Technical Quality of Root Canal Fillings Performed by Preclinical Dental Students: A Randomized Crossover Study

Muhammed Ayhan; Asım Ünlü; Damla Erkal

doi:10.7126/cumudj.1859858

TR EN

Preklinik Diş Hekimliği Öğrencileri Tarafından Yapılan Kök Kanal Dolgularının Teknik Kalitesi: Randomize Çapraz Tasarımlı Bir Çalışma

Abstract

Öz Amaç: Bu çalışma, çekilmiş insan dişleri üzerinde farklı enstrümantasyon teknikleri kullanılarak lisans öğrencileri tarafından yapılan kök kanal dolgularının (KKD) teknik kalitesini değerlendirmeyi amaçladı. Gereç ve Yöntem: Toplam 200 daimi insan dişi (72 kanin, 62 maksillar birinci premolar ve 66 mandibular molar), öğrenciler tarafından el enstrümantasyonu (EE) (n = 100) veya rotary enstrümantasyon (RE) (n = 100) sonrası dolduruldu. Genel teknik kalite, dolgu uzunluğu, densite, koniklik (taper), iyatrojenik hatalar ile preparasyon ve obturasyon süreleri; enstrümantasyon tekniği ve diş tipine göre değerlendirildi. Gruplar arası karşılaştırmalar genelleştirilmiş tahmin denklemleri (GTD) kullanılarak analiz edildi; preparasyon ve obturasyon süreleri ise lineer karma modeller ile değerlendirildi. Bulgular: Toplam 200 dişin 76’sı (%38,0) kabul edilebilir olarak sınıflandırıldı. RE, EE’ye kıyasla kabul edilebilir kök kanal dolgusu (KKD) kalitesine ulaşma olasılığını anlamlı düzeyde artırdı (OR = 4,03; %95 GA: 1,54–10,53; p = 0,004) ve enstrümantasyon tekniği ile diş tipi arasında anlamlı bir etkileşim saptandı (p = 0,004). Ham oranlar RE grubunda EE grubuna göre daha yüksekti (%45,0’a karşı %31,0); en büyük fark molarlarda görüldü (%47,1’e karşı %18,8; p = 0,015), ancak alt grup karşılaştırmalarında kaninlerde (%69,4’e karşı %50,0; p = 0,093) ve premolarlarda (%13,3’e karşı %21,9; p = 0,379) anlamlı fark izlenmedi. RE, uzunluk ve koniklik açısından daha iyi sonuçlarla ilişkiliydi (sırasıyla p = 0,002 ve p < 0,001), buna karşın yoğunluk açısından anlamlı fark yoktu (p = 0,095). İyatrojenik hatalar dişlerin %14,5’inde görüldü ve teknikler arasında anlamlı farklılık göstermedi (p = 0,159); bununla birlikte, premolar ve molarlarda kaninlere göre daha sık gözlendi. Lineer karma modeller, RE ile preparasyon ve obturasyon sürelerinin anlamlı derecede daha kısa olduğunu gösterdi (her ikisi için p < 0,001). Sonuç: RE, EE’ye kıyasla kök kanal dolgularının genel teknik kalitesini artırdı ve preparasyon ile obturasyon sürelerini anlamlı derecede azalttı; en belirgin fayda molar dişlerde gözlenirken, iyatrojenik hata insidansı teknikler arasında benzerdi.

Keywords

Technical Quality of Root Canal Fillings Performed by Preclinical Dental Students: A Randomized Crossover Study

Abstract

Abstract Objectives: This study aimed to evaluate the technical quality of root canal fillings (RCFs) performed by undergraduate students using different instrumentation techniques on extracted human teeth. Materials and Methods: A total of 200 permanent human teeth (72 canines, 62 maxillary first premolars, and 66 mandibular molars) were obturated by students following hand instrumentation (HI) (n = 100) or rotary instrumentation (RI) (n = 100). Overall technical quality, filling length, density, taper, iatrogenic errors, and preparation and obturation times were assessed according to instrumentation technique and tooth type. Group comparisons were analysed using generalized estimating equations (GEE), and preparation and obturation times were analysed using linear mixed models. Results: Overall, 76 of 200 teeth (38.0%) were classified as acceptable. RI significantly increased the odds of acceptable RCF quality versus HI (OR = 4.03, 95% CI: 1.54–10.53; p = 0.004), with a significant instrumentation-by-tooth-type interaction (p = 0.004). Crude proportions were higher with RI than HI (45.0% vs. 31.0%), with the largest difference in molars (47.1% vs. 18.8%; p = 0.015), while subgroup differences were not significant in canines (69.4% vs. 50.0%; p = 0.093) or premolars (13.3% vs. 21.9%; p = 0.379). RI was associated with better length and taper (p = 0.002 and p < 0.001, respectively), whereas density did not differ significantly (p = 0.095). Iatrogenic errors occurred in 14.5% of teeth and were not significantly different between techniques (p = 0.159), although they were more frequent in premolars and molars than in canines. Linear mixed models showed significantly shorter preparation and obturation times with RI (both p < 0.001). Conclusions: RI improved the overall technical quality of RCFs and significantly reduced preparation and obturation times compared with HI, with the greatest benefit observed in molar teeth, while the incidence of iatrogenic errors was comparable between techniques.

Keywords

References

1. Ng YL, Mann V, Rahbaran S, Lewsey J, Gulabivala K. Outcome of primary root canal treatment: systematic review of the literature - part 1. Effects of study characteristics on probability of success. Int Endod J 2007;40(12):921-939.
2. Ng YL, Mann V, Rahbaran S, Lewsey J, Gulabivala K. Outcome of primary root canal treatment: systematic review of the literature -- Part 2. Influence of clinical factors. Int Endod J 2008;41(1):6-31.
3. Quality guidelines for endodontic treatment: consensus report of the European Society of Endodontology. Int Endod J 2006;39(12):921-930.
4. Elsayed RO, Abu-Bakr NH, Ibrahim YE. Quality of root canal treatment performed by undergraduate dental students at the University of Khartoum, Sudan. Aust Endod J 2011;37(2):56-60.
5. Rafeek RN, Smith WA, Mankee MS, Coldero LG. Radiographic evaluation of the technical quality of root canal fillings performed by dental students. Aust Endod J 2012;38(2):64-69.
6. Miçooğulları Kurt S, Kandemir Demirci G, Serefoglu B, Kaval ME, Güneri P, Çalışkan MK. Quality of root canal treatment performed by undergraduate students using nickel-titanium reciprocating versus hand instruments. J Dent Educ 2022;86(12):1662-1670.
7. Bezerra VGL, Ferreira AL, Fernandes VDG, Teixeira-da-Silva D, Paranhos LR, Matos FS. Technical quality of root fillings performed by undergraduate dental students in single-canal teeth: a 10-year retrospective study. Eur J Dent Educ 2024;28(4):1052-1057.
8. Khabbaz MG, Protogerou E, Douka E. Radiographic quality of root fillings performed by undergraduate students. Int Endod J 2010;43(6):499-508.

9. Celik D, Taşdemir T, Er K. Comparative study of 6 rotary nickel-titanium systems and hand instrumentation for root canal preparation in severely curved root canals of extracted teeth. J Endod 2013;39(2):278-282.
10. Ahmed A, Foschi F, Duncan HF, McColl E. Investigating the technical quality of undergraduate endodontic treatment in a primary care-based dental school. Br Dent J 2024.
11. Ayhan M, Yıldız T, Protogerou E. Evaluation and comparison of mandibular molar root canal filling quality performed by undergraduate preclinical dental students. Sci Rep 2025;15(1):15149.
12. Madfa AA, Almansour MI, Al-Zubaidi SM, Albaqawi AH, Almeshari SA, Khawshhal AA, et al. Assessment of the quality of root canal fillings performed on extracted teeth by undergraduate dental students in a sample from Saudi Arabia. BMC Med Educ 2024;24(1):157.
13. Román-Richon S, Faus-Matoses V, Alegre-Domingo T, Faus-Llácer VJ. Radiographic technical quality of root canal treatment performed ex vivo by dental students at Valencia University Medical and Dental School, Spain. Med Oral Patol Oral Cir Bucal 2014;19(1):e93-97.
14. Eleftheriadis GI, Lambrianidis TP. Technical quality of root canal treatment and detection of iatrogenic errors in an undergraduate dental clinic. Int Endod J 2005;38(10):725-734.
15. Fong W, Heidarifar O, Killough S, Lappin MJ, El Karim IA. An audit on technical quality of root fillings performed by undergraduate students. Int Endod J 2018;51 Suppl 3:e197-e203.
16. Peters OA. Current challenges and concepts in the preparation of root canal systems: a review. J Endod 2004;30(8):559-567.
17. Ayhan M, Aykanat B. Ex vivo accuracy of three electronic root canal length measurement devices: X-smart pro+, root ZX mini, and propex pixi. BMC Oral Health. 2025;25(1):1072.
18. Ricucci D, Langeland K. Apical limit of root canal instrumentation and obturation, part 2. A histological study. Int Endod J 1998;31(6):394-409.
19. Al-Anesi MS, AlKhawlani MM, Alkheraif AA, Al-Basmi AA, Alhajj MN. An audit of root canal filling quality performed by undergraduate pre-clinical dental students, Yemen. BMC Med Educ 2019;19(1):350.
20. Sonntag D, Guntermann A, Kim SK, Stachniss V. Root canal shaping with manual stainless steel files and rotary Ni-Ti files performed by students. Int Endod J 2003;36(4):246-255.
21. Jungnickel L, Kruse C, Vaeth M, Kirkevang LL. Quality aspects of ex vivo root canal treatments done by undergraduate dental students using four different endodontic treatment systems. Acta Odontol Scand 2018;76(3):169-174.
22. Ayhan M, Yıldız T. Technical quality of root canal treatment performed by undergraduate students with endodontic rotary files and hand files. Cumhuriyet Dent J 2025;28(4):526-532.
23. Abu-Tahun I, Al-Rabab'ah MA, Hammad M, Khraisat A. Technical quality of root canal treatment of posterior teeth after rotary or hand preparation by fifth year undergraduate students, The University of Jordan. Aust Endod J 2014;40(3):123-130.
24. Parashos P, Messer HH. Rotary NiTi instrument fracture and its consequences. J Endod 2006;32(11):1031-1043.
25. Zupanc J, Vahdat-Pajouh N, Schäfer E. New thermomechanically treated NiTi alloys - a review. Int Endod J 2018;51(10):1088-1103.
26. AlRahabi MK. Evaluation of complications of root canal treatment performed by undergraduate dental students. Libyan J Med 2017;12(1):1345582.
27. Matoug-Elwerfelli M, Abdou A, Almutairi W, Alhuthayli M, Aloyaynaa S, Almohareb R. Radiographic assessment of endodontic mishaps in an undergraduate student clinic: a 2-year retrospective study. PeerJ 2022;10:e13858.
28. Hendi SS, Karkehabadi H, Eskandarloo A. Iatrogenic errors during root canal instrumentation performed by dental students. Iran Endod J 2018;13(1):126-131.
29. Vaudt J, Bitter K, Neumann K, Kielbassa AM. Ex vivo study on root canal instrumentation of two rotary nickel-titanium systems in comparison to stainless steel hand instruments. Int Endod J 2009;42(1):22-33.
30. Kummer TR, Calvo MC, Cordeiro MM, de Sousa Vieira R, de Carvalho Rocha MJ. Ex vivo study of manual and rotary instrumentation techniques in human primary teeth. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2008;105(4):e84-92.

Details

Primary Language

English

Subjects

Endodontics

Journal Section

Research Article

Authors

Muhammed Ayhan
0000-0003-0264-2149
Türkiye

Asım Ünlü
0009-0001-0474-6550
Türkiye

Damla Erkal ^*
0000-0001-8319-6974
Türkiye

Publication Date

July 1, 2026

Submission Date

January 9, 2026

Acceptance Date

March 17, 2026

Published in Issue

Year 2026 Volume: 29 Number: 2

DOI

https://doi.org/10.7126/cumudj.1859858

IZ

https://izlik.org/JA37NF72XE

Cite

RIS / Bibtex

APA

Ayhan, M., Ünlü, A., & Erkal, D. (2026). Technical Quality of Root Canal Fillings Performed by Preclinical Dental Students: A Randomized Crossover Study. Cumhuriyet Dental Journal, 29(2), 327-336. https://doi.org/10.7126/cumudj.1859858

AMA

1.Ayhan M, Ünlü A, Erkal D. Technical Quality of Root Canal Fillings Performed by Preclinical Dental Students: A Randomized Crossover Study. Cumhuriyet Dent J. 2026;29(2):327-336. doi:10.7126/cumudj.1859858

Chicago

Ayhan, Muhammed, Asım Ünlü, and Damla Erkal. 2026. “Technical Quality of Root Canal Fillings Performed by Preclinical Dental Students: A Randomized Crossover Study”. Cumhuriyet Dental Journal 29 (2): 327-36. https://doi.org/10.7126/cumudj.1859858.

EndNote

Ayhan M, Ünlü A, Erkal D (July 1, 2026) Technical Quality of Root Canal Fillings Performed by Preclinical Dental Students: A Randomized Crossover Study. Cumhuriyet Dental Journal 29 2 327–336.

IEEE

[1]M. Ayhan, A. Ünlü, and D. Erkal, “Technical Quality of Root Canal Fillings Performed by Preclinical Dental Students: A Randomized Crossover Study”, Cumhuriyet Dent J, vol. 29, no. 2, pp. 327–336, July 2026, doi: 10.7126/cumudj.1859858.

ISNAD

Ayhan, Muhammed - Ünlü, Asım - Erkal, Damla. “Technical Quality of Root Canal Fillings Performed by Preclinical Dental Students: A Randomized Crossover Study”. Cumhuriyet Dental Journal 29/2 (July 1, 2026): 327-336. https://doi.org/10.7126/cumudj.1859858.

JAMA

1.Ayhan M, Ünlü A, Erkal D. Technical Quality of Root Canal Fillings Performed by Preclinical Dental Students: A Randomized Crossover Study. Cumhuriyet Dent J. 2026;29:327–336.

MLA

Ayhan, Muhammed, et al. “Technical Quality of Root Canal Fillings Performed by Preclinical Dental Students: A Randomized Crossover Study”. Cumhuriyet Dental Journal, vol. 29, no. 2, July 2026, pp. 327-36, doi:10.7126/cumudj.1859858.

Vancouver

1.Muhammed Ayhan, Asım Ünlü, Damla Erkal. Technical Quality of Root Canal Fillings Performed by Preclinical Dental Students: A Randomized Crossover Study. Cumhuriyet Dent J. 2026 Jul. 1;29(2):327-36. doi:10.7126/cumudj.1859858