|Year : 2021 | Volume
| Issue : 3 | Page : 149-152
Spectrophotometric analysis of crown discoloration induced by various intracanal medicaments: An in vitro study
Amishi Amit Parikh, DN Nirupama, DN Naveen, J Sindhu, Mohan Thomas Nainan
Department of Conservative Dentistry and Endodontics, Vydehi Institute of Dental Sciences and Research Centre, Bengaluru, Karnataka, India
|Date of Submission||11-Jun-2021|
|Date of Decision||01-Jul-2021|
|Date of Acceptance||04-Sep-2021|
|Date of Web Publication||30-Sep-2021|
Dr. Amishi Amit Parikh
Rajiv Gandhi University of Health Sciences, Bengaluru, Karnataka
Source of Support: None, Conflict of Interest: None
Aim: The aim of the study was to assess discoloration potential of four different intracanal medicaments.
Materials and Methods: Thirty single-rooted extracted bovine incisors were sectioned to a standardized root length, accessed, instrumented, and placed with temporary filling and cotton pellet. The specimens were divided into five groups (n = 6): Control group with no intracanal medicament and four groups with the following medicaments, i.e., calcium hydroxide (Ca(OH)2), calcium hydroxide with chlorhexidine (Ca(OH)2 with CHX), triple antibiotic paste (TAP), and silver diamine fluoride (SDF), respectively. Calorimetric evaluation, according to CIE L*a*b* system, was performed at pretreatment, on day 1, 7, 14, and 21. Data were analyzed using One-Way ANOVA and Repeated ANOVA. P <0.05 was considered statistically significant.
Results: The greatest color change (ΔE*) was observed at day 21 in TAP group (P < 0.001) followed by SDF group (P < 0.013), whereas Ca(OH)2 and Ca(OH)2 with CHX groups did not induce visible coronal discoloration.
Conclusions: Ca(OH)2 and Ca(OH)2 with the CHX groups showed the smallest coronal discoloration during the experimental time, whereas TAP and SDF groups showed the highest coronal discoloration.
Keywords: Calcium hydroxide, chlorhexidine, discoloration, silver diamine fluoride, spectrophotometer, triple antibiotic paste
|How to cite this article:|
Parikh AA, Nirupama D N, Naveen D N, Sindhu J, Nainan MT. Spectrophotometric analysis of crown discoloration induced by various intracanal medicaments: An in vitro study. Endodontology 2021;33:149-52
|How to cite this URL:|
Parikh AA, Nirupama D N, Naveen D N, Sindhu J, Nainan MT. Spectrophotometric analysis of crown discoloration induced by various intracanal medicaments: An in vitro study. Endodontology [serial online] 2021 [cited 2021 Dec 1];33:149-52. Available from: https://www.endodontologyonweb.org/text.asp?2021/33/3/149/327270
| Introduction|| |
Tooth discoloration is the most common side effect seen in endodontically treated teeth. Tooth discoloration is related to the contact period of the material to the tooth structure and the potential chromogenicity of the materials used in the treatment. The common causes of discoloration are pulpal hemorrhagic products, residual pulpal tissue, intracanal medicaments, obturating, and temporary filling materials. Although calcium hydroxide is the most widely used intracanal medicament for decades, it has limited effectiveness in the complete elimination of microorganisms from the root canal system.,
Studies have shown that, when calcium hydroxide is mixed with chlorhexidine (CHX), the antimicrobial activity is increased. When triple antibiotic paste (TAP) containing minocycline is used, promising results are seen in terms of antimicrobial activity. However, it presents with discoloration of the coronal tooth structure. Another effective intracanal medicament is silver diamine fluoride (SDF) against E. faecalis, but it shows a black staining of teeth when used to arrest the carious lesions.,,
Extensive research of existing literature did not reveal any study investigating crown discoloration induced by SDF and its comparison with other intracanal medicaments. Therefore, this study uses a spectrophotometric technique to assess the coronal discoloration potential of different intracanal medicaments. The null hypothesis of this study is that the tested intracanal medicaments would not affect the color of the crown.
| Materials and Methods|| |
Thirty single-rooted bovine incisors were collected and immersed in 0.5% Chloramine-T disinfectant solution (Merck, Darmstadt, Germany) for 48 h. Teeth were selected based on the average sum of their buccolingual and mesiodistal dimensions; the distance between the root canal wall and external root surface measured using a digital vernier caliper. The pulp tissue was removed, and irrigation was done with 10 ml 5.25% sodium hypochlorite (NaOCl), 10 ml 17% ethylene diamine tetraacetic acid (EDTA) for 2 min each followed by 10 ml distilled water. After drying with cotton, the pulp chamber was filled with temporary filling material (Cavit TM G, 3M ESPE, Germany) sealing up to 2 mm apical to the cement enamel junction (CEJ). A cotton pellet was placed loosely on the temporary filling material.
The specimens were randomly divided into five groups (n = 6), and intracanal medicament was placed into the canals [Table 1].
After placing the medicament in the canal, the apical openings were sealed with sticky wax. All the steps were performed from the apical aspect. Samples were stored at 100% humidity in an incubator at 37°C for 3 weeks.
In a dark room, color measurements were recorded pretreatment (pretreatment T0), at day 1 (T1), 7 (T7), 14 (T14), and 21 (T21), respectively, after placement of the medication. The color of each specimen was assessed by the CIE L*a*b* (Commission Internationale L'Eclairage, 1978) system using a spectrophotometer (Vita Easyshade Advance, VITA Zahnfabrik, Bad Sackingen, Germany) on the buccal surfaces of the crown. To standardize the color measurement, a circular tape of diameter 6 mm with a hole in the middle was bonded to the buccal surface of the crown 2 mm coronal to the CEJ [Figure 1]. The spectrophotometer was calibrated according to the manufacturer's instructions. Color measurement was performed three times, and the mean was calculated. L* represents the value of lightness or darkness, a* represents the measurement along the red-green axis, and b* represents the measurement along the yellow-blue axis. The total color differences (E*) were calculated using the following formula:
|Figure 1: Circular strip on the buccal surface of the crown above the cement enamel junction|
Click here to view
The L*, a*, and b* parameters of the samples were measured and compared to the pretreatment values. Descriptive statistics were represented with mean and standard deviation. ANOVA test was used to find significance among the groups. Repeated ANOVA was used to find significance in follow-up (within the group). P < 0.05 was considered statistically significant.
| Results|| |
The experimental groups did not have significantly different baseline L* (P = 0.966), a* (P = 0.900), and b* (P = 0.499). Interactions between time and materials demonstrated a significant effect on the values (ΔE*) in each experimental groups (P < 0.001, P < 0.009, P < 0.001, and P < 0.013) except the control group (P = 0.139) [Figure 2]. SDF and TAP induced visible coronal discoloration, whereas Ca(OH)2 and Ca(OH)2 with CHX groups did not induce visible coronal discoloration [Figure 3].
|Figure 2: The color change at different time periods in the groups. Group A: Control, Group B: Ca(OH)2, Group C: Ca(OH)2 with CHX, Group D: TAP Group E: SDF|
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|Figure 3: Discoloration of teeth on 21st day. Group A: Control, Group B: Ca(OH)2, Group C: Ca(OH)2 with CHX, Group D: Triple Antibiotic Paste, Group E: Silver Diamine Fluoride|
Click here to view
| Discussion|| |
The primary objective of this study was to assess the discoloration potential of four different intracanal medicaments.
In the present study at day 1, experimental groups, i.e. Ca(OH)2, Ca(OH)2 with CHX, TAP, and SDF did not induce statistically significant coronal discoloration. The evaluated endodontic filling materials provided ΔE* values higher than 3.7, which is the clinical threshold for acceptability of color differences, except the Ca(OH)2 group on day 1. The highest level of coronal discoloration occurred in the teeth filled with TAP reaching ΔE* =20.32 on day 21. The results of our study are in accordance with Akcay et al. Their results indicated that TAP with amoxicillin induced severe color changes from week 1 of evaluation. The mechanisms by which TAP induces coronal tooth discoloration is binding of minocycline to the calcium ions through chelation.,, Interestingly, in our study, teeth filled with SDF also resulted in clinically visible crown discoloration, reaching ΔE* =16.18 on day 21. The mechanisms by which SDF impacts coronal tooth discoloration may relate to silver deposits at tubular orifices after removal of the smear layer.,, However, there are no previous study data to compare coronal discoloration of Ca(OH)2, Ca(OH)2 with CHX, TAP, and SDF when used as intracanal medicament.
The rationale behind choosing bovine teeth to assess discoloration by various intracanal medicaments was based on the study by Schilke et al., who reported that, in bovine teeth, the number of dentinal tubules in coronal dentin did not significantly differ from the dentin of human teeth. In our study, all the procedures were performed from the apical aspect to avoid coronal microleakage of the intracanal medicament and prevent disruption of the intact crown., Using #45 H file, the pulp was removed in toto from the apical aspect. Moreover, to remove any remaining pulp tissue in the chamber, 5.25% NaOCl and 17% EDTA were used for irrigation. This was more predictable in the bovine model, which is another reason for the use of bovine teeth.
In this study, a digital spectrophotometer was used to register tooth shades at the different experimental phases. The spectrophotometer is commonly used for the measurement of transmitted or reflected light and moreover is suitable for color analysis of convex and asymmetric objects such as teeth, and are the reference tools for color assessment.,,
| Conclusion|| |
Within the limitation of the study, intracanal placement of Ca(OH)2 and Ca(OH)2 with CHX groups did not induce clinically visible crown discoloration until day 21, whereas TAP and SDF groups induced clinically visible crown discoloration from day 7 onward, after placement. Further studies are required on various substitutes and techniques so that the clinician can make an informed decision regarding the use of intracanal medicament, striking the right balance between the degree of coronal discoloration and antimicrobial efficacy, especially in teeth present in the esthetic zone.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Krastl G, Allgayer N, Lenherr P, Filippi A, Taneja P, Weiger R. Tooth discoloration induced by endodontic materials: A literature review. Dent Traumatol 2013;29:2-7.
Parsons JR, Walton RE, Ricks-Williamson L. In vitro
longitudinal assessment of coronal discoloration from endodontic sealers. J Endod 2001;27:699-702.
Ahmed HM, Abbott PV. Discoloration potential of endodontic procedures and material: A review. Int Endod J 2012;45:883-97.
Silveira CF, Cunha RS, Fontana CE, de Martin AS, Gomes BP, Motta RH, et al.
Assessment of the antibacterial activity of calcium hydroxide combined with chlorhexidine paste and other intracanal medications against bacterial pathogens. Eur J Dent 2011;5:1-7.
Balto KA. Calcium hydroxide has limited effectiveness in eliminating bacteria from human root canal. Evid Based Dent 2007;8:15-6.
Gomes BP, Vianna ME, Zaia AA, Almeida JF, Souza-Filho FJ, Ferraz CC. Chlorhexidine in endodontics. Braz Dent J 2013;24:89-102.
Ghabraei S, Marvi M, Bolhari B, Bagheri P. Minimum intracanal dressing time of triple antibiotic paste to eliminate enterococcus faecalis (ATCC 29212) and determination of minimum inhibitory concentration and minimum bactericidal concentration: An ex vivo
study. J Dent (Tehran) 2018;15:1-9.
Hiraishi N, Yiu CK, King NM, Tagami J, Tay FR. Antimicrobial efficacy of 3.8% silver diamine fluoride and its effect on root dentin. J Endod 2010;36:1026-9.
Al-Madi EM, Al-Jamie MA, Al-Owaid NM, Almohaimede AA, Al-Owid AM. Antibacterial efficacy of silver diamine fluoride as a root canal irrigant. Clin Exp Dent Res 2019;5:551-6.
Mathew VB, Madhusudhana K, Sivakumar N, Venugopal T, Reddy RK. Anti-microbial efficiency of silver diamine fluoride as an endodontic medicament – An ex vivo
study. Contemp Clin Dent 2012;3:262-4.
] [Full text]
Agahian F, Amirshahi SA, Amirshahi SH. Reconstruction of reflectances spectra using weighted principal component analysis. Color Res Appl 2008;33:360-71.
Paravina RD, Ghinea R, Herrera LJ, Bona AD, Igiel C, Linninger M, et al.
Color difference thresholds in dentistry. J Aesthet Restor Dent 2015;27:S1-9.
Akcay M, Arslan H, Yasa B, Kavrık F, Yasa E. Spectrophotometric analysis of crown discoloration induced by various antibiotic pastes used in revascularization. J Endod 2014;40:845-8.
Tanase S, Tsuchiya H, Yao J, Ohmoto S, Takagi N, Yoshida S. Reversed-phase ion-pair chromatographic analysis of tetracycline antibiotics. Application to discolored teeth. J Chromatogr B Biomed Sci Appl 1998;706:279-85.
Vijayaraghavan R, Mathian VM, Sundaram AM, Karunakaran R, Vinodh S. Triple antibiotic paste in root canal therapy. J Pharm Bioallied Sci 2012;4:S230-3.
Lee KW, Williams MC, Camps JJ, Pashley DH. Adhesion of endodontic sealer to dentin and gutta-percha. J Endod 2002;28:684-8.
Agrawal Vineet S, Rajesh M, Sonali K, Mukesh P. A contemporary overview of endodontic irrigant – A review. Austin J Dent App 2014;1:105-15.
Knight GM, McIntyre JM, Craig GG. An in vitro
model to measure the effect of a silver fluoride and potassium iodide treatment on the permeability of demineralized dentine to Streptococcus mutants
. Aust Dent J 2005;50:242-5.
Cumbo E, Melilli E, Gallina D; Giuseppe International. Irrigants in endodontics: A review. J Clin Dent 2019; 12:37-62.
Schilke R, Lisson JA, Bauss OS. Comparison of number and diameter of dentinal tubule in human and bovine dentine by scanning electron microscopic investigation. Arch Oral Biol 2000;45:355-61.
Fonseca RB, Haiter-Neto F, Fernandes-Neto AJ, Barbosa GA, Soares CJ. Radiodensity of enamel and dentin of human, bovine and swine teeth. Arch Oral Biol 2004;49:919-22.
Irala LE, Grazziotin-Soares R, Salles AA, Munari AZ, Pereira JS. Dissolution of bovine pulp tissue in solutions consisting of varying NaOCl concentrations and combined with EDTA. Braz Oral Res 2010;24:271-6.
Fairman HS, Brill MH. The principal components of reflectances. Color Res Appl 2004;29:104-10.
Dozić A, Kleverlaan CJ, El-Zohairy A, Feilzer AJ, Khashayar G. Performance of five commercially available tooth color-measuring devices. J Prosthodont 2007;16:93-100.
Usumez A, Ozturk N, Ozturk B. Two-year color changes of light-cured composites: Influence of different light-curing units. Oper Dent 2005;30:655-60.
JohnsenS. How to measure color using a spectrometer and calibrated photographs. J Exp Biol 2016;219:772-8.
Zoya A, Tewari RK, Mishra SK, Faisal SM, Ali S, Kumar A, et al.
Sodium percarbonate as a novel intracoronal bleaching agent: Assessment of the associated risk of cervical root resorption. Int Endod J 2019;52:701-8.
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