13. endodontic irrigants.pptxbhhhjjhghbbg

Good

1. ENDODONTIC IRRIGANTS AND IRRIGATION Dr AHMED ALI KHAN

2. Contents Introduction Ideal properties of irrigating solutions Goals of irrigation Classification of irrigating solutions Individual irrigants Sodium hypochlorite( naocl ) Hydrogen peroxide (3% h 2 o 2 ) Iodine compounds Chlorhexidine gluconate Organic acids - Edta -Citric acid

3. Urea Physiologic saline solution Mtad ozone Combination of irrigants Selection of irrigants Methods of irrigation Various delivery systems for irrigation Complications during irrigation

4. Selection of irrigants New modalities of irrigation Summary Conclusion References

5. INTRODUCTION The effectiveness of endodontic files, rotary instrumentation, irrigating solutions, and chelating agents to clean, shape, and disinfect root canals underpins the success, longevity, and reliability of modern endodontic treatments.

6. Elimination of microorganisms from infected root canals is a complicated task. The chances of a favourable outcome with root canal treatment are significantly higher if infection is eradicated effectively before the root canal system is obturated . However, if microorganisms persist at the time of obturation, or if they penetrate into the canal after obturation, there is a high risk of treatment failure.

7. Numerous measures have been described to reduce the number of microorganisms in the root canal system, including the use of various instrumentation techniques, irrigation regimens, and intracanal medicaments. The use of chemical agents during instrumentation to completely clean all aspects of the root canal system is central to successful endodontic treatment .

8. Irrigation is complementary to instrumentation in facilitating the removal of pulp tissue and/or microorganisms. Irrigation dynamics plays an important role; the effectiveness of irrigation depends on the working mechanism(s) of the irrigant and the ability to bring the irrigant in contact with the microorganisms and tissue debris in the root canal.

9. GOALS OF IRRIGATION Irrigation in Endodontics Dent Clin N Am 54 (2010) 291–312

10. GOALS OF IRRIGATION Irrigation in Endodontics Dent Clin N Am 54 (2010) 291–312

11. Ideal Requirement of Root Canal Irrigants Review Article Newer Root Canal Irrigants in Horizon: A Review International Journal of Dentistry Volume 2011, Article ID 851359, 9 pages

12. Ideal Requirement of Root Canal Irrigants Review Article Newer Root Canal Irrigants in Horizon: A Review International Journal of Dentistry Volume 2011, Article ID 851359, 9 pages

13. Classification TAGGER 1979

14. Classification STOCK

15. Classification WALTON

16. Classification

17. Classification

18. INDIVIDUAL IRRIGANTS

19. Sodium hypochlorite

20. Mechanism of action NaOCl ionizes in water into Na and the hypochlorite ion, ( Ocl ), establishing an equilibrium with hypochlorous acid ( HOCl ). At acidic and neutral pH, chlorine exists predominantly as HOCl , whereas at high pH of 9 and above, OCl predominates. Dent Clin N Am 54 (2010) 291–312, Irrigation in Endodontics

21. Hypochlorous acid is responsible for the antibacterial activity; the OCl ion is less effective than the undissolved HOCl . Hypochloric acid disrupts several vital functions of the microbial cell, resulting in cell death.

22. CONCENTRATION OF NAOCL As Dakin’s original 0.5% sodium hypochlorite solution was designed to treat open (burnt) wounds, it was surmised that in the confined area of a root canal system, higher concentrations should be used, as they would be more efficient than Dakin’s solution. The antibacterial effectiveness and tissue dissolution capacity of aqueous hypochlorite is a function of its concentration, but so is its toxicity. Root Canal Irrigants, JOE — Volume 32, Number 5, May 2006

23. Root Canal Irrigants, JOE — Volume 32, Number 5, May 2006 Furthermore, a 5.25% solution significantly decreases the elastic modulus and flexural strength of human dentin compared to physiologic saline, while a 0.5% solution does not. This is most likely because of the proteolytic action of concentrated hypochlorite on the collagen matrix of dentin.

24. From in vitro observations, it would appear that a 1% NaOCl solution should suffice to dissolve the entire pulp tissue in the course of an endodontic treatment session. The effects of temperature on sodium hypochlorite short-term stability, pulp dissolution capacity, and antimicrobial efficacy. J Endod 2005;31:669 –71.

25. It must be realized that during irrigation, fresh hypochlorite consistently reaches the canal system, and concentration of the solution may thus not play a decisive role. Unclean areas may be a result of the inability of solutions to physically reach these areas rather than their concentration. Root Canal Irrigants, JOE — Volume 32, Number 5, May 2006

26. Smear layer unable to remove the smear layer by itself, as it dissolves only organic material. Irrigation in Endodontics , Dent Clin N Am 54 (2010) 291–312

27. The use of NaOCl dissolves the collagen, leaving the entrances to the dentinal tubules more open and exposed. One important aspect related to currently available irrigating solutions, i.e. EDTA and citric acid, is that they strongly interact with sodium hypochlorite. Both citric acid and EDTA immediately reduce the available chlorine in solution, rendering the sodium hypochlorite irrigant ineffective on bacteria and necrotic tissue. Hence, citric acid or EDTA should never be mixed with sodium hypochlorite. International Endodontic Journal, 38, 285–290, 2005 ª 2005 International Endodontic Journal Goldman et al. 1982, Baumgartner & Mader 1987

28. Efficacy Reactive chlorine in aqueous solution at body temperature can, take two forms: hypochlorite ( OCl ) or hypochlorous acid ( HOCl ). The concentration of these can be expressed as available chlorine by determining the electrochemical equivalent amount of elemental chlorine. Root Canal Irrigants, JOE — Volume 32, Number 5, May 2006

29. The state of available chlorine is depending on the pH of the solution. Above a pH of 7.6, the predominant form is hypochlorite, below this value it is hypochlorous acid. Both forms are extremely reactive oxidizing agents. Pure hypochlorite solutions as they are used in endodontics have a pH of 12, and thus the entire available chlorine is in the form of hypochlorite. Root Canal Irrigants, JOE — Volume 32, Number 5, May 2006

30. ph One way to increase the efficacy of hypochlorite solutions is to lower their pH. It has also been surmised that such solutions would be less toxic to vital tissues than non-buffered counterparts. However, buffering hypochlorite with bicarbonate renders the solution unstable with a decrease in shelf life to less than 1 week. Root Canal Irrigants, JOE — Volume 32, Number 5, May 2006

31. Finally, the caustic potential of hypochlorite solutions appears to be influenced mainly by the available chlorine rather than by pH or osmolarity . Root Canal Irrigants, JOE — Volume 32, Number 5, May 2006

32. Temperature One alternative approach to improve the effectiveness of hypochlorite irrigants in the root canal system could be to increase the temperature of low-concentration NaOCl solutions. This improves their immediate tissue-dissolution capacity. Furthermore, heated hypochlorite solutions remove organic debris from dentin shavings more efficiently than unheated counterparts. Root Canal Irrigants, JOE — Volume 32, Number 5, May 2006

33. The capacity of a 1% NaOCl at 45°C to dissolve human dental pulps was found to be equal to that of a 5.25% solution at 20°C. On the other hand, with similar short-term efficacy in the immediate environment, i.e. the root canal system, the systemic toxicity of preheated NaOCl irrigants should be lower than the one of more concentrated non heated counterparts. Root Canal Irrigants, JOE — Volume 32, Number 5, May 2006

34. Ultrasonic activation Ultrasonic activation of sodium hypochlorite has also been advocated, as this would “accelerate chemical reactions, create cavitational effects, and achieve a superior cleansing action”. hypochlorite activation has been attributed mainly to sonic (acoustic) streaming, i.e. the vortex-like fluid movement about the endosonic file. Root Canal Irrigants, JOE — Volume 32, Number 5, May 2006

35. Instruments In addition, cutting efficacy of hand instruments is improved and torsional load on rotary nickel-titanium instruments is reduced in fluid-filled environments compared to dry conditions. corrosion of instruments in prolonged contact with hypochlorite has been reported. Root Canal Irrigants, JOE — Volume 32, Number 5, May 2006

36. Submersing instruments for hours in a hypochlorite solution will induce corrosion. However, no adverse effects should be expected during the short contact periods when an instrument is manipulated in a root canal filled with hypochlorite Root Canal Irrigants, JOE — Volume 32, Number 5, May 2006

37. Regime

38. JOE — Volume 32, Number 5, May 2006 Root Canal Irrigants

39. Toxicity Mohammadi : Sodium hypochlorite in endodontics : an update review International Dental Journal (2008) Vol. 58/No.6

40. The drawbacks of NaOCl

41. CHLORHEXIDINE GLUCONATE

42. concentration Mohammadi & Abbott Chlorhexidine in endodontics 2009 International Endodontic Journal

43. Substantivity Chlorhexidine have a unique feature - dentine medicated with it acquires antimicrobial substantivity . The positively charged ions released by CHX can adsorb into dentine and prevent microbial colonization on the dentine surface for some time beyond the actual period of time of application of the medicament. Khademi et al. 2006

44. Antimicrobial substantivity depends on the number of CHX molecules available to interact with the dentine. Therefore, medicating the canal with a more concentrated CHX preparation should result in increased resistance to microbial colonization.

45. Khademi et al. found that 5 min application of 2% CHX solution induced substantivity for up to 4 weeks. Rosenthal et al. evaluated the substantivity of 2% CHX solution within the root canal system after 10 min of application and they reported that the CHX was retained in the root canal dentine in antimicrobially effective amounts for up to 12 weeks.

46. Effect of CHX on dentin

47. Antibacterial activity Basson and Tait compared the ex vivo effectiveness of calcium hydroxide, iodine potassium iodide (IKI), and CHX solution in disinfecting root canal systems that were infected with Actinomyces israelii . The root canals were exposed to either IKI, calcium hydroxide, or 2% CHX for periods of 3, 7, and 60 days. CHX was the only disinfectant that was able to eliminate A israelii .

48. Oncag et al .evaluated the antibacterial properties against Enterococcus faecalis of 5.25% NaOCl , 2% CHX, and 0.2% CHX plus 0.2% cetrimide after 5 min and 48 h. The 2% CHX and Cetrexidin ® were significantly more effective against E faecalis .

49. Two studies have investigated the antimicrobial activity against endodontic pathogens of three concentrations (0.2%, 1%, and 2%) of two forms of CHX (gel and liquid) and compared them with five concentrations of NaOCl (0.5%, 1%, 2.5%, 4%, and 5.25%). Both the 2% gel and 2% liquid formulations of CHX eliminated Staphylococcus aureus and Candida albicans within 15 sec, whereas the gel formulation killed E faecalis within 1 min . All of the tested irrigants eliminated Porphyromonas endodontalis , Porphyromonas gingivalis , and Prevotella intermedia within 15 sec.

50. CHX and Ca(OH) 2 Chlorhexidine is a cationic biguanide whose optimal antimicrobial activity is achieved within a pH range of 5.5–7.0 Therefore, it is likely that alkalinizing the pH by adding Ca(OH)2 to CHX will lead to precipitation of the CHX molecules and thereby decreases its effectiveness. Athanassiadis et al. 2007

51. . It has been demonstrated that the alkalinity of Ca(OH)2 when mixed with CHX remained unchanged. Therefore, the usefulness of mixing Ca(OH)2 with CHX still remains unclear and controversial Athanassiadis et al. 2007

52. When used as an intracanal medicament, CHX was more effective than Ca(OH)2 in eliminating E. faecalis from inside dentinal tubules. In a study by all of the CHX formulations used, including a CHX/ Ca(OH)2 50:50 mix, were efficient in eliminating E. faecalis from the dentinal tubules with a 1% CHX gel working slightly better than the other preparations. Athanassiadis et al. 2007 Almyroudi et al. (2002)

53. No tissue dissolving property Naenni et al. assessed the necrotic tissue dissolution capacity of 1% (w/v) NaOCl , 10% CHX, 3% and 30% hydrogen peroxide, 10% peracetic acid, 5% dichloroisocyanurate ( NaDCC ) and 10% citric acid. None of the test solutions except NaOCl had any substantial tissue dissolution capacity. It was concluded that this might be important when considering the use of irrigants other than NaOCl . On the whole, one of the major disadvantages of CHX is that it has no tissue solvent activity. The properties and applications of chlorhexidine in endodontics

54. ADVANTAGES

55. DISADVANTAGES

56. HYDROGEN PEROXIDE (H 2 O 2 )

57. It has antimicrobial activity against viruses, bacteria, yeasts and even fungal spores. More effective against gram positive than gram negative bacteria.

58. Mechanism of action

59. Hydrogen peroxide is an oxidizing solution and is usually used in combination with sodium hypochlorite for root canal irrigation. This results in two kinds of reactive oxygen species .

60. Root canal irrigation with NaClO and H 2 O 2 induces both biological and mechanical effects. The biological effect of NaClO and H 2 O 2 owes to tissue irritation due to the chemical reactions of O 2 - and OH - while the mechanical effect results from O 2 bubbling.

61. The final irrigation of the canal should be done with sodium hypochlorite, as hydrogen peroxide can form gas in the presence of necrotic debris and blood leading to pain. NaOCl should be used so that it can react with the remaining hydrogen peroxide and liberate the remaining oxygen, and then the canal should be dried with paper points and closed

62. IODINE COMPOUNDS

63. can penetrate into microorganisms & attacks cell molecules such as proteins, nucleotides & fatty acids, resulting in cell death. kills a wide spectrum of microorganisms found in root canals. Iodine compounds are bactericidal, fungicidal & virucidal .

64. Properties Aqueous iodine solutions are rather unstable; in solution, several iodine species are present with molecular iodine being mostly responsible for the antimicrobial activity. This was the reason for the development of Iodophors (iodine carriers): povidone iodine and poloxamer iodine. Iodophors are complexes of iodine and a solubilising agent or carrier, which acts as a reservoir of the active ‘free’ iodine.

65. Mechanism of action

66. Although germicidal activity is maintained, iodophors are considered less -active against certain fungi and spores than are tinctures (alcoholic solutions of iodine). In endodontics, Iodine potassium iodide (IKI) has been the final component of the classical tooth surface disinfection sequence, as described by Moller. Marketed as- Betadine

67. Effect on microbial flora The effectiveness of 2.5 % NaOCl and 10 % iodine has been compared by bacterial culturing and polymerase chain reaction No significant difference in the recovery of cultivable bacteria from various sites in either group was detected However bacterial DNA was detected significantly more frequently from tooth surfaces after iodine treatment than after NaOCl treatment

68. Disadvantages

69. 30% H 2 O 2 (Superoxol) – tooth surface disinfection. It acts on the organic matter on the tooth making other disinfectants like iodine , more effective. It has been widely used earlier for cleaning the pulp chamber from blood and tissue remnants

70. Chelating agent Grossman et al. 1988, Zeeck et al. 1992

71. The ability of chelators to bind and inactivate metallic ions is widely exploited in medicine. Chelators can be used to bring about excre­tion of dangerous ions in the case of metal poisoning or in the treatment of copper metabolism disturbances. Zeeck etal.1999

72. Ethylene diamine tetra acetic acid (EDTA) In 1951, the first reports on the demineralizing effect of ethylene diamine tetra acetic acid (EDTA) on dental hard tissues were published. Hahn & Reygadas , Screebny & Nikiforuk 1951

73. Ethylene diamine tetra acetic acid (EDTA) Chelators were first introduced to endodontics by Nygaard-0stby (1957), who recom­mended the use of a 15% EDTA solution (pH 7.3) with the following composition.

74. A few years later, a detergent was added in order to increase the cleaning and bactericidal potential of the EDTA solution, the new composition being known as EDTAC. EDTA in its pure form already has a lower surface tension than 1 or 5% sodium hypochlorite ( NaOCl ), saline solution or distilled water. Tasman et al. 2000 Von der Fehr & Nygaard-0stby 1963

75. Initially, chelators were used as liquids for irrigation during mechanical instrumentation of the root canal system. In 1969, Stewart et al. presented RC-Prep (pre­mier Dental; Philadelphia, PA, USA), probably the best known paste-type chelating agent.

76. Although the efficacy of liquid and paste-type EDTA preparations in softening root dentine has been a point of controversy, chelator pre­parations have been advocated frequently as adjuncts for root canal preparation, especially in narrow and calcified root canals and for removal of the smear layer. Serene 1976, Stock & Nehammer Stewart 1986, 1995, Weine 1988, Lovdahl & Gutmann 1997), ( McComb & Smith 1975, Goldman et al. 1985, Berg et al

77. Recently, paste-type chelators have gained popularity as almost all manufacturers of nickel-titanium instruments recommend their use as a lubricant during rotary root canal preparation, presumably to reduce the risk of instrument separation. Scelza et al. 2000

78. Liquid chelators Calcinase ( lege artis , Dettenhausen , Germany) is a liqiud chelator preparation and contains 17% sodium edetate , sodium hydroxide as a stabilizor and purified water. REDTA (Roth International, Chicago, IL., USA) is a17% EDTA solution with the addition of 0.84 g Cetyl -tri- methyl ammonium bromide ( Cetrimide ) to reduce sur­face tension. The other ingredients are 9.25 mL 5 M sodium hydroxide and 100 mL distilled water.

79. EDTAC and DTPAC are solutions of EDTA (15%) and diethyl- triamine - penta acetic acid (DTPA) at pH 8. When 0.75 g of the detergent Cetyl -tri-methyl ammonium bromide is added to 100 mL of these solutions, respec­tively. EDTA-T (Formula & Agao Farmacia , Sao Paulo, Brazil) consists of 17% EDTA plus sodium lauryl ether sulfate ( Tergentol ) as a detergent ( Scelza et al. 2000). Salvizol (Ravens, Konstanz, Germany) is based on a 5 % amino- quinaldinum diacetate in propylene glycol and has a pH of 6.6 (Kaufman et al. 1978).

80. EGTA (Sigma, St Louis, MO, USA) is a chelator whose main component is ethylene glycol bis (p-amino-ethyl ether)-N,N,N',N'-tetra acetic acid. It is reported to bind Ca + more specifically than EDTA ( Calt & Serper 2000). CDTA (experimental solution) is a 1% solution of cyclohexane-1,2-diaminetetraacetic acid (Cruz- Filho et al. 2001). Largal Ultra ( Septodont , Paris, France) contains a 15% EDTA solution as a disodium salt, 0.75% Cetyl -tri-methyl ammonium bromide ( Cetrimide ) and sodium hydroxide to adjust the pH value to 7.4

81. Tubulicid Plus (Dental Therapeutics, Nacka, Sweden) contains 1.5 g Amphoteric-2 (38%),0.5 benzalkonichloride , 3 g disodium EDTA dihydrate , phosphate buffer solu­tion pH 7.3 q.s ., 100 g distilled water and 50% citric acid.

82. Paste chelators Calcinase slide ( lege artis , Dettenhausen , Germany) contains 15% sodium EDTA and 58-64% water, but no peroxides, colourants or preservatives (self-preserving).

83. RC-Prep (Premier Dental, Philadelphia, PA, USA) is a combination of 10% urea peroxide, 15% EDTA and glycol in an aqueous ointment base. Oxygen is set free by the reaction of RC-Prep with a NaOCl irrigant so that pulpal remnants and blood coagulates can be easily removed from the root canal wall (Stewart et al. 1969).

84. Glyde file ( DeTrey Dentsply , Konstanz, Germany) is composed of15% EDTA and 10% ureaperoxide in aqueous solution, and its viscosity is dependent on storage condi­tions.

85. FileCare EDTA ( VDWAntaeos , Munich, Germany) also is composed of 15% EDTA and 10% urea peroxide. File-EZE ( Ultradent Products, South Jordan, UT, USA) is a chelating agent in an aqueous water-soluble solution containing 19% EDTA.

86. Mechanism of action They function by forming calcium chelate solution with calcium ions of dentine. The dentine thereby becomes more friable and easier to instrument. Their action is to substitute sodium ions which combine with the dentine to give soluble salts, for calcium ions that are bound in less soluble combination. The walls of canal are thus softer and canal enlargement is facilitated.

87. REVIEW : Chelating agents in root canal treatment: mode of action and indications for their use.International Endodontic Journal , 36, 810-830, 2003.

88. Effect on microbial flora EDTA has limited antibacterial effects. On direct exposure for extended time EDTA extracts bacterial surface proteins by combining with metal ions from the cell envelope, which can eventually lead to bacterial death. This is thought to be because of chelation of cations from the outer membranes of bacteria. Antibacterial properties of EDTA depend on concentration and pH.

89. By combining NaOCl with EDTA, bactericidal effect was enhanced because of smear layer removal by EDTA . Bystrom and Sundquist 1992

90. Effect on smear layer EDTA removes smear layer on dentine resulting in better surface contact between canal filling and dentinal wall and better penetration of sealer into dentinal tubules.

91. Smear layer is not removed completely by 5.25% NaOCl irrigation alone but is removed by combined use with EDTA. Electron microscopy has shown that the smear layer contains both organic and inorganic substances It appears, however, to consist mostly of inorganic compo­nents as root canal irrigation with NaOCl has little effect on removal of this layer. Yamada et al. 1983, Pashley 1984, Kogkapan 1987

92. Partial if not complete smear layer removal is achieved only with the aid of acids and chelators Numerous studies have reported that irrigation with a 17% EDTA solution has a good cleaning effect on the root canal walls . Yamada et al. 1983, Kogkapan 1987 Pashley 1992

93. Pawlicka et al. reported that the root canal wall is clean along its entire length after use of EDTA preparations, other authors found that the cleaning action is reduced towards the apex and therefore more efficient in the coronal- and middle-third of the root. The number of visible tubule openings reduces from coronal to apical.

94. Working time of chelators Still, the optimal working time of chelating agents is unknown. A certain cleaning effect is achieved after che­lator application for a few minutes. According to Gold­berg the optimal cleaning effect is only achieved after 15 min

95. Several studies have reported a good cleaning effi­cacy of liqiud or paste-type EDTA after working times between 1 and 5 min. Hulsmann & Heckendorff 2002, Scelza et al. 2003

96. 1-min exposure to 10 mL EDTA was sufficient to remove the smear layer, whereas an exposure for 10 min caused excessive peritubular and intratubular erosion. This kind of erosion has been proposed because of the result of the combined use of EDTA and NaOCl rather than EDTA alone. Calt & Serper 2002 Niu et al. 2002.

97. Effect of EDTA on the quality of root canal obturation An increased number of obturated accessory canals is found after final irrigation with NaOCl (6%) alone or in combination with EDTA than after no irrigation or irriga­tion with distilled water Villegas et al. 2002

98. On the other hand, both NaOCl and RC-Prep significantly reduced the bond strength of resin cement to root den­tine This reduction can be completely reversed by application of 10% ascorbic acid or 10% sodium ascorbate . Dental adhesives bound significantly better to calcified dentine than to decalcified dentine pre- treated with EDTA Morris et al. 2001 Perdigao et al. 2001

99. Recommendation