the frequency of root canal bifurcation. Thirty-six per cent of the sample presented with more than one canal. The division of these canals occurred at various levels of the root, and in all but one of the teeth the canals remained separate.     

Mandibular first premolar with two roots and three canals

This case report presents a relatively uncommon clinical case of a mandibular premolar with two roots and three canals. The possibility of additional root canals should be considered even in teeth with a low frequency of abnormal root canal anatomy. Sound knowledge of root canal anatomy, appropriate assessment of the pulp chamber floor, critical interpretation of radiographs and high-magnification examinations are highly desirable to achieve the best possible outcome in complicated root canal therapy.     

Root canal treatment of a mandibular first molar with three mesial root canals

The dynamic concept of the root canal system, describing a variable morphology of multiple root canals interconnected by anastomoses, has been established as the prevailing state in mandibular molars. This case report presents the treatment of a mandibular first molar with five root canals, of which three were located in the mesial root. A third middle root canal was found between the mesiobuccal and mesiolingual root canals. The morphological pattern of separate apical terminations of the three mesial root canals, as manifested in this case, is a very rare one and seldom encountered.     

双侧下颌第一恒磨牙融合根伴C形根管1例

下颌第一恒磨牙的牙根通常为2~3根伴2~4个根管,融合根伴C形根管较罕见。本文报道1例双侧均为融合根伴C型根管的下颌第一恒磨牙患者。     

Finding appropriate nickel-titanium instruments for lingual canals in mandibular first premolars with two canals: A micro-CT study

This study aimed to find appropriate nickel-titanium instruments for lingual canals in mandibular first premolars with two canals. Forty-two extracted mandibular first premolars with lingual canals (Vertucci type V) verified by micro-CT scanning were selected. The teeth were randomly divided into three groups, and their lingual canals were instrumented by M3, HyFlex CM and XP-endo Shaper, respectively. After instrumentation, the canal morphology was scanned again by micro-CT. The canal morphologies of pre- and post-instrumentation were reconstructed and aligned. Morphological changes of the lingual canals were evaluated. No instrument breakages occurred during the procedure of root canal instrumentation. HyFlex CM and XP-endo Shaper performed better than M3 files in preparation of lingual canals (Vertucci type V) of mandibular first premolars in terms of apical transportation and unprepared surface area.     

Evaluation of root canal morphology of maxillary premolars: a cone‐beam computed tomography study

The aim of this study was to evaluate the root canal configuration of maxillary premolars using cone‐beam computed tomography (CBCT). CBCT images of 999 maxillary premolars from a database were analysed to determine the frequency of the number of roots, root canals and Vertucci's classification. The associations among these variables were evaluated by Chi‐square test (P < 0.05). In the first premolars, 42.2% of single‐rooted teeth had a type II configuration, whereas 98.7% of 2‐rooted teeth showed type IV. In the second premolars, type I was the most prevalent (49.9%). The presence of two roots was more prevalent in first premolars, and the presence of one root was more prevalent in second premolars (P < 0.05). Male patients had a higher percentage of two roots compared with female patients (P < 0.05). Type IV and I was more prevalent in first and second premolars respectively (P < 0.05). There was a high frequency of 2‐rooted and single‐rooted teeth among maxillary first and second premolars respectively.     

Root and canal morphology of mandibular first and second molar teeth in a Jordanian population

Aim  To examine the root and canal morphology of mandibular permanent first and second molar teeth in a Jordanian population.
Methodology  A total of 685 extracted mandibular first and second permanent molar teeth were collected from dental clinics within north Jordan. The teeth were examined visually and the root number and morphology were recorded. After that, access cavities were prepared, pulp tissue dissolved by sodium hypochlorite and the root canals injected with Indian ink. Stained teeth were decalcified with 10% nitric acid, dehydrated with ascending concentrations of alcohol and rendered clear by immersion in methyl salicylate. The following observations were evaluated: (i) number of canals per root; (ii) number of root canals per tooth; (iii) canal configuration in each root; (iv) number and location of lateral canals and (v) presence of intercanal communications.
Results  Of 330 mandibular first molars, the majority had three (48%) or four (46%) canals, whilst 4% had a third disto-lingual root. Of 355 mandibular second molars, 58% had three canals, 19% two and 17% had four canals, whilst 10% had C-shaped roots. The most prevalent canal configuration in the mesial root of both first (53%) and second (40%) molars was type IV, and in distal roots was type I (54% in first and 79% in second molars).
Conclusions  Jordanian mandibular first and second molar teeth exhibit features close to the average Caucasian root and canal morphology.