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| Year : 2021 | Volume
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| Issue : 1 | Page : 104-109 |
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| An In-Vivo cone-beam computed tomography analysis of root and canal morphology of maxillary first permanent molars in an Indian population |
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Ajinkya Pawar1, Bhagyashree Thakur2, Ricardo Machado3, Sang W Kwak4, Hyeon-Cheol Kim4
1 Department of Conservative Dentistry and Endodontics, Nair Hospital Dental College, Mumbai, Maharashtra, India
2 Department of Dentistry, Civil Hospital, Thane, Maharashtra, India
3 Department of Endodontics, School of Dentistry, Regional University of Blumenau, Blumenau, Santa Catarina, Brazil
4 Department of Conservative Dentistry, School of Dentistry, Dental Research Institute, Pusan National University, Yangsan, South Korea
Click here for correspondence address and email
| Date of Submission | 08-Oct-2019 |
| Date of Decision | 13-Mar-2020 |
| Date of Acceptance | 05-Jul-2020 |
| Date of Web Publication | 13-Jul-2021 |
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 Abstract | | |
Background: The root and canal morphology of maxillary first permanent molars (MFPMs) is a very widely studied issue in endodontics. However, only one study has been conducted to date on this issue using cone-beam computed tomography (CBCT) in India, and the sample consisted of extracted teeth. Aim: To investigate the root and canal morphology of MFPMs in an Indian population, by using CBCT. Methods and Material: 487 bilateral MFPMs (974 teeth) were assessed and the root and canal morphology were determined according to Vertucci's classification. In addition, the prevalence of a second mesiobuccal canal in the mesiobuccal root (MB2) was correlated with gender, age and arch side. Results: Three roots were most commonly found in the MFPMs regardless of gender (P > 0.05), but this prevalence varied according to the side of the dental arch (P < 0.05). MB2 was present in 77.5% of 3-rooted teeth. Patients above 60 years had a higher incidence of these canals (84.7%) (P < .05). The occurrence of bilateral MB2 was 71.8% in 3-rooted MFPMs. Gender had no significant impact on the occurrence of bilateral MB2 in 3-rooted MFPMs (P > .05). The most common canal configuration was type IV (46.5%) and I (98.9%) in the mesiobuccal and distobuccal roots, respectively (P < .05). The prevalence of MB2 in 3-rooted MFPMs was higher in patients above 60 years of age. Conclusions: The root and canal morphology of MFPMs in an Indian population may have significant variations depending on the dental arch side and patient age.
Keywords: Cone-beam computed tomography, maxillary first permanent molars, root canal morphology
How to cite this article:
Pawar A, Thakur B, Machado R, Kwak SW, Kim HC. An In-Vivo cone-beam computed tomography analysis of root and canal morphology of maxillary first permanent molars in an Indian population. Indian J Dent Res 2021;32:104-9 |
How to cite this URL:
Pawar A, Thakur B, Machado R, Kwak SW, Kim HC. An In-Vivo cone-beam computed tomography analysis of root and canal morphology of maxillary first permanent molars in an Indian population. Indian J Dent Res [serial online] 2021 [cited 2023 Jun 4];32:104-9. Available from: https://www.ijdr.in/text.asp?2021/32/1/104/321385 |
| Introduction | |  |
The main goal of endodontic treatment is to maintain or recover the health of periapical tissues by cleaning and filling the root canal system.[1] Invariably, the clinician must know the root and canal morphology, as well as, its variations to achieve this objective. Missed canals are one of the major causes of endodontic failure.[2]
Throughout history, several techniques have been used to study root and canal morphology, such as radiographs,[3] micro/macroscopic sections,[3] staining and tooth clearing techniques,[4] and polyester resin impressions.[5] These approaches have been very important in driving the evolution of endodontics; however, currently, other techniques that allow the visualisation of teeth in three dimensions have been used more frequently.
Micro-computed tomography (micro-CT) is an emerging technology with several promising applications in many different fields of dentistry. In endodontics, micro-CT has been used for studying: I) root and canal morphology,[5] II) the extent of cleaning achieved after different instrumentation[6] and irrigation[7] protocols, respectively; III) the effectiveness of different techniques for removal of gutta-percha (retreatments)[8] and; IV) the quality of fillings made by different techniques.[9] However, micro-CT cannot be applied clinically.
Cone-beam computed tomography (CBCT) is the most accurate imaging exam for studying root and canal morphology and for treatment planning right before performing the endodontic treatment, that is, it has direct clinical application.[10] For this reason, several studies have been performed using this tool.[11],[12],[13] Some of this research has shown that this morphology has a racial predisposition.[11],[12] Considering that the Indian population is a mixture of several ethnic groups (Caucasian, Mongoloid and Negroid races),[14] it is important to study the root and canal morphology of this population's teeth.
In the only study that has been conducted to date on this issue using cone-beam computed tomography (CBCT) in India, the sample consisted of just 220 extracted teeth.[15] Therefore, the aim of the present study was to make an in vivo evaluation of the root and canal morphology of a greater number of teeth in an Indian population, by means of CBCT.
| Material and Methods | | |
Subjects
CBCT images from 1227 patients were identified in the database of an Oral Radiology department in India. The patients were referred to this department between August 2014 and April 2015 and required tomographic examination using CBCT imaging as part of their dental examination, diagnosis and treatment planning. Written and verbal consent from each patient was obtained and approved by the university's institutional review board.
Inclusion and exclusion criteria
The following cases were included in the study[16]:
- Bilateral MFPMs.
- Fully matured and erupted MFPMs.
- Molars without root canal fillings, posts, crown restorations, apical periodontitis, or any other odontogenic or non-odontogenic pathology.
The following cases were excluded[13]:
- Teeth with open apices, root resorption or calcification.
CT scans
CBCT images were acquired with a ProMax 3D Mid (Planmeca OY, Helsinki, Finland). The scans were obtained according to the following parameters: 90 kV and 8 mA, with various fields of view (FOV), ranging from 16 x 16 cm for the larger scans to 5 x 4 cm for a limited FOV. The Isotropic resolution was set at 0.1 mm, with 8.9 to 26.9 sec scanning time. The slice thickness ranged between 0.1 and 0.4 mm. All CBCT exposures were performed with the minimum exposure needed to achieve adequate image quality and by an experienced licensed radiologist. The ALARA (as low as reasonably achievable) protocol was followed strictly, exposing patients to the least amount of radiation, but still gaining the most useful information for proper diagnosis.[13]
Serial sagittal, coronal and axial views of CBCT images were examined carefully by 2 endodontists independently until an agreed diagnosis was reached for each case. The digital imaging and communications in medicine (DICOM) images were examined, and the root and canal morphology were tabulated for each MFPM, according to the Vertucci classification.[4] Data on gender and age were also collected. The prevalence of a second mesiobuccal (MB2) canal in the mesiobuccal root was correlated with gender, age and arch side. Twenty randomly chosen cases (40 teeth) were examined and diagnosed a second time by the same 2 endodontists 2 weeks apart; the intra-rater reliability was calculated by using the Cohen kappa. Agreement was noted as excellent if k ≥ 0.75, good if 0.60 ≤ k < 0.75, intermediate if 0.4 ≤ k < 0.60 and poor if k < 0.4.[17]
Statistics
The prevalence of 3-rooted MFPMs was calculated, as well as the descriptive statistics (age, ethnicity and gender). The Pearson χ2 test was used to analyse the differences in the prevalence of 3-rooted maxillary first molars between the left and right sides and by gender. Differences in MB2 prevalence by age were also analysed with the χ2 test. SAS software 9.3 (SAS Institute Inc, Cary, NC) was used in this study, with a significance set at α = 0.05.[16]
| Results | | |
The intra-rater reliability was 0.81 (excellent). A total of 1227 CBCT scans were examined for inclusion criteria. Of these, 487 bilateral MFPMs (974 teeth) met all the criteria and were included in the study. The mean age of the patients evaluated was 38-years-old. Of the total scans, 239 were of female patients (ages ranging from 16 to 61 years; the average age of 36 years), and 248 were of male patients (age ranges from 14 to 68 years; the average age of 40 years). Of the 974 teeth, 966 (99.1%) exhibited 3 roots, only 8 (0.9%) exhibited 2 roots [Figure 1], and there was no single-rooted tooth. There was no statistically significant difference in the prevalence of 3-rooted MFPMs between males (476 teeth, 49.2%) and females (490 teeth, 50.8%). The prevalence of 3-rooted MFPMs varied according to the side of the dental arch. All the teeth from the right side (100%) and 98.3% of those from the left side were 3-rooted (P < 0.05). | Figure 1: Case of maxillary first permanent molars with 2 roots bilaterally
Click here to view |
MB2 canals were present in 749 of the 966 (77.5%) 3-rooted teeth. Age had a significant impact on the occurrence of MB2 canals. Patients over 60 years showed a significantly higher incidence of MB2 canals (89 of the 105 teeth, 84.7%), compared with patients in the 30-39 year age group (166 of 231 teeth, 71.2%) (P < 0.05) [Table 1]. The occurrence of bilateral MB2 canals was 71.8% in 3-rooted MFPMs [Figure 2]. Gender had no significant impact on the occurrence of bilateral MB2 canals in 3-rooted MFPMs (P > 0.05). | Table 1: Prevalence of second mesiobuccal canal (MB2), considering patient age
Click here to view |
 | Figure 2: Case of bilateral incidence of maxillary first permanent molars with second mesiobuccal canals
Click here to view |
The canal configuration demonstrated variation only in 3-rooted teeth. In the mesiobuccal roots, the most common canal configuration was type IV (46.5%), followed by type I (27.3%), type II (23.2%), type V (1.9%) and type III (1.1%) (P < 0.05). In the distobuccal roots, the most common canal configuration was type I (98.9%), followed by type II (0.6%) and type V (0.5%) (P < 0.05). The palatal root exhibited type I configuration in all the teeth studied (100%). There was no significant gender difference in the percentage distribution of canal configuration in any of the roots (P > 0.05). The canal configuration for 2-rooted MFPMs was the type I in all the buccal and palatal roots (100%) [Table 2]. | Table 2: Prevalence of canal configuration according to Vertucci's classification, considering patient gender
Click here to view |
| Discussion | | |
MFPMs erupt early, perform a major masticatory function, and have a high rate of dental caries; hence, they require frequent endodontic treatment.[18] Dentists have been devoting time to studying these teeth due to their substantial root and canal morphology variations, as pointed out by several previous studies carried out around the world.[15],[19],[20] These studies have shown that there is an ethnic factor associated with the root and canal morphological variations in these teeth. Considering that the Indian population is a mixture of several ethnic groups (Caucasian, Mongoloid and Negroid races)[14] and that only one in vitro study has been conducted to date on the root and canal morphology of MFPMs using CBCT in India,[15] the aim of this study was to perform the same analysis in vivo.
CBCT is a non-invasive radiographic imaging method in which the images acquired can be visualised in three dimensions. The images acquired by CBCT have been reported to be useful in making pre-intervention diagnosis and treatment planning in endodontics. Blatner et al. compared CBCT imaging with clinical sectioning for the purpose of identifying MB2 canals and found that CBCT was just as reliable.[21] Domark et al. conducted a cadaver model study in which they evaluated the accuracy of CBCT and micro-CT in detecting the number of root canals in the mesiobuccal roots of maxillary molars. The authors found no statistically significant differences between either research methods.[22] Micro-CT enables the evaluation of several features, including root and canal morphology,[5] the extent of cleaning achieved after different instrumentation[6] and irrigation[7] protocols, respectively; the effectiveness of different techniques for removal of gutta-percha (retreatments),[8] and the quality of fillings made by different techniques.[9] These features can be evaluated much more reliably by micro-CT compared to CBCT. However, micro-CT can be used only as an important research methodology to acquire information from extracted teeth and has no direct clinical applicability. On the other hand, CBCT has frequently been used for the study of the root and root canal morphology of different teeth in vivo,[23],[24] and as an important aid in resolving complex cases.[10]
In the present study, 966 of the 974 teeth (99.1%) exhibited 3 roots, only 8 teeth (0.9%) exhibited 2 roots, and there was no single-rooted tooth. These results are in accordance with previous reports on the root and canal morphology of maxillary molars, from India.[15],[25] A high incidence of 3-rooted MFPMs has also been reported in other populations throughout the world.[16],[18],[26],[27] There was no statistically significant difference in the prevalence of 3-rooted MFPMs in regard to gender. As mentioned earlier, 3-rooted MFPMs represent the most common morphological configuration in the same segment of the population, as reported in studies performed around the world.[13],[16],[26],[28],[29] Some of these studies did not analyse the incidence of this morphological feature specifically according to gender, but all of them had men and women composing the sample, and the same result was found.[13],[28],[29] Taken in itself, this means that there is a tendency for gender not to influence the prevalence of 3-rooted MFPMs in patients from the same population. However, when the prevalence of 3-rooted MFPMs is specifically investigated in regard to gender, and a balanced sample is used, this variable yields a more reliable analysis. In the study by Guo et al., 628 teeth of male and 628 teeth of female patients were analysed, and there was no statistically significant gender-based difference in the prevalence of 3-rooted MFPMs.[16] In our study, 248 teeth of male and 239 teeth of female patients were analysed, and we found the same result. Therefore, the findings of Guo et al.,[16] and our results once again point to the lack of scientific evidence that gender is capable of influencing the prevalence of 3-rooted MFPMs in patients from the same population.
On the other hand, the prevalence of 3-rooted MFPMs varied according to the side of the dental arch. All (100%) the teeth from the right side and 98.3% of those from the left side were 3-rooted. In the study by Guo et al., the prevalence of 3-rooted maxillary first molars was also greater on the right side (317 out of 317, 100%), compared with the left side (311 out of 317, 98.1%) (P = 0.03); however, the authors did not discuss this result in their paper.[16] To the best of our knowledge, there is no scientific evidence to explain this result. Therefore, we believe that we are facing a type I statistical error. Type I statistical errors occur when results with statistical significance are reached by chance.[17]
In the current study, MB2 canals occurred in 3-rooted MFPMs, totalling 77.5% (749 out of 966 teeth), a result higher than that of a Korean[30] and a North American population.[16] Khademi et al. showed that the prevalence of the MB2 canal was 70.2% in maxillary first molars of an Iranian population.[26] Rouhani et al. evaluated the root and canal morphology of 125 first and 125-second maxillary molars of an Iranian population and reported that three roots were found in 97% and 89% of first and second maxillary molars, respectively, and that 53% of first and 20% of second maxillary molars had an MB2 canal. Most of the teeth were 3-rooted, as in the present study. However, the prevalence of the MB2 canal was about 20% lower than that of the present study.[31] Differences related to the number of roots and canals may be attributed to different ethnic subgroups and sample sizes, and/or differences in the design of the evaluations.[26] Moreover, our results showed that the incidence of MB2 canals was related to age. Patients over 60 years showed a higher prevalence of MB2 canals, corroborating the results of Guo et al.[16] However, contrasting results have also been reported, in which the MB2 canal was found to have a high prevalence in patients within the 20–30-year age group in a Chinese population.[27] As mentioned before, differences related to the number of roots and canals may be attributed to different ethnic subgroups and sample sizes, and/or differences in the design of the evaluations.[26] Therefore, it is important to note that, in our study, only 105 teeth with three roots were found in the group of patients older than 60 years. In comparison, 231 and 186 patients were in the group of patients between 30 and 40 years and between 50 and 60 years of age, respectively [Table 1]. The difference in the number of patients evaluated by age group may have led to patients older than 60 years having teeth with a higher incidence of MB2 canals.
Our results showed that the occurrence of bilateral MB2 canals in 3-rooted MFPMs was 71.8%. This is in agreement with previous studies.[30],[32] Kim et al. observed that both the first and second molars presented a high tendency for the bilateral occurrence of an MB2 canal; however, the concurrence rate of MB2 in the 2 adjacent molars was lower than that of MB2 in the bilateral molars. Bilateral symmetry in the presence or absence of MB2 was found in 88.10% of the MFPMs and 82.07% of the second molars. The adjacent concurrence was 64.40%. This finding indicates to clinicians that an MB2 canal in a molar probably occurs in an adjacent molar, especially a contralateral molar. Gender had no significant impact on the occurrence of bilateral MB2 canals in 3-rooted MFPMs,[30] which is consistent with other previous studies.[16],[30]
The canal configurations demonstrated variation only in 3-rooted teeth. In the mesiobuccal roots, the most common canal configuration was type IV (46.5%), followed by type I (27.3%), type II (23.2%), type V (1.9%), and type III (1.1%). Several studies also concluded that the most common mesiobuccal canal configuration in the first molar mesiobuccal roots was type IV.[16],[29],[30] However, Ratanajirasut et al. and Khademi et al. observed that the most common configurations in the mesiobuccal roots of MFPMs were type I and II.[32],[28] Considering that all these studies used CBCT scans, the difference in results may be attributed to the sample sizes and/or ethnical factors.
The distobuccal roots of the 3-rooted MFPMs evaluated were associated with very few anatomical variations; in that type I (955 of 966 teeth, 98.9%) was the most common, followed by type II (6 out of 966 teeth, 0.6%), and type V (6 out of 966 teeth, 0.6%). These results were slightly lower compared with the study performed by Neelakantan et al. and higher compared with the report by Singh and Pawar.[15],[25] Comparatively, Neelakantan et al. evaluated 220 maxillary first and 205 second permanent molars also using CBCT scans, but the scanner and the technical parameters used were different from those used in our study.[15] Singh and Pawar, evaluated 300 permanent maxillary molars (first, second and third maxillary molars – 100 each) by dye penetration, decalcification and clearing procedures.[25] Considering that both studies were conducted in India,[15],[25] the difference in results may be due to the different sample sizes and/or methodological designs of the studies.[26]
Only 8 of the 974 teeth (0.9%) exhibited 2 roots. Both roots were also classified as type I. Two-rooted MFPMs were found to be rare in the population studied.[15],[25] The root canal configurations of the palatal roots of all the teeth were also classified as type I. This finding is in line with Alavi et al.,[33] Rwenyonyi et al.[34] and Faramarzi et al.[35] Moreover, other studies[15],[31],[36],[37] show the same results, but with different prevalence rates (from 88.1 to 96.6%). However, unusual root canal morphology in the palatal root has already been found.[38]
CBCT offers a non-invasive approach to identifying anatomical variations of root canals, insofar as it allows the debridement of the entire root canal system, thus making endodontic practice more predictable. Several studies have reported on the quality of CBCT imaging and its clinical application in studying root and canal morphology before undertaking clinical endodontic treatment.[11],[12],[15],[16],[19],[20],[23] Nevertheless, CBCT imaging should be indicated only in cases in which complex anatomy and/or morphology is suspected. It is worth remembering that CBCT imaging still uses ionizing radiation. Although radiation is minimal, we should always bear in mind the ALARA protocol, and the evidence-based on the data collected. Endodontic cases should be assessed individually, and patients should always be exposed to the least amount of radiation needed to gain the most useful information for proper diagnosis. In the cases in which unexpected complex anatomy is visualized after access, or when canals are not found, intraoperative CBCT imaging is always an excellent possibility.[13]
| Conclusions | | |
The root canal anatomy of MFPMs in an Indian population may have significant variations, considering the side of the dental arch and the age of the patients. All the teeth from the right side were 3-rooted. The prevalence of MB2 canals in 3-rooted MFPMs was significantly high in patients above 60 years of age. The most common canal configuration in the mesiobuccal roots was type IV.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patients have given consent for their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Nil.
Conflicts of interest
The authors deny any conflicts of interest related to this study.
| References | | |
| 1. | Popic V. Basic principles in endodontic therapy. Acta Stomatol Croat 1968;3:222-7.  |
| 2. | Costa FFNP, Pacheco-Yanes J, Siqueira JF Jr, Oliveira ACS, Gazzaneo I, Amorim CA, et al. Association between missed canals and apical periodontitis. Int Endod J 2019;52:400-6. |
| 3. | Degerness RA, Bowles WR. Dimension, anatomy and morphology of the mesiobuccal root canal system in maxillary molars. J Endod 2010;36:985-9. |
| 4. | Vertucci FJ. Root canal anatomy of the human permanent teeth. Oral Surg Oral Med Oral Pathol 1984;58:589-99. |
| 5. | Wolf TG, Paque F, Zeller M, Willershausen B, Briseno-Marroquin B. Root canal morphology and configuration of 118 mandibular first molars by means of micro-computed tomography: An ex vivo study. J Endod 2016;42:610-4. |
| 6. | Zuolo ML, Zaia AA, Belladonna FG, Silva EJNL, Souza EM, Versiani MA, et al. Micro-CT assessment of the shaping ability of four root canal instrumentation systems in oval-shaped canals. Int Endod J 2018;51:564-71. |
| 7. | Silva EJNL, Carvalho CR, Belladonna FG, Prado MC, Lopes RT, De-Deus G, et al. Micro-CT evaluation of different final irrigation protocols on the removal of hard-tissue debris from isthmus-containing mesial root of mandibular molars. Clin Oral Investig 2019;23:681-7. |
| 8. | Kaloustian MK, Nehme W, El Hachem C, Zogheib C, Ghosn N, Michetti J, et al. Evaluation of two shaping systems and two ultrasonic irrigation devices in removing root canal filling material from mesial roots of mandibular molars: A micro CT study. Dent J (Basel) 2019;7:1-9. |
| 9. | Castagnola R, Marigo L, Pecci R, Bedini R, Cordaro M, Liborio Coppola E, et al. Micro-CT evaluation of two different root canal filling techniques. Eur Rev Med Pharmacol Sci 2018;22:4778-83. |
| 10. | Almeida G, Machado R, Sanches Cunha R, Vansan LP, Neelakantan P. Maxillary first molar with 8 root canals detected by CBCT scanning: A case report. Gen Dent 2015;63:68-70. |
| 11. | Martins JNR, Gu Y, Marques D, Francisco H, Carames J. Differences on the root and root canal morphologies between Asian and White Ethnic Groups analyzed by cone-beam computed tomography. J Endod 2018;44:1096-104. |
| 12. | Shemesh A, Kavalerchik E, Levin A, Ben Itzhak J, Levinson O, Lvovsky A, et al. Root canal morphology evaluation of central and lateral mandibular incisors using cone-beam computed tomography in an Israeli population. J Endod 2018;44:51-5. |
| 13. | Silva EJ, Nejaim Y, Silva AI, Haiter-Neto F, Zaia AA, Cohenca N, et al. Evaluation of root canal configuration of maxillary molars in a Brazilian population using cone-beam computed tomographic imaging: An in vivo study. J Endod 2014;40:173-6. |
| 14. | Reich D, Thangaraj K, Patterson N, Price AL, Singh L. Reconstructing Indian population history. Nature 2009;461:489-94. |
| 15. | Neelakantan P, Subbarao C, Ahuja R, Subbarao CV, Gutmann JL. Cone-beam computed tomography study of root and canal morphology of maxillary first and second molars in an Indian population. J Endod 2010;36:1622-7. |
| 16. | Guo J, Vahidnia A, Sedghizadeh P, Enciso R. Evaluation of root and canal morphology of maxillary permanent first molars in a North American population by cone-beam computed tomography. J Endod 2014;40:635-9. |
| 17. | Daniel WW, Cross CL. Biostatistics: A Foundation for Analysis in the Health Sciences. 11 th ed.. Hoboken, NJ: Wiley; 2019. p. 1 online resource. |
| 18. | Zhang Y, Xu H, Wang D, Gu Y, Wang J, Tu S, et al. Assessment of the second mesiobuccal root canal in maxillary first molars: A cone-beam computed tomographic study. J Endod 2017;43:1990-6. |
| 19. | Gomes Alves CR, Martins Marques M, Stella Moreira M, Harumi Miyagi de Cara SP, Silveira Bueno CE, Lascala CA, et al. Second mesiobuccal root canal of maxillary first molars in a Brazilian population in high-resolution cone-beam computed tomography. Iran Endod J 2018;13:71-7. |
| 20. | Rezaeian M, Rouhani Tonekaboni M, Iranmanesh F. Evaluating the root canal morphology of permanent maxillary first molars in Iranian population. Iran Endod J 2018;13:78-82. |
| 21. | Blattner TC, George N, Lee CC, Kumar V, Yelton CD. Efficacy of cone-beam computed tomography as a modality to accurately identify the presence of second mesiobuccal canals in maxillary first and second molars: A pilot study. J Endod 2010;36:867-70. |
| 22. | Domark JD, Hatton JF, Benison RP, Hildebolt CF. An ex vivo comparison of digital radiography and cone-beam and micro computed tomography in the detection of the number of canals in the mesiobuccal roots of maxillary molars. J Endod 2013;39:901-5. |
| 23. | de Lima CO, de Souza LC, Devito KL, do Prado M, Campos CN. Evaluation of root canal morphology of maxillary premolars: A cone-beam computed tomography study. Aust Endod J 2019;45:196-201. |
| 24. | Fernandes NA, Herbst D, Postma TC, Bunn BK. The prevalence of second canals in the mesiobuccal root of maxillary molars: A cone beam computed tomography study. Aust Endod J 2019;45:46-50. |
| 25. | Singh S, Pawar M. Root canal morphology of South Asian Indian maxillary molar teeth. Eur J Dent 2015;9:133-44. [ PUBMED] [Full text] |
| 26. | Khademi A, Zamani Naser A, Bahreinian Z, Mehdizadeh M, Najarian M, Khazaei S, et al. Root morphology and canal configuration of first and second maxillary molars in a selected Iranian population: A cone-beam computed tomography evaluation. Iran Endod J 2017;12:288-92. |
| 27. | Zheng QH, Wang Y, Zhou XD, Wang Q, Zheng GN, Huang DM, et al. A cone-beam computed tomography study of maxillary first permanent molar root and canal morphology in a Chinese population. J Endod 2010;36:1480-4. |
| 28. | Plotino G, Tocci L, Grande NM, Testarelli L, Messineo D, Ciotti M, et al. Symmetry of root and root canal morphology of maxillary and mandibular molars in a white population: A cone-beam computed tomography study in vivo. J Endod 2013;39:1545-8. |
| 29. | Zhang R, Yang H, Yu X, Wang H, Hu T, Dummer PM, et al. Use of CBCT to identify the morphology of maxillary permanent molar teeth in a Chinese subpopulation. Int Endod J 2011;44:162-9. |
| 30. | Kim Y, Lee SJ, Woo J. Morphology of maxillary first and second molars analyzed by cone-beam computed tomography in a korean population: Variations in the number of roots and canals and the incidence of fusion. J Endod 2012;38:1063-8. |
| 31. | Rouhani A, Bagherpour A, Akbari M, Azizi M, Nejat A, Naghavi N, et al. Cone-beam computed tomography evaluation of maxillary first and second molars in Iranian population: A morphological study. Iran Endod J 2014;9:190-4. |
| 32. | Ratanajirasut R, Panichuttra A, Panmekiate S. A Cone-beam computed tomographic study of root and canal morphology of maxillary first and second permanent molars in a Thai population. J Endod 2018;44:56-61. |
| 33. | Alavi AM, Opasanon A, Ng YL, Gulabivala K. Root and canal morphology of Thai maxillary molars. Int Endod J 2002;35:478-85. |
| 34. | Rwenyonyi CM, Kutesa AM, Muwazi LM, Buwembo W. Root and canal morphology of maxillary first and second permanent molar teeth in a Ugandan population. Int Endod J 2007;40:679-83. |
| 35. | Faramarzi F, Vossoghi M, Shams B, Vossoghi M, Khoshbin E. Cone beam computed tomography of maxillary first molar in an Iranian population. Avicenna J Dent Res 2015;7:1-5. |
| 36. | Sert S, Bayirli GS. Evaluation of the root canal configurations of the mandibular and maxillary permanent teeth by gender in the Turkish population. J Endod 2004;30:391-8. |
| 37. | Naseri M, Safi Y, Akbarzadeh Baghban A, Khayat A, Eftekhar L. Survey of anatomy and root canal morphology of maxillary first molars regarding age and gender in an Iranian population using cone-beam computed tomography. Iran Endod J 2016;11:298-303. |
| 38. | Ghotbi Rad SF, Havaei SR, Mousavi E, Kazemian R. Endodontic retreatment of a maxillary first molar with unusual palatal root canal morphology: A case report. J Dentomaxillofac Radiol Pathol Surg 2014;3:32-5. |
Correspondence Address:
Dr. Ajinkya Pawar
Department of Conservative Dentistry and Endodontics, Nair Hospital Dental College, Mumbai, Maharashtra
India
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/ijdr.IJDR_782_19
[Figure 1], [Figure 2]
[Table 1], [Table 2] |
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| This article has been cited by | | 1 |
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