Bacterial removal in flattened root canals with different tapers of ProDesign Logic single-file system




Biofilms; Endodontics; Enterococcus faecalis; Root canal preparation.


Objective: This study evaluated the bacterial removal in flattened root canals after preparation with different tapers of ProDesign Logic instruments. Methodology: Fifty-five mandibular incisors with flattened root canals were contaminated with a pure culture of Enterococcus faecalis ATCC 29212 for 21 days at 37ºC. Root canals preparation was performed using ProDesign Logic and 0.9% sterile saline solution for irrigation. The specimens were randomly allocated to three experimental groups (n = 15) according to the taper of the instrument used: 25.03, 25.04, or 25.06. Intracanal bacteriological samples were taken before (S1) and after (S2) preparation and the number of colony-forming units per milliliter (CFU/mL) was calculated. Differences in bacterial counts before and after treatment, within each group, were analyzed by the paired t-test. Groups were compared by ANOVA with a post hoc test. The level of significance was set at p <0.05. Results: Mature biofilm formation was confirmed at root canal walls by scanning electron microscopy. Bacterial colonies were significantly reduced in all experimental groups at S2 compared to S1 (p <0.001). No significant difference was observed between groups regarding the percentage of bacterial reduction (p >0.05). Conclusion: Preparation of flattened root canals using ProDesign Logic instruments with tapers of 0.03, 0.04 and 0.06 resulted in similar planktonic and bacterial biofilm reduction. None of the instruments rendered root canals completely free of bacteria.


Alcalde, M. P. , Duarte, M. A. H., Bramante, C. M., et al. (2018). Torsional Fatigue Resistance of Pathfinding Instruments Manufactured from Several Nickel-Titanium Alloys. International Endodontic Journal, 51, 697–704.

Alves, F. R. F., Rôças, I. N., Almeida, B. M., et al. (2012). Quantitative Molecular and Culture Analyses of Bacterial Elimination in Oval-Shaped Root Canals by a Single-File Instrumentation Technique. International Endodontic Journal, 45, 871–877.

Azim, A. A., Wang, H. H., Tarrosh, M., Azim, K. A., & Piasecki, L. (2018a). Comparison between Single-File Rotary Systems: Part 1—Efficiency, Effectiveness, and Adverse Effects in Endodontic Retreatment. Journal of Endodontics, 44, 1720–1724.

Azim, A. A., Tarrosh, M., Azim, K. A., & Piasecki, L. (2018b). Comparison between Single-File Rotary Systems: Part 2—The Effect of Length of the Instrument Subjected to Cyclic Loading on Cyclic Fatigue Resistance. Journal of Endodontics, 44, 1837–1842.

Bürklein, S. & Schäfer, E. (2015). Minimally Invasive Endodontics. Quintessence International, 46, 119–124.

Carvalho M. C., Zuolo M. L., Arruda-Vasconcelos R., et al. (2019). Effectiveness of XP-Endo Finisher in the Reduction of Bacterial Load in Oval-Shaped Root Canals. Brazilian Oral Research, 33, 1–8.

ElAyouti, A., Chu, A-L., Kimionis, I., et al. (2008). Efficacy of Rotary Instruments with Greater Taper in Preparing Oval Root Canals. International Endodontic Journal, 41, 1088–1092.

Machado, M. E. D. L, Bichels Sapia, L. A., Cai S., Rosa Martins, G. H., & Nabeshima, C. K. (2010). Comparison of Two Rotary Systems in Root Canal Preparation Regarding Disinfection. Journal of Endodontics, 36, 1238–1240.

Machado, M. E. L., Nabeshima, C. K., Leonardo, M. F. P., et al. (2013). Influence of Reciprocating Single-File and Rotary Instrumentation on Bacterial Reduction on Infected Root Canals. International Endodontic Journal, 46, 1083–1087.

Molander, A. & Dahlén, G. (2003). Evaluation of the Antibacterial Potential of Tetracycline or Erythromycin Mixed with Calcium Hydroxide as Intracanal Dressing against Enterococcus Faecalis in Vivo. Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontics, 96, 744–750.

Moshari, A., Akhlaghi, N., Rahimifard, N., & Darmiani, S. (2015). Reduction of Enterococcus Faecalis in Curved Root Canals after Various Sizes and Tapers of Canal Preparation. Journal of Conservative Dentistry, 18, 306–309.

Nakamura, V. C., Cai S., Candeiro G. T. M., et al. (2013). Ex Vivo Evaluation of the Effects of Several Root Canal Preparation Techniques and Irrigation Regimens on a Mixed Microbial Infection. International Endodontic Journal, 46, 217–224.

Neves, M. A. S., Provenzano, J. C., Rôças, I. N., & Siqueira, J. F. (2016). Clinical Antibacterial Effectiveness of Root Canal Preparation with Reciprocating Single-Instrument or Continuously Rotating Multi-Instrument Systems. Journal of Endodontics, 42, 25–29.

Paraskevopoulou, M. T. & Khabbaz, M. G. (2016). Influence of Taper of Root Canal Shape on the Intracanal Bacterial Reduction. The Open Dentistry Journal, 10, 568–574.

Pérez, A. R., Alves, F. R. F., Marceliano-Alves, M. F., et al. (2018). Effects of Increased Apical Enlargement on the Amount of Unprepared Areas and Coronal Dentine Removal: A Micro-Computed Tomography Study. International Endodontic Journal, 51, 684–690.

Pérez Alejandro, R., Ricucci, D., Vieira, G. C. S., et al. (2020). Cleaning, Shaping, and Disinfecting Abilities of 2 Instrument Systems as Evaluated by a Correlative Micro–Computed Tomographic and Histobacteriologic Approach. Journal of Endodontics, 46, 846–857.

Pinto, J. C., Torres, F. F. E., Santos Junior, A. O., et al. (2021). Influence of Voxel Size on Micro-CT Analysis of Debris after Root Canal Preparation. Brazilian Oral Research, 35(13), 35:e008.

Ricucci, D. & Siqueira, J. F. (2010). Biofilms and Apical Periodontitis: Study of Prevalence and Association with Clinical and Histopathologic Findings. Journal of Endodontics, 36, 1277–1288.

Rôças, I., Siqueira, J., Santos, K. (2004). Association of Enterococcus Faecalis with Different Forms of Periradicular. Journal of Endodontics, 30, 315–320.

Silva, E. J. N. L., Nejaim, Y., Silva, A. I. V., et al. (2014). Evaluation of Root Canal Configuration of Maxillary Molars in a Brazilian Population Using Cone-Beam Computed Tomographic Imaging: An in Vivo Study. Journal of Endodontics, 40, 173–176.

Siqueira, J. F., Alves, F. R. F., Almeida, B. M., Machado de Oliveira, J. C., Rôças, I. N. (2010). Ability of Chemomechanical Preparation with Either Rotary Instruments or Self-Adjusting File to Disinfect Oval-Shaped Root Canals. Journal of Endodontics, 36, 1860–1865.

Siqueira, J. F. & Rôças, I. N. (2004). Polymerase Chain Reaction-Based Analysis of Microorganisms Associated with Failed Endodontic Treatment. Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontics, 97, 85–94.

Siqueira, Junior J. F., Rôças, I. N., Marceliano-Alves, M. F., Pérez, A. R., & Ricucci, D. (2018). Unprepared Root Canal Surface Areas: Causes, Clinical Implications, and Therapeutic Strategies. Brazilian Oral Research, 32, 1–19.

Tay, F. R., Gu, L. sha., Schoeffel, G. J., et al. (2010). Effect of Vapor Lock on Root Canal Debridement by Using a Side-Vented Needle for Positive-Pressure Irrigant Delivery. Journal of Endodontics, 36, 745–750.

Tüfenkçi, P. & Yılmaz, K. (2020). The Effects of Different Endodontic Access Cavity Design and Using XP-Endo Finisher on the Reduction of Enterococcus Faecalis in the Root Canal System. Journal of Endodontics, 46, 419–424.




How to Cite

SANDINI, V.; GODOY, V.; PRADO, M. C.; FERREIRA, R.; DE-JESUS-SOARES, A.; FROZONI, M. Bacterial removal in flattened root canals with different tapers of ProDesign Logic single-file system. Research, Society and Development, [S. l.], v. 10, n. 9, p. e5910917701, 2021. DOI: 10.33448/rsd-v10i9.17701. Disponível em: Acesso em: 26 oct. 2021.



Health Sciences