J Interdiscip Dentistry
Home | About JID | Editors | Search | Ahead of print | Current Issue | Archives | Instructions |
Home Print this page Email this page Small font sizeDefault font sizeIncrease font size
Users Online: 253  | Login  | Contact us | Advertise | Subscribe  


 
Table of Contents
ORIGINAL ARTICLE
Year : 2014  |  Volume : 4  |  Issue : 3  |  Page : 130-134

An evaluation of horizontal depth of penetration of various irrigants into the dentinal tubules when used alone and in combination with diode laser: An in vitro study


1 Department of Conservative Dentistry and Endodontics, Manipal College of Dental Sciences, Mangalore, Manipal University, Karnataka, India
2 Department of Microbiology, Kasturba Medical College, Manipal University, Mangalore, Karnataka, India
3 Department of Conservative Dentistry and Endodontics, M. A. Rangoonwala Dental College and Research Centre, Pune, Maharashtra, India

Date of Web Publication18-Dec-2014

Correspondence Address:
M Kundabala
Department of Conservative Dentistry and Endodontics, Manipal College of Dental Sciences, Mangalore, Manipal University, Karnataka
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/2229-5194.147331

Rights and Permissions
   Abstract 

Aim: The purpose of this study is to evaluate the horizontal depth of prenetration of various irrigants into dentinal tubules using sodium hypochlorite, chlorhexidine and diode laser when used alone and in combination. Materials and Methods: 60 single rooted extracted human teeth were collected. Access cavity was prepared and the canals enlarged to file size 30 of 0.04 taper rotary instrument. After decoronation, vertical grooves extending from coronal to apical thirds were done on proximal surfaces of each tooth roots. Following which EDTA was used to remove the smear laryer from the root canal dentin and a turbid suspension of Enterococcus faecalis was inoculated in the root canals and incubated at 370C for 24 hours. The teeth were divided into 4 groups of 15 teeth each: Group Group I positive control, Group II diode laser irradiation, Group III 2.5% sodium hypochlorite and 0.2% chlorhexidine gluconate, Group IV 2.5% sodium hypochlorite and 0.2% chlorhexidine gluconate and diode laser irradiation. Irrigation of each group followed by the splitting the tooth into two halves were done within a lumina air flow chamber using chisel and a mallet. Prepared teeth samples from each group were then subjected to environmental scanning electron microscopy to the horizontal depth of penetration of various irrigation into dentinal tubules. Results: The horizontal depth of penetration of various irrigants were calculated in each group and statistical analysis done using Kruskal Wallis test for group comparison. The group where irrigation was done with 2.5% NaOCl, 0.2% chlorhexidine gluconate and irradiation with high power diode laser performed against Enterococcus faecalis showed the best results when compared with other groups. Conclusion: The horizontal depth of penetration was more when 2.5% NaOCl, 0.2% chlorhexidine gluconate in combination with 810nm diode laser was used.Hence this combination can be used for effective disinfection of the root canal system during chemomechanical preparation.
Clinical Relevance To Interdisciplinary Dentistry

  • Combination of NaOCl ,Chlorhexidine gluconate and Laser can be used for effective disinfection of the root canal system during chemomechanical preparation before we give a final restoration
  • Prognosis of the root canal therapy will be better with prevention of reinfection with this combination of irrigant
  • Prolonged action of this combination of irrigants with laser which penetrate deep into radicular dentinal tubules will maintain the sterility of root canal system.

Keywords: Chlorhexidine, diode laser irradiation, environmental scanning electron microscopy, NaOCl


How to cite this article:
Rajeshwari, Kamath P, Kundabala M, Shenoy S, Hegde V, Thukral N. An evaluation of horizontal depth of penetration of various irrigants into the dentinal tubules when used alone and in combination with diode laser: An in vitro study . J Interdiscip Dentistry 2014;4:130-4

How to cite this URL:
Rajeshwari, Kamath P, Kundabala M, Shenoy S, Hegde V, Thukral N. An evaluation of horizontal depth of penetration of various irrigants into the dentinal tubules when used alone and in combination with diode laser: An in vitro study . J Interdiscip Dentistry [serial online] 2014 [cited 2019 Jul 16];4:130-4. Available from: http://www.jidonline.com/text.asp?2014/4/3/130/147331


   Introduction Top


Sterilization of the root canal system, in its purest form, is all but impossible, as bacteria can remain after root canal cleaning and shaping. If the original cause of the diseases is admitted to be irritation from decomposing pulp, its removal will in most cases effect a cure. [1] Once bacterial invasion of pulp tissue has taken place, the root canal system becomes a "privileged sanctuary" for clusters of bacteria, bacterial by-products and degradation products of both microorganisms and pulpal tissue. [2]

Chemo mechanical preparation of root canal system results in total disruption of microbial ecosystem. Failed root canal treatments have been attributed to viable bacteria that exist within the root canal, periapical system and dentinal tubules can be a source of reinfection or continued periapical inflammation. [3],[4]

An endodontic irrigant should ideally exhibit powerful antimicrobial activity, dissolve organic tissue remnants, disinfect the root canal space, flush out debris from instrumented root canals, provide lubrication, and have no cytotoxic effects on the periradicular tissues among other properties. [5],[6] Effectiveness of an endodontic irrigating solution is dependent on the penetration of irrigant and duration of action against a bacteria often is associated with endodontic failure. Although an irrigant can penetrate far into the tubules, the concentration may not be sufficient to kill all types of bacteria present. Antibacterial activity may be reduced as reactions involving tissue dissolution and death of bacteria occur. Therefore, the effectiveness of an irrigating solution, particularly at distal ends of tubules may be reduced.

Report  by Sundqvist et al.(1998) concluded that Enterococcus faecalis is the most commonly recovered species form obturated root canals that have the ability to survive as a single organism without the support of other bacteria. [3] It has been postulated that a virulence factor of E. faecalis may be related to its ability to invade dentinal tubules and adhere to collagen in the presence of human serum. Recognizing the potential role of E. faecalis in the failure of root canal therapy makes it important to develop strategies to control infections caused by this organism. [7] Bystrφm and Sundqvist demonstrated mechanical instrumentation reduced bacteria by only 50%; in order to predictably eliminate bacteria in total or near total debridement at all levels - pulpal, midpulpal and cemental region of root canals in horizontal plane, action of a disinfecting agent is mandatory. [7],[8]

Most commonly used effective irrigant is sodium hypochlorite that is essential for the sanitization process because it favors cleaning and shaping and dissolves the necrotic content. However, it is known to produce allergic reactions and cause emphysema if accidentally extruded periapically. [9] Therefore, an equally effective, but safer irrigant is desirable.

Chlorhexidine (CHX) gluconate is a wide spectrum antimicrobial agent, unique in its ability to bind oral tissues for extended periods, from which it is released slowly (substantivity), and it is relatively nontoxic. [10] An in vitro study by Kuruvilla and Kamath concluded that when NaOCl and CHX solutions were combined within the root canal, the antibacterial action was suggestive of being augmented. [11] Gutiιrrez et al. showed that the root canal system is complex, and its ramifications are consistently untouched by the usual instrumentation, harboring areas that are never contacted by an endodontic instrument. [12]

Gutknecht et al. analyzed the effects of the high power diode laser on extracted human teeth experimentally infected with E. faecalis. They reported that the average decrease of 99.91% of bacteria occurred after irradiation. [13]

The purpose of this study is to determine the antimicrobial efficacy of high power diode laser alone and in combination with alternate combined use of 2.5% NaOCl and 0.2% CHX gluconate against E. faecalis using saline as a control, at pulpal, mid pulpal and cemental region of the root canals, in horizontal plane.

Objectives of this study, to evaluate the efficacy of:

  • 2.5% NaOCl, 0.2% CHX gluconate as root canal irrigants
  • Diode laser irradiation
  • combinations of 2.5% NaOCl and 0.2% CHX gluconate as irrigants followed by diode laser irradiation in eradicating E. faecalis, by evaluating the depth of penetration of irrigating solutions into dentinal tubules.



   Materials and methods Top


The study is performed in the Department of Conservative Dentistry and Endodontics, 60 single-rooted extracted human teeth with type I canal anatomy were received from Department of Oral and Maxillofacial Surgery. Access cavity was prepared. Root canals are prepared using Protaper Rotary Instruments to enlarge the canals till file size F3 according to manufacturers' instructions. Canals were irrigated with 2.5% NaOCl and with 0.2% CHX. Postirrigation with NaOCl, canals were thoroughly flushed with saline and dried with absorbent points to prevent any formation of precipitation before the final irrigation with CHX. Decoronation was done with the help of diamond discs. Vertical grooves extending from coronal to apical thirds were done on the proximal surfaces of each tooth roots. Canals were then treated with 17% ethylenediaminetetraacetic acid (EDTA) for 1 min to remove the smear layer and teeth were sterilized by autoclaving, after wrapping them within cotton rolls.

A turbid suspension of E. faecalis was obtained by growing the cells in brain heart infusion broth (The Media Laboratories Pvt. Ltd, India) for 6 h at 37°C. The bacteria laden suspension is placed into the canal using a sterile 27 gauge syringe and incubated at 37°C for 24 h.

The teeth are then divided into four groups of 15 teeth each:

  • Group I - Positive control groups, canals are flushed with 0.9% saline (Parenteral drugs, India Pvt. Ltd) for 1 min
  • Group II - A diode laser of 24 W, 15 Hz frequency, wavelength of 810 nm is used for this study (Opus IO Dental Diode Laser System [OpusDent Ltd.]) The optical fiber is introduced and activated and slowly applied from coronal to apical ends of the root canal under continuous circling movements to irradiate all dentinal tubules. This is done 3 times for a period of 5 s in contact mode
  • Group III - The irrigant action was tested in the following manner. 2.5% freshly prepared sodium hypochlorite (Novodent Equipments and Materials Ltd., Mumbai, India) was injected passively into the canal using a sterile 27 gauge syringe for 30 s, followed by 0.2% freshly prepared CHX gluconate (Manipal Pharmaceuticals, Manipal, India) injected passively into the canal for 30 s.


In Group IV, a combination of the above two groups was done i.e. 2.5% freshly prepared sodium hypochlorite injected passively into the canal for 30 s, 2% freshly prepared CHX gluconate was passively injected into the canal for 30 s followed by a diode lasing (specification same as in Group II).

Irrigation of each group, followed by splitting the tooth into two halves was done within a lumina air flow chamber using chisel and a mallet. Prepared teeth sample from each group were then subjected to  environmental scanning electron microscopy (ESEM) which gives a magnification range of 5,000× with voltage of 200 V to 30 KV. The depth of penetration of various irrigants and the diode laser alone and in combination with an alternate use of 2.5% sodium hypochlorite and 2% CHX gluconate against E. faecalis using saline as a control was measured [Figure 1].
Figure 1: (a) ESEM view of radicular dentin irrigated with saline (Control group). (b) ESEM view of radicular dentin iradiated with Diode laser (Group-II). (c) ESEM view of radicular dentin irrigated with NaOCl+CHX (Group-III). (d) ESEM view of radicular dentin irrigated with combination of NaOCl+CHX and Diode laser (Group-IV)

Click here to view


RESULTS AND STATISTICAL ANALYSIS

Results of this study are given in [Table 1].
Table 1: Mean values and standard deviation of depth of penetration of irrigants


Click here to view


Group IV (2.5% NaOCl + 0.2% CHX + diode laser) showed maximum horizontal depth of penetration with mean value of 21.207 μm. with standard deviation (SD) 6.29615. and saline showed least value of 2.8230 μm with SD 32703. Kruskal-Wallis test was used to compare the data obtained under each group for statistical analysis [Graph 1].




   Discussion Top


The success of root canal treatment is dependent on mechanical preparation, irrigation, microbial control and complete obturation of the root canal. The flushing action of the irrigation solution aids the removal of debris and organic material from the root canal, as well as helping to lubricate endodontic instruments. Properties such as antimicrobail activity, tissue dissolving ability, and nontoxicity to the periapical tissues are important requirements of an endodontic irrigant. [14]

A major objective in endodontic therapy is to disinfect the root canal system before obturation of the canal system. Sodium hypochlorite is the current irrigant of choice for disinfection and CHX gluconate is an effective oral antimicrobial agent with a broad - spectrum of activity substantivity, and relative absence of toxicity. [9] Study has shown the use of sodium hypochlorite and CHX gluconate resulted in the greatest percentage reduction of postirrigant positive culture. This reduction was significant when compared with use of sodium hypochlorite alone, but not significant when compared with use of only CHX gluconate. [11]

In an earlier in vitro study Moritz et al. analyzed the effects of a high power diode laser on extracted human teeth experimentally infected with E. faecalis. They reported that the average decrease in microorganisms was 99.91%, which occurred when laser irradiation was done. The relatively long duration of irradiation and appropriate guidance of light conductor fiber in conjunction with the enlargement of beam diameter in short distance from the outlet guarantees sufficient treatment of the root canal wall and irradiation of all bacteria. [15]

Bystorm have shown that failure of endodontic treatment of nonvital teeth is due to the presence of persistent bacteria in the root canal, root dentin and cementum. [16] The fact that the highly virulent E. faecalis has a role in chronic endodontic treatment failure because of their resistance to intracanal medicaments and their ability to survive in the root canal without the support of other bacteria have made to choose the microorganism for the study. Moreover, their cells maintain the capacity to invade the dentrial tubules and adhere to collagen in the presence of human serum. [17]

In the present study, Group IV, where the root canals are irrigated with 2.5% sodium hypochlorite, 2% CHX gluconate and irradiated with a high power diode laser showed the best results when compared with Group II-diode laser irradiation alone and Group III-irrigation with alternate combined use of 2.5% of sodium hypochlorite and 2% CHX as well as the control group only saline irrigation [Graph 1]. Results of the present study are similar to the results obtained by Kuruvilla and Kamath, which suggest that when these solutions are combined in the root canal, the antibacterial action is being augmented. The reasons could be following:

  • Chlorhexidine is a base, itself capable of forming salts with a number of organic acids
  • Sodium hypoclorite is an oxidizing agent that may be capable of oxidizing the gluconate part of the CHX gluconate to gluconic acid. The chlorogroup might be added onto the guanidine component of the CHX molecule, thereby forming "CHX chloride". This increases the ionizing capacity of the CHX molecule. [11]


In the present study, intergroup comparison of horizontal penetration of various irrigants by Mann-Whitney test showed that the value was "highly significant" when combination of NaOCl + CHX + laser (Group IV) compared with positive control (Group I), laser alone (Group II) and NaOCl + CHX (Group III). Group III is showing significantly better results than Group I. Group 2 and3 showing no statistical difference among them [Table 2].
Table 2: Showing inter group comparison of horizontal penetration of various irrigants by Mann Whitney test


Click here to view


Takeda et al. evaluated the removal of smear layer by three endodontic irrigants and two types of laser, and suggested that CO2 and Er:YAG lasers were more efficient in removing the smear layer than EDTA and the acidic solutions. [18] The present study did not evaluate the smear layer removal capacity of diode laser. Further studies are needed to evaluate the smear layer removal capacity of diode laser. Mckintey and Ludlow evaluated the potential of spreading bacterial contaminants from the root canal to the patient and dental team via the smoke produced by the laser. In the smoke plume of the argon laser, viable bacteria have been found. [19] Moritz et al. irradiated the infected root canals with diode laser, and they were able to eliminate 99.91% infected E. faecalis bacteria on average. [15] A maximum of two irradiations resulted in nearly complete elimination of bacteria. Further studies should be done to confirm the results obtained in the present study, by increasing the number of samples.

The advantage to using ESEM in the present study is operating it in "wet mode" as it is not necessary to make nonconductive samples conductive. Material samples do not need to be desiccated and coated with gold or palladium and thus their original characteristics may be preserved for further testing or manipulation. In conventional scanning electron microscopy a relatively high vacuum in the specimen chamber is needed to prevent atmospheric interference with primary or secondary electrons, whereas an ESEM may be operated with a poor vacuum (up to 10 Torr of vapor pressure or one seventy-sixth of an atmosphere) in the specimen chamber. In such "wet mode" imaging the specimen chamber is isolated from the rest of the vacuum system. Water is the most common imaging gas and a separate vacuum pump permits free control of its vapor pressure in the specimen chamber. [20]


   Conclusion Top


The present study concluded that:

  • Combination of 2.5% NaOCl, 2% CHX gluconate with Diode laser is very effective in eliminating E. faecalis with good horizontal depth of penetration of irrigants into the dentinal tubules
  • 810 nm diode laser can be used as an effective adjuvant to chemomechanical irrigation of the root canal system
  • ESEM is an excellent tool for studying the ultra-structural morphology of dentin.


 
   References Top

1.
Gutmann JL. Clinical, radiographic, and histologic perspectives on success and failure in endodontics. Dent Clin North Am 1992;36:379-92.  Back to cited text no. 1
    
2.
Möller AJ, Fabricius L, Dahlén G, Ohman AE, Heyden G. Influence on periapical tissues of indigenous oral bacteria and necrotic pulp tissue in monkeys. Scand J Dent Res 1981;89:475-84.  Back to cited text no. 2
    
3.
Sundqvist G, Figdor D, Persson S, Sjögren U. Microbiologic analysis of teeth with failed endodontic treatment and the outcome of conservative re-treatment. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1998;85:86-93.  Back to cited text no. 3
    
4.
Safavi KE, Spangberg LS, Langeland K. Root canal dentinal tubule disinfection. J Endod 1990;16:207-10.  Back to cited text no. 4
    
5.
Harrison JW. Irrigation of the root canal system. Dent Clin North Am 1984;28:797-808.  Back to cited text no. 5
[PUBMED]    
6.
Nair PN. Apical periodontitis: A dynamic encounter between root canal infection and host response. Periodontol 2000 1997;13:121-48.  Back to cited text no. 6
    
7.
Byström A, Sundqvist G. Bacteriologic evaluation of the effect of 0.5 percent sodium hypochlorite in endodontic therapy. Oral Surg Oral Med Oral Pathol 1983;55:307-12.  Back to cited text no. 7
    
8.
Berutti E, Marini R, Angeretti A. Penetration ability of different irrigants into dentinal tubules. J Endod 1997;23:725-7.  Back to cited text no. 8
    
9.
Jeansonne MJ, White RR. A comparison of 2.0% chlorhexidine gluconate and 5.25% sodium hypochlorite as antimicrobial endodontic irrigants. J Endod 1994;20:276-8.  Back to cited text no. 9
    
10.
Ringel AM, Patterson SS, Newton CW, Miller CH, Mulhern JM. In vivo evaluation of chlorhexidine gluconate solution and sodium hypochlorite solution as root canal irrigants. J Endod 1982;8:200-4.  Back to cited text no. 10
    
11.
Kuruvilla JR, Kamath MP. Antimicrobial activity of 2.5% sodium hypochlorite and 0.2% chlorhexidine gluconate separately and combined, as endodontic irrigants. J Endod 1998;24:472-6.  Back to cited text no. 11
    
12.
Gutiérrez JH, Jofré A, Villena F. Scanning electron microscope study on the action of endodontic irrigants on bacteria invading the dentinal tubules. Oral Surg Oral Med Oral Pathol 1990;69:491-501.  Back to cited text no. 12
    
13.
Gutknecht N, Moritz A, Conrads G, Lampert G. Der dioder laser and seine bacterioizide wirking in wurzerkanal eine in vitro studie. Endodontie 1997;3:217-22. Cited from J Oral Laser Appl 2002;2:151-7.  Back to cited text no. 13
    
14.
Grossman LI. Irrigation of root canals. J Am Dent Assoc 1943;30:1915. As cited from Dent Clin North Am 1970;14:743-52.  Back to cited text no. 14
    
15.
Moritz A, Gutknecht N, Goharkhay K, Schoop U, Wernisch J, Sperr W. In vitro irradiation of infected root canals with a diode laser: Results of microbiologic, infrared spectrometric, and stain penetration examinations. Quintessence Int 1997;28:205-9.  Back to cited text no. 15
    
16.
Bystorm. Evaluation of endodontic treatment of teeth with apical periodontitis (dissertation). Vol. 27. Umea, Sweden: Umea University Odontalogical Dissertations; 1986. p. 20-4. As cited from Endod Dent Traumatol 1997;13:139-45.  Back to cited text no. 16
    
17.
Buck RA, Eleazer PD, Staat RH, Scheetz JP. Effectiveness of three endodontic irrigants at various tubular depths in human dentin. J Endod 2001;27:206-8.  Back to cited text no. 17
    
18.
Takeda FH, Harashima T, Kimura Y, Matsumoto K. A comparative study of the removal of smear layer by three endodontic irrigants and two types of laser. Int Endod J 1999;32:32-9.  Back to cited text no. 18
    
19.
McKinley IB Jr, Ludlow MO. Hazards of laser smoke during endodontic therapy. J Endod 1994;20:558-9.  Back to cited text no. 19
    
20.
McDonald AM. Environmental scanning electron microscopy. Mater World 1998;6:399-401.  Back to cited text no. 20
    


    Figures

  [Figure 1]
 
 
    Tables

  [Table 1], [Table 2]


This article has been cited by
1 Effect of Different Agitation Techniques on the Penetration of Irrigant and Sealer into Dentinal Tubules
Yu Gu,Hiran Perinpanayagam,David J.W. Kum,Yeon-Jee Yoo,Jin-Sun Jeong,Sang-Min Lim,Seok-Woo Chang,Seung-Ho Baek,Qiang Zhu,Kee-Yeon Kum
Photomedicine and Laser Surgery. 2016;
[Pubmed] | [DOI]



 

Top
 
  Search
 
    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Access Statistics
    Email Alert *
    Add to My List *
* Registration required (free)  

 
  In this article
    Abstract
   Introduction
    Materials and me...
   Discussion
   Conclusion
    References
    Article Figures
    Article Tables

 Article Access Statistics
    Viewed2501    
    Printed36    
    Emailed0    
    PDF Downloaded558    
    Comments [Add]    
    Cited by others 1    

Recommend this journal