An in vitro study on the efficacy of removing calcium hydroxide from curved root canal systems in root canal therapy

Abstract

Using citric acid in combination with ultrasonic rinsing helps flush out root canals prior to completing treatment. Calcium hydroxide, Ca(OH)₂, is used to eliminate microbes from root canals during treatment. However, residual Ca(OH)₂ left behind once treatment is complete can reduce the effectiveness of sealants and weaken dentin bonds. Hui Yang and Tao Hu at Sichuan University in Chengdu, China, and co- trialled novel ways of removing Ca(OH)₂ from curved root canal systems. Using synthetic root canal models and extracted human teeth, the team used different rinsing chemicals and techniques to clean root canals of different shapes. They found that citric acid was most effective, particularly when combined with ultrasonic rinsing. This technique agitated and loosened residues left in the root canal wall, allowing for a cleaner finish.

Keywords

calcium hydroxide / curved root canal system / irrigation / removal

References

[1] Provenzano JC, Rôças IN, Tavares LF. Short-chain fatty acids in infected root canals of teeth with apical periodontitis before and after treatment. J Endod, 2015, 41(6): 831-835.

[2] Mohammadi Z, Dummer PM. Properties and applications of calcium hydroxide in endodontics and dental traumatology. Int Endod J, 2011, 44(8): 697-730.

[3] Marinho AC, Polay AR, Gomes BP. Accuracy of turbidimetric limulus amebocyte lysate assay for the recovery of endotoxin interacted with commonly used antimicrobial agents of endodontic therapy. J Endod, 2015, 41(10): 1653-1659.

[4] Tavares WL, de Brito LC, Henriques LC. Effects of calcium hydroxide on cytokine expression in endodontic infections. J Endod, 2012, 38(10): 1368-1371.

[5] Pereira MS, Rossi MA, Cardoso CR. Cellular and molecular tissue response to triple antibiotic intracanal dressing. J Endod, 2014, 40(4): 499-504.

[6] Simcock RM, Hicks ML. Delivery of calcium hydroxide: comparison of four filling techniques. J Endod, 2006, 32(7): 680-682.

[7] Kim SK, Kim YO. Influence of calcium hydroxide intracanal medication on apical seal. Int Endod J, 2002, 35(7): 623-628.

[8] Calt S, Serper A. Dentinal tubule penetration of root canal sealers after root canal dressing with calcium hydroxide. J Endod, 1999, 25(6): 431-433.

[9] Margelos J, Eliades G, Verdelis C. Interaction of calcium hydroxide with zinc oxide-eugenol type sealers: a potential clinical problem. J Endod, 1997, 23(1): 43-48.

[10] Erdemir A, Hale Ari, Güngüneş H. Effect of medications for root canal treatment on bonding to root canal dentin. J Endod, 2004, 30(2): 113-116.

[11] Zorzin J, Wießner J, Wießner T. Removal of radioactively marked calcium hydroxide from the root canal: influence of volume of irrigation and activation. J Endod, 2016, 42(4): 637-640.

[12] Rödig T, Vogel S, Zapf A. Efficacy of different irrigants in the removal of calcium hydroxide from root canals. Int Endod J, 2010, 43(6): 519-527.

[13] Sağsen B, Ustün Y, Aslan T. The effect of peracetic acid on removing calcium hydroxide from the root canals. J Endod, 2012, 38(9): 1197-1201.

[14] Capar ID, Ozcan E, Arslan H. Effect of different final irrigation methods on the removal of calcium hydroxide from an artificial standardized groove in the apical third of root canals. J Endod, 2014, 40(3): 451-454.

[15] Kuştarcı A, Er K, Siso SH. Efficacy of laser-activated irrigants in calcium hydroxide removal from the artificial grooves in root canals: an ex vivo study. Photomed Laser Surg, 2016, 34(5): 205-210.

[16] Wigler R, Dvir R, Weisman A et al. Efficacy of XP-endo finisher files in the removal of calcium hydroxide paste from artificial standardized grooves in the apical third of oval root canals. Int Endod J 2016; doi:10.1111/iej.12668 (Epub ahead of print).

[17] Wiseman A, Cox TC, Paranjpe A. Efficacy of sonic and ultrasonic activation for removal of calcium hydroxide from mesial canals of mandibular molars: a microtomographic study. J Endod, 2011, 37(2): 235-238.

[18] De-Deus G. Research that matters-root canal filling and leakage studies. Int Endod J, 2012, 45(12): 1063-1064.

[19] Schäfer E, Erler M, Dammaschke T. Comparative study on the shaping ability and cleaning efficiency of rotary Mtwo instruments. Part 2. Cleaning effectiveness and shaping ability in severely curved root canals of extracted teeth. Int Endod J, 2006, 39(3): 203-212.

[20] Townsend C, Maki J. An in vitro comparison of new irrigation and agitation techniques to ultrasonic agitation in removing bacteria from a simulated root canal. J Endod, 2009, 35(7): 1040-1043.

[21] Schneider SW. A comparison of canal preparations in straight and curved root canals. Oral Surg Oral Med Oral Pathol, 1971, 32(2): 271-275.

[22] Gao Y, Haapasalo M, Shen Y. Development and validation of a three-dimensional computational fluid dynamics model of root canal irrigation. J Endod, 2009, 35(9): 1282-1287.

[23] Elsherief SM, Zayet MK, Hamouda IM. Cone-beam computed tomography analysis of curved root canals after mechanical preparation with three nickel-titanium rotary instruments. J Biomed Res, 2013, 27(4): 326-335.

[24] Ma JZ, Shen Y, Al-Ashaw AJ. Micro-computed tomography evaluation of the removal of calcium hydroxide medicament from C-shaped root canals of mandibular second molars. Int Endod J, 2015, 48(4): 333-341.

[25] Goode N, Khan S, Eid AA. Wall shear stress effects of different endodontic irrigation techniques and systems. J Dent, 2013, 41(7): 636-641.

[26] Ballal NV, Kumar SR, Laxmikanth HK. Comparative evaluation of different chelators in removal of calcium hydroxide preparations from root canals. Aust Dent J, 2012, 57(3): 344-348.

[27] Rödig T, Hirschleb M, Zapf A. Comparison of ultrasonic irrigation and RinsEndo for the removal of calcium hydroxide and Ledermix paste from root canals. Int Endod J, 2011, 44(12): 1155-1161.

[28] Alturaiki S, Lamphon H, Edrees H. Efficacy of 3 different irrigation systems on removal of calcium hydroxide from the root canal: a scanning electron microscopic study. J Endod, 2015, 41(1): 97-101.

[29] Basrani B, Haapasalo M. Update on endodontic irrigating solutions. Endod Topics, 2012, 27(1): 74-102.

[30] Ethem Yaylali I, Kececi AD, Ureyen Kaya B. Ultrasonically activated irrigation to remove calcium hydroxide from apical third of human root canal system: a systematic review of in vitro studies. J Endod, 2015, 41(10): 1589-1599.

[31] Ma JZ, Shen Y, Yang Y. In vitro study of calcium hydroxide removal from mandibular molar root canals. J Endod, 2015, 41(4): 553-558.

[32] Topçuoğlu HS, Düzgün S, Ceyhanlı KT. Efficacy of different irrigation techniques in the removal of calcium hydroxide from a simulated internal root resorption cavity. Int Endod J, 2015, 48(4): 309-316.

[33] Boutsioukis C, Verhaagen B, Walmsley AD. Measurement and visualization of file-to-wall contact during ultrasonically activated irrigation in simulated canals. Int Endod J, 2013, 46(11): 1046-1055.

[34] Hülsmann M. Effects of mechanical instrumentation and chemical irrigation on the root canal dentin and surrounding tissues. Endod Topics, 2013, 29(1): 55-86.

[35] Chou K, George R, Walsh LJ. Effectiveness of different intracanal irrigation techniques in removing intracanal paste medicaments. Aust Endod J, 2014, 40(1): 21-25.