|
 
 |
| ORIGINAL ARTICLES |
|
| Year : 2015 | Volume
: 2
| Issue : 3 | Page : 117-119 |
|
Efficacy of MTAD with shortened irrigation time on smear layer removal after rotary canal instrumentation: An in vitro study
Vaishak Kustagi1, PR Shaktidar2, NK Prabhakar3
1 Department of Conservative Dentistry and Endodontics, Sharavathi Dental College, Karnataka, India
2 Department of Conservative Dentistry and Endodontics, Subbaiah Institute of Dental Sciences, Shimoga, Karnataka, India
3 Department of Conservative Dentistry and Endodontics, K.V.G. Dental College, Karnataka, India
| Date of Web Publication | 19-Nov-2015 |
Correspondence Address:
Vaishak Kustagi
Department of Conservative Dentistry and Endodontics, Sharavathi Dental College, Karnataka
India
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/2348-2915.169824
Context: A search in the endodontic literature showed the absence of any reports regarding the use of a mixture of tetracycline, acid, and detergent (MTAD) to remove smear layer at shortened irrigation time. Aims: To determine the efficacy of MTAD with shortened irrigation time on smear layer removal after Pro Taper rotary canal instrumentation. Methods: Twenty single-rooted lower premolar teeth were randomly divided into two experimental groups. After decoronation of all the samples, working length was determined and all the teeth were instrumented to master apical size # 30 (F3), using Pro Taper rotary files. Teeth were irrigated with 3% NaOCl during instrumentation. Experimental groups one and two were irrigated with a 5 ml final rinse using MTAD for 5 min and 2.5 min, respectively. After irrigation, all root canals were dried with absorbent paper points. The teeth were then sectioned longitudinally and prepared for a scanning electron microscopic examination. The scanning electron microscope photographs were evaluated using a standard scoring system developed by Rome et al. Statistical Analysis Used: Results were statistically analyzed using Mann–Whitney U-test. Results: When intercomparison was made between Group 1 and 2 at the coronal and middle third, statistically significant difference was observed, with Group 1 having significantly less smear layer than Group 2. In apical third, no statistically significant difference was observed between Group 1 and 2, even though smear layer removal was more in Group 1 than Group 2. Conclusion: Effective smear layer removal was not possible with shortened irrigation time using MTAD. Keywords: MTAD, SEM study, smear layer removal
How to cite this article:
Kustagi V, Shaktidar P R, Prabhakar N K. Efficacy of MTAD with shortened irrigation time on smear layer removal after rotary canal instrumentation: An in vitro study. J Dent Res Rev 2015;2:117-9 |
How to cite this URL:
Kustagi V, Shaktidar P R, Prabhakar N K. Efficacy of MTAD with shortened irrigation time on smear layer removal after rotary canal instrumentation: An in vitro study. J Dent Res Rev [serial online] 2015 [cited 2022 Jun 28];2:117-9. Available from: https://www.jdrr.org/text.asp?2015/2/3/117/169824 |
| Introduction | |  |
The success of root canal treatment depends on the debridement of diseased tissue, elimination of bacteria present in the canals including dentinal tubules and prevention of reinfection after treatment. This is accomplished by thoroughly cleaning, shaping, and disinfecting the root canal system followed by a three-dimensional obturation.[1]
Studies have shown that smear layer covers on the instrumented root canal walls after cleaning and shaping.[2]
During instrumentation of root canals walls, dentin chips are created by the action of endodontic instruments. Smear layer consists of organic and inorganic matter and can form two zones. The first zone is on the canal wall surface and is 1-2 µm thick. The second zone extends into dentinal tubules to a depth of about 40 µm.[3]
Time required to achieve the disinfecting effect of various intracanal medications is reduced by the removal of smear layer.[4] The presence of smear layer can inhibit or significantly reduce the penetration of intracanal medicaments and irrigants into the dentinal tubules.[5] It has been substantiated that better adhesion of obturating materials to the canal walls occurs in the absence of the smear layer.[6] Recent systematic review and meta-analysis of leakage studies concluded that the absence of smear layer improves the fluid tight seal of the canal walls.[7]
There are various methods to eliminate smear layer in clinical practice, which include chemical, mechanical, and by means of laser. Irrigation of root canal system is one of the chemical means to remove the smear layer and also a critical adjunct in debridement. Irrigation acts as a physical flush to remove debris and should also act as bactericidal agent, tissue solvent, and lubricant.
A mixture of tetracycline, citric acid, and tween 80 detergent (MTAD) is an irrigant used for the removal of smear layer. Structure of the dentinal tubules is not significantly changed when canals are irrigated with NaOCl and followed with a final rinse of MTAD for 5 min.[8]
A search in the endodontic literature showed the absence of any reports regarding the use of MTAD to remove smear layer at shortened irrigation time. The purpose of this in vitro study on extracted tooth is to determine the efficacy of MTAD with shortened irrigation time on smear layer removal after Pro Taper rotary canal instrumentation.
| Methods | | |
Twenty single-rooted lower premolar human teeth extracted for periodontal reasons were used in this study.
The crowns of all 20 mandibular premolar teeth were severed at the proximal cemento-enamel junction. The canal patency was determined by passing no. 10 k-file into the canal until the end of the file was seen at the apical foramen. The teeth were randomly divided into two experimental groups, each group consisting of 10 teeth. The working lengths was established by placing #10 file into the root canal until it was visible at the apical foramen, then 1 mm was subtracted from that length. The root canals were instrumented in a crown-down technique using Pro Taper rotary files (Dentsply, Maillefer, Switzerland) to master apical size # 30 (F3), irrigating with 1 ml of 3% NaOCl.
Experimental Groups 1 and 2 were irrigated with a 5 ml final rinse using MTAD for 5 min and 2.5 min, respectively. After irrigation, all root canals were dried with absorbent paper points.
The teeth were slit vertically along the long axis. To ensure that the slitting process did not damage the inside of the canal, water-cooled diamond disc was used to section along the root, thereby creating a straight canal. Teeth were then split using a chisel.
One half of each tooth was selected randomly and placed in a 2% glutaraldehyde solution for 12 h. Specimens were dehydrated using graded concentration of ethanol starting from 30% and then 50%, 70%, 90%, and 100%. The specimens were fixed on an aluminum stub for gold ion sputtering and viewed under scanning electron microscope (SEM) at 10 kV accelerating voltage. After a general survey of the entire canal wall, photomicrographs were taken at ×1000 magnification of the representative area of the coronal, middle, and apical third of canal. The photomicrographs of the cervical third, middle third, and apical third were taken and compared. The SEM photographs were evaluated using a scoring system developed by Rome et al. (1985).
- 0 = Smear layer not seen, dentinal tubules open, free of debris
- 1 = Moderate smear layer, outlines of dentinal tubules visible or partially filled with debris
- 2 = Heavy smear layer, outlines of dentinal tubules obliterated.
The results were statistically analyzed using Mann–Whitney U-test.
| Results | | |
SEM images of various regions of canals are shown in [Figure 1]. When comparing the smear layer removal in the cervical third, 90% of specimens in Group 1 were free of smear layer and 10% with few areas covered with smear layer [Figure 1]a. In Group 2, 40% of the specimens were free of smear layer and 60% with few areas covered by smear layer [Figure 1]d. None of the samples had all or most of the area covered by smear layer. When comparison was made between Group 1 and 2 at the coronal third [Table 1], statistically significant difference (P < 0.05) was observed, with Group 1 having significantly less smear layer than Group 2. | Figure 1: (a) coronal third of specimen irrigated with mixture of tetracycline, acid, and detergent for 5 min (b) middle third of specimen irrigated with mixture of tetracycline, acid, and detergent for 5 min
(c) apical third of specimen irrigated with mixture of tetracycline, acid, and detergent for 5 min (d) coronal third of specimen irrigated with mixture of tetracycline, acid, and detergent for 2. 5 min (e) middle third of specimen irrigated with mixture of tetracycline, acid, and detergent for 2. 5 min (f) apical third of specimen irrigated with mixture of tetracycline, acid, and detergent for 2.5 min
Click here to view |
The smear layer removal at the middle third, 80% of the specimen in Group 1 was free of smear layer, 20% with few areas covered by smear layer [Figure 1]b. In Group 2, 30% of the specimens were free of smear layer and 70% with few areas covered by smear layer [Figure 1]e. Comparison at the middle third showed that Group 1 having significantly less smear layer than Group 2 [Table 1].
In apical third, 20% of the specimen in Group 1 was free of smear layer and 80% with few areas covered with smear layer [Figure 1]c. In Group 2, 90% of the specimens had few areas covered by smear layer and 10% with all the area covered by smear layer [Figure 1]f. No statistically significant difference (P < 0.05) was observed between the two groups, even though smear layer removal was more in Group 1 than in Group 2 [Table 1].
| Discussion | | |
Root canal system presents a unique site where soft and hard tissue of infected tooth needs to be debrided and rendered bacteria free prior to the obturation of the canals. The objectives of root canal treatment are the removal of bacteria present in the canals and dentinal tubules, and prevention of reinfection after treatment. These objectives are accomplished by thoroughly cleaning, shaping, and disinfecting the root canal system. Although primary method for canal debridement is instrumentation, irrigation acts as a critical adjunct. Irrigation serves as a physical flush to remove debris as well as serving as a bactericidal agent, tissue solvent, and lubricant for instrumentation. Furthermore, some irrigants are effective in removing the smear layer.[9]
MTAD is an effective solution for the removal of smear layer and does not significantly change the structure of the dentinal tubules when canals are irrigated with NaOCl and followed with a final rinse of MTAD for 5 min.[8] The present study was aimed to evaluate the efficacy of MTAD with shortened irrigation time on smear layer removal.
Based on the results of the present study, it can be concluded that optimal regimen for effectively removing the smear layer in root canals is a 5 ml of final rinse using MTAD for 5 min.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
| References | | |
| 1. | Moodnik RM, Dorn SO, Feldman MJ, Levey M, Borden BG. Efficacy of biomechanical instrumentation: A scanning electron microscopic study. J Endod 1976;2:261-6.  [ PUBMED] |
| 2. | McComb D, Smith DC. A preliminary scanning electron microscopic study of root canals after endodontic procedures. J Endod 1975;1:238-42. [ PUBMED] |
| 3. | Teixeira CS, Felippe MC, Felippe WT. The effect of application time of EDTA and NaOCl on intracanal smear layer removal: An SEM analysis. Int Endod J 2005;38:285-90. |
| 4. | Ørstavik D, Haapasalo M. Disinfection by endodontic irrigants and dressings of experimentally infected dentinal tubules. Dent Traumatol 1990;6:142-9. |
| 5. | Bystrom A, Sundqvist G. The antibacterial action of sodium hypochlorite and EDTA in 60 cases of endodontic therapy. Int Endod J 1985;18:35-40. [ PUBMED] |
| 6. | Abramovich A, Goldberg F. The relationship of the root canal sealer to the dentine wall. An in vitro study using the scanning electron microscope. J Br Endod Soc 1976;9:81-6. [ PUBMED] |
| 7. | Shahravan A, Haghdoost AA, Adl A, Rahimi H, Shadifar F. Effect of smear layer on sealing ability of canal obturation: A systematic review and meta-analysis. J Endod 2007;33:96-100. |
| 8. | Torabinejad M, Khademi AA, Babagoli J, Cho Y, Johnson WB, Bozhilov K, et al. A new solution for the removal of the smear layer. J Endod 2003;29:170-5. |
| 9. | Harrison JW. Irrigation of the root canal system. Dent Clin North Am 1984;28:797-808. [ PUBMED] |
[Figure 1]
[Table 1]
|
Search Pubmed for