The Prevalence of Second Distal Canals in the Mandibular First Molars: A Histological and Cone Beam Computed Tomography Study
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Abstract
Purpose: The prevalence of the Second Distal Canal (SDC) in the Mandibular First Molar (MFM) was assessed using histological and Cone Beam Computed Tomography (CBCT) studies.
Materials and Methods: This study included a total of 348 extracted MFM, which were divided into 6 groups according to gender and age. All the teeth were viewed by one CBCT device, and then the teeth were histologically examined. The images were evaluated, and the obtained results were analyzed by SPSS software using the Chi-square test. The comparison was considered statistically significant at p<0.05.
Results: The prevalence rate of the canals was 171 (49.13%), males and females were 89 and 82, respectively, and according to the level of sectioning, they were found to be 43.94% of all the sections, with the lowest 16.11% and 15.62% at level 5 (coronal level) and level 1 (apical level) when viewed only histologically, being 110, while when viewed histologically and by CBCT, there were 61 teeth for the SDC, respectively, which was more in younger than older patients with no statistically significant difference.
Conclusion: The prevalence rate of the SDC seen by CBCT was 17.32%, while histologically it was 49.13%, respectively. Clinically, many canals cannot be detected because of their small size, which cannot be seen radiographically.
1- J Reuben, N Velmurugun and D Kandaswamay, "The evaluation of root canal morphology of the mandibular first molar in an Indian population using spiral computed tomography scan: An in vitro study," J Endod, Vol. 34 (No. 2), pp. 212-215, (2008).
2- FB Teixeira, CL Sano, BP Gomes, AA Zaia, CC Ferraz and FJ Souza-Filho, "A preliminary in vitro study of the incidence and position of the root isthmus in maxillary and mandibular first molars," International Endodontic Journal, Vol. 36 (No. 4), pp. 276-280, (2003).
3- AQ Talib and HF Al-Huwaizi, "Assessment of the effect of different irrigation protocols on penetration of irrigation solution into simulated lateral canals," European Endodontic Journal, Vol. 9, (No. 2), pp. 146-153, (2024).
4- LA Abdulrazaq, AH Ali and F Foschi, "Minimally invasive access cavities in endodontics," Journal Baghdad College Dentistry, Vol. 35 (No. 2), pp. 65-75, (2023).
5- AH Ali, AF Mahdee, NH Fadhil and DM Shihab, "Prevalece of periapical lesion in non endodontically and endodontically treated teeth in urban Iraqi subpopulation," Journal of Clinical and Expermental Dentistry, Vol. 14 (No. 11), pp. 953-958, (2022).
6- M Hasheminia, H Razavian, L Khorrami, H Mosleh and S Mohamadi, "Prevalence of middle mesial canal in mandibular first molar using cone-beam computed tomography technique," Dental Research Journal, Vol. 18, pp. 42, (2021).
7- LF Navarro, A Luzi, AA Garcia and AH Garcia, "Third canal in the mesial root of permanent mandibular first molars: Review of the literature and presentation of 3 clinical reports and 2 in vitro studies," Medicina Oral Patologia Oral Y Cirugia Bucal, Vol. 12 (No. 8), pp. 605-609, (2007).
8- DM Shihab and AF Mahdee, "Root and root canal morphology, study methods and classification", Journal Baghdad College Dentistry, Vol. 33 (No. 4), pp. 11-19, (2021).
9- S Sert, V Aslanalp and J Tanalp, "Investigation of the root canal configuration of mandibular permanent teeth in the Turkish population," International Endodontic Journal, Vol. 37 (No. 7), pp. 494-499, (2004).
10- Y Yang, B Wu, J Zeng and M Chen, "Classification and morphology of middle mesial canals of mandibular first molars in a southern Chinese subpopulation: a cone-beam computed tomographic study," BMC Oral Health, Vol. 20 (No. 1), pp. 358, (2020).
11- R Alroomy, F Elbaz, A Asiri, B Almulhim, M Kumari and T Gunaranjan, "Assessment of middle mesial canals in mandibular first molar using CBCT. An in vivo study," European Review for Medical and Pharmacological Sciences, Vol. 26 (No. 8), pp. 2861-2866, (2022).
12- M Tahmasbi, P Jalali, MK Nair, S Barghan and UP Nair, "Prevalence of Middle Mesial Canals and Isthmi in the Mesial Root of Mandibular Molars: An In Vivo Cone-beam Computed Tomographic Study," J Endod, Vol. 43 (No. 7), pp. 1080-1083, (2017).
13- X Hu, Z Huang, Z Huang, L Lei, M Cui and X Zhang, "Prevalence of isthmi in mesial roots and associated factors. An in vivo analysis," Surgical and Radiologic Anatomy, Vol. 41 (No. 7), pp. 815-822, (2019).
14- E Inaty, C Jabre, G Haddad, W Nehme, I Khalil and A Naaman, "Anatomical Investigation of Middle Mesial Canals of Mandibular Molars in a Middle Eastern Population: A Cross-sectional Cone-beam Computed Tomography Study," Journal of Contemporary Dental Practice, Vol. 21 (No. 8), pp. 910-915, (2020).
15- AA Al-Maswary, HW Almadhoon, A Elkhateb, A Hamdallah and E Halboub, "The Global Prevalence of Middle Mesial Canal in Mandibular First and Second Molars Assessed by Cone Beam Computed Tomography: A Systematic Review and Meta-Analysis," J Endod, Vol. 49 (No. 6), pp. 638-656, (2023).
16- F Pertek Hatipoğlu, G Mağat, O Hatipoğlu, N Taha, S Alfirjani and IZ Abidin, "Assessment of the Prevalence of Middle Mesial Canal in Mandibular First Molar: A Multinational Cross-sectional Study with Meta-analysis," J Endod, Vol. 49 (No. 5), pp. 549-558, (2023).
17- UA Bhatti, M Muhammad, MQ Javed and M Sajid, "Frequency of middle mesial canal in mandibular first molars and its association with various anatomic variables," Australian Endodontic Journal, Vol. 48 (No. 3), pp. 494-500, (2022).
18- EM Weinberg, AE Pereda, S Khurana, PP Lotlikar, C Falcon and C Hirschberg, "Incidence of Middle Mesial Canals Based on Distance between Mesial Canal Orifices in Mandibular Molars: A Clinical and Cone-beam Computed Tomographic Analysis." J Endod, Vol. 46 (No. 1), pp. 40-43, (2020).
19- CM Rwenyonyi, A Kutesa, LM Muwazi and W Buwembo, "Root and canal morphology of mandibular first and second permanent molar teeth in a Ugandan population," Odontology, Vol. 97 (No. 2), pp. 92-96, (2009).
20- K Gulabivala, TH Aung, A Alavi and YL Ng, "Root and canal morphology of Burmese mandibular molars," International Endodontic Journal, Vol. 34 (No. 5), pp. 359-370, (2001).
21- M Karapinar-Kazandag, BR Basrani and S Friedman, "The operating microscope-enhances detection and negotiation of accessory mesial canals in mandibular molars," J Endod, Vol. 36 (No. 8), pp. 1289–1294, (2010).
22- D Baugh and J Wallace, "Middle mesial canal of the mandibular first molar: A case report and literature review," J Endod, Vol. 30 (No. 3), pp. 185-186, (2004).
23- TP Cotton, TM Geisler, DT Holden, SA Schwartz and WC Schindler, "Endodontic applications of cone-beam volumetric tomography," J Endod, Vol. 33 (No. 9), pp. 1121-1132, (2007).
24- SK Sharma, SK Mudgal, K Thakur and R Gaur, "How to calculate sample size for observational and experimental nursing research studies," National Journal of Physiology, Pharmacy and Pharmacology, Vol. 10 (No. 1), pp. 1-8, (2020).
25- AK Khangura, S Gupta, A Gulati and S Singh, "Tooth decalcification using different decalcifying agents - A comparative study," Journal of Oral and Maxillofacialpathology, Vol. 25 (No. 3), pp. 463-469, (2021).
26- FJ Vertucci and RG Williams, "Root canal anatomy of the mandibular first molar," Journal of the New Jersey Dental Association, Vol. 45 (No. 3), pp. 27-28 passim, (1974).
27- FP Hatipoğlu, G Mağat, O Hatipoğlu, H Al-Khatib, AS Elatrash, IZ Abidin, T Kulczyk, MAM Alkhawas, GD Buchanan, M Kopbayeva, SBDS Surendar, MD S, MQ Javed, AA Madfa, S Bürklein, S Mimica, UB Bhatti, TI Maratovna, PJ Palma, JF Brochado Martins, "Assessment of the Prevalence of Radix Entomolaris and Distolingual Canal in Mandibular First Molars in 15 Countries: A Multinational Cross-sectional Study with Meta-analysis," J Endod, Vol. 49 (No. 10), pp. 1308-1318, (2023).
28- JNR Martins, C Nole, HF Ounsi, P Parashos, G Plotino, MF Ragnarsson, RR Aguilar, F Santiago, HC Seedat, W Vargas, M von Zuben, Y Zhang, H Alfawaz, MAM Alkhawas, Z Altaki, L Berti, C Boveda, I Cassim, A Chaniotis, D Flynn, JA Gonzalez, J Kottoor, A Monroe, EJNL Silva and MA Versiani, "Worldwide Assessment of the Mandibular First Molar Second Distal Root and Root Canal: A Cross-sectional Study with Meta-analysis," J Endod, Vol. 48 (No. 2), pp. 223-233, (2022).
29- MF Reyhani, S Rahimi and S Shahi, "Root canal therapy of a mandibular first molar with five root canals: a case report," Iran Endod J Fall, Vol. 2 (No. 3), pp. 110-112, (2007).
30- S Poorni, R Kumar and R Indira, "Canal complexity of a mandibular first molar," J Conserv Dent, Vol. 12 (No. 1), pp. 37-40, (2009).
31- G Chen, H Yao and C Tong, "Investigation of the root canal configuration of mandibular first molars in a Taiwan Chinese population," International Endodontic Journal, Vol. 42 (No. 11), pp. 1044-9, (2009).
32- J Kottoor, R Sudha and N Velmurugan, "Middle distal canal of the mandibular first molar: a case report and literature review," International Endodontic Journal, Vol. 43 (No. 8), pp. 714-722, (2010).
33- F Alnassar, Y Aldahman, A Altuwalah, A Aldafaas, R A-Sadhan and W Alnassar, "Assessment of the prevalence and configuration of middle distal canals in the mandibular molars in a Saudi subpopulation using Cone-Beam computed tomography," The Saudi Dental Journal, Vol. 34 (No. 2), pp. 150-154, (2022).
34- S Jain, "Mandibular first molar with three distal canals," Journal of Conservative Dentistry, Vol. 14 (No. 4), pp. 438-439, (2011).
35- JYY Pan, A Parolia, SR Chuah, S Bhatia, S Mutalik and A Pau, "Root canal morphology of permanent teeth in a Malaysian subpopulation using cone-beam computed tomography," BMC Oral Health, Vol. 19 (No. 1), pp. 14, (2019).
36- ME Kolsuz, C Evli, U Aksoy, M Koohnavard, S Aksoy and K Orhan, "Influence of voxel size and filter type on detecting vertical root fracture using CBCT," Australian Endodontic Journal, Vol. 49, pp. 439-446, (2023).
37- OB Dogan, H Boyacioglun and D Goksulak, "Machine learning assessment of dental age classification based on CBCT images a different approach," Dento Maxillo Facial Radiology, Vol. 53 (No. 1), pp. 67-73, (2024).
2- FB Teixeira, CL Sano, BP Gomes, AA Zaia, CC Ferraz and FJ Souza-Filho, "A preliminary in vitro study of the incidence and position of the root isthmus in maxillary and mandibular first molars," International Endodontic Journal, Vol. 36 (No. 4), pp. 276-280, (2003).
3- AQ Talib and HF Al-Huwaizi, "Assessment of the effect of different irrigation protocols on penetration of irrigation solution into simulated lateral canals," European Endodontic Journal, Vol. 9, (No. 2), pp. 146-153, (2024).
4- LA Abdulrazaq, AH Ali and F Foschi, "Minimally invasive access cavities in endodontics," Journal Baghdad College Dentistry, Vol. 35 (No. 2), pp. 65-75, (2023).
5- AH Ali, AF Mahdee, NH Fadhil and DM Shihab, "Prevalece of periapical lesion in non endodontically and endodontically treated teeth in urban Iraqi subpopulation," Journal of Clinical and Expermental Dentistry, Vol. 14 (No. 11), pp. 953-958, (2022).
6- M Hasheminia, H Razavian, L Khorrami, H Mosleh and S Mohamadi, "Prevalence of middle mesial canal in mandibular first molar using cone-beam computed tomography technique," Dental Research Journal, Vol. 18, pp. 42, (2021).
7- LF Navarro, A Luzi, AA Garcia and AH Garcia, "Third canal in the mesial root of permanent mandibular first molars: Review of the literature and presentation of 3 clinical reports and 2 in vitro studies," Medicina Oral Patologia Oral Y Cirugia Bucal, Vol. 12 (No. 8), pp. 605-609, (2007).
8- DM Shihab and AF Mahdee, "Root and root canal morphology, study methods and classification", Journal Baghdad College Dentistry, Vol. 33 (No. 4), pp. 11-19, (2021).
9- S Sert, V Aslanalp and J Tanalp, "Investigation of the root canal configuration of mandibular permanent teeth in the Turkish population," International Endodontic Journal, Vol. 37 (No. 7), pp. 494-499, (2004).
10- Y Yang, B Wu, J Zeng and M Chen, "Classification and morphology of middle mesial canals of mandibular first molars in a southern Chinese subpopulation: a cone-beam computed tomographic study," BMC Oral Health, Vol. 20 (No. 1), pp. 358, (2020).
11- R Alroomy, F Elbaz, A Asiri, B Almulhim, M Kumari and T Gunaranjan, "Assessment of middle mesial canals in mandibular first molar using CBCT. An in vivo study," European Review for Medical and Pharmacological Sciences, Vol. 26 (No. 8), pp. 2861-2866, (2022).
12- M Tahmasbi, P Jalali, MK Nair, S Barghan and UP Nair, "Prevalence of Middle Mesial Canals and Isthmi in the Mesial Root of Mandibular Molars: An In Vivo Cone-beam Computed Tomographic Study," J Endod, Vol. 43 (No. 7), pp. 1080-1083, (2017).
13- X Hu, Z Huang, Z Huang, L Lei, M Cui and X Zhang, "Prevalence of isthmi in mesial roots and associated factors. An in vivo analysis," Surgical and Radiologic Anatomy, Vol. 41 (No. 7), pp. 815-822, (2019).
14- E Inaty, C Jabre, G Haddad, W Nehme, I Khalil and A Naaman, "Anatomical Investigation of Middle Mesial Canals of Mandibular Molars in a Middle Eastern Population: A Cross-sectional Cone-beam Computed Tomography Study," Journal of Contemporary Dental Practice, Vol. 21 (No. 8), pp. 910-915, (2020).
15- AA Al-Maswary, HW Almadhoon, A Elkhateb, A Hamdallah and E Halboub, "The Global Prevalence of Middle Mesial Canal in Mandibular First and Second Molars Assessed by Cone Beam Computed Tomography: A Systematic Review and Meta-Analysis," J Endod, Vol. 49 (No. 6), pp. 638-656, (2023).
16- F Pertek Hatipoğlu, G Mağat, O Hatipoğlu, N Taha, S Alfirjani and IZ Abidin, "Assessment of the Prevalence of Middle Mesial Canal in Mandibular First Molar: A Multinational Cross-sectional Study with Meta-analysis," J Endod, Vol. 49 (No. 5), pp. 549-558, (2023).
17- UA Bhatti, M Muhammad, MQ Javed and M Sajid, "Frequency of middle mesial canal in mandibular first molars and its association with various anatomic variables," Australian Endodontic Journal, Vol. 48 (No. 3), pp. 494-500, (2022).
18- EM Weinberg, AE Pereda, S Khurana, PP Lotlikar, C Falcon and C Hirschberg, "Incidence of Middle Mesial Canals Based on Distance between Mesial Canal Orifices in Mandibular Molars: A Clinical and Cone-beam Computed Tomographic Analysis." J Endod, Vol. 46 (No. 1), pp. 40-43, (2020).
19- CM Rwenyonyi, A Kutesa, LM Muwazi and W Buwembo, "Root and canal morphology of mandibular first and second permanent molar teeth in a Ugandan population," Odontology, Vol. 97 (No. 2), pp. 92-96, (2009).
20- K Gulabivala, TH Aung, A Alavi and YL Ng, "Root and canal morphology of Burmese mandibular molars," International Endodontic Journal, Vol. 34 (No. 5), pp. 359-370, (2001).
21- M Karapinar-Kazandag, BR Basrani and S Friedman, "The operating microscope-enhances detection and negotiation of accessory mesial canals in mandibular molars," J Endod, Vol. 36 (No. 8), pp. 1289–1294, (2010).
22- D Baugh and J Wallace, "Middle mesial canal of the mandibular first molar: A case report and literature review," J Endod, Vol. 30 (No. 3), pp. 185-186, (2004).
23- TP Cotton, TM Geisler, DT Holden, SA Schwartz and WC Schindler, "Endodontic applications of cone-beam volumetric tomography," J Endod, Vol. 33 (No. 9), pp. 1121-1132, (2007).
24- SK Sharma, SK Mudgal, K Thakur and R Gaur, "How to calculate sample size for observational and experimental nursing research studies," National Journal of Physiology, Pharmacy and Pharmacology, Vol. 10 (No. 1), pp. 1-8, (2020).
25- AK Khangura, S Gupta, A Gulati and S Singh, "Tooth decalcification using different decalcifying agents - A comparative study," Journal of Oral and Maxillofacialpathology, Vol. 25 (No. 3), pp. 463-469, (2021).
26- FJ Vertucci and RG Williams, "Root canal anatomy of the mandibular first molar," Journal of the New Jersey Dental Association, Vol. 45 (No. 3), pp. 27-28 passim, (1974).
27- FP Hatipoğlu, G Mağat, O Hatipoğlu, H Al-Khatib, AS Elatrash, IZ Abidin, T Kulczyk, MAM Alkhawas, GD Buchanan, M Kopbayeva, SBDS Surendar, MD S, MQ Javed, AA Madfa, S Bürklein, S Mimica, UB Bhatti, TI Maratovna, PJ Palma, JF Brochado Martins, "Assessment of the Prevalence of Radix Entomolaris and Distolingual Canal in Mandibular First Molars in 15 Countries: A Multinational Cross-sectional Study with Meta-analysis," J Endod, Vol. 49 (No. 10), pp. 1308-1318, (2023).
28- JNR Martins, C Nole, HF Ounsi, P Parashos, G Plotino, MF Ragnarsson, RR Aguilar, F Santiago, HC Seedat, W Vargas, M von Zuben, Y Zhang, H Alfawaz, MAM Alkhawas, Z Altaki, L Berti, C Boveda, I Cassim, A Chaniotis, D Flynn, JA Gonzalez, J Kottoor, A Monroe, EJNL Silva and MA Versiani, "Worldwide Assessment of the Mandibular First Molar Second Distal Root and Root Canal: A Cross-sectional Study with Meta-analysis," J Endod, Vol. 48 (No. 2), pp. 223-233, (2022).
29- MF Reyhani, S Rahimi and S Shahi, "Root canal therapy of a mandibular first molar with five root canals: a case report," Iran Endod J Fall, Vol. 2 (No. 3), pp. 110-112, (2007).
30- S Poorni, R Kumar and R Indira, "Canal complexity of a mandibular first molar," J Conserv Dent, Vol. 12 (No. 1), pp. 37-40, (2009).
31- G Chen, H Yao and C Tong, "Investigation of the root canal configuration of mandibular first molars in a Taiwan Chinese population," International Endodontic Journal, Vol. 42 (No. 11), pp. 1044-9, (2009).
32- J Kottoor, R Sudha and N Velmurugan, "Middle distal canal of the mandibular first molar: a case report and literature review," International Endodontic Journal, Vol. 43 (No. 8), pp. 714-722, (2010).
33- F Alnassar, Y Aldahman, A Altuwalah, A Aldafaas, R A-Sadhan and W Alnassar, "Assessment of the prevalence and configuration of middle distal canals in the mandibular molars in a Saudi subpopulation using Cone-Beam computed tomography," The Saudi Dental Journal, Vol. 34 (No. 2), pp. 150-154, (2022).
34- S Jain, "Mandibular first molar with three distal canals," Journal of Conservative Dentistry, Vol. 14 (No. 4), pp. 438-439, (2011).
35- JYY Pan, A Parolia, SR Chuah, S Bhatia, S Mutalik and A Pau, "Root canal morphology of permanent teeth in a Malaysian subpopulation using cone-beam computed tomography," BMC Oral Health, Vol. 19 (No. 1), pp. 14, (2019).
36- ME Kolsuz, C Evli, U Aksoy, M Koohnavard, S Aksoy and K Orhan, "Influence of voxel size and filter type on detecting vertical root fracture using CBCT," Australian Endodontic Journal, Vol. 49, pp. 439-446, (2023).
37- OB Dogan, H Boyacioglun and D Goksulak, "Machine learning assessment of dental age classification based on CBCT images a different approach," Dento Maxillo Facial Radiology, Vol. 53 (No. 1), pp. 67-73, (2024).
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| Issue | Vol 13 No 3 (2026) | |
| Section | Original Article(s) | |
| DOI | https://doi.org/10.18502/fbt.v13i3.22737 | |
| Keywords | ||
| second distal canal histological sectioning CBCT. | ||
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How to Cite
1.
Al-Huwaizi HF, Mutlag LS. The Prevalence of Second Distal Canals in the Mandibular First Molars: A Histological and Cone Beam Computed Tomography Study. Frontiers Biomed Technol. 2026;13(3):649-658.
