Comparative Evaluation of Laser Etching and Acid Etching: An in vitro Study
Varsha V Sobha, NK Sapna Varma, VV Ajith
Citation Information :
Sobha VV, Varma NS, Ajith V. Comparative Evaluation of Laser Etching and Acid Etching: An in vitro Study. Int J Laser Dent 2016; 6 (1):6-11.
Recent innovations in bonding propose laser ablation as an alternative method to acid etching.
Objectives
The objective of this study is to compare the effect of laser irradiation at medium-short pulse (MSP) mode, quantum-square pulse (QSP) mode, and acid etching on the shear bond strength (SBS) of orthodontic brackets to enamel.
Materials and methods
Forty-two premolars were allocated to three groups (14 each): (1) 37% phosphoric acid etching; (2) erbium-doped yttrium aluminum garnet (Er:YAG) laser etching with MSP mode; (3) Er:YAG laser etching with quantum-square pulse mode. Metallic brackets were bonded with Transbond XT. After photo polymerization, the SBS values were recorded with universal testing machine. Surface morphology was evaluated with scanning electron microscopy (SEM). The remaining adhesive was assessed using adhesive remnant index (ARI).
Results
Nonparametric test was used to analyze the statistical significance. A mean rank of 18.29 and 10.71 was obtained for QSP mode and acid etching with p = 0.015, 18.14; and 10.86 for MSP mode and acid etching with p = 0.019; and 14 and 15 for QSP mode and MSP mode with p = 0.748. Statistically significant difference was found between laser and acid-etched group. The SEM scan showed MSP mode with regular and uniform surface, like acid-etched sample, whereas QSP samples had irregular and severely rough surface. The ARI indicates that failure sites are mainly at the enamel/adhesive interface in the acid-etched and MSP mode group and at the bracket base/adhesive interface in QSP mode group.
Conclusion
Laser etching in MSP mode is a successful alternative to acid etching, and provides a safer debonding of the brackets from the enamel surface without causing fractures.
How to cite this article
Sobha VV, Varma NKS, Ajith VV. Comparative Evaluation of Laser Etching and Acid Etching: An in vitro Study. Int J Laser Dent 2016;6(1):6-11.
An evaluation of a light-curing composite for bracket placement. Eur J Orthod 1994 Dec;16(6):541-545.
A simple method of increasing the adhesion of acrylic filling materials to enamel surfaces. J Dent Res 1955 Dec;34(6):849-853.
A review of direct orthodontic bonding. Br J Orthod 1975;2:171-180.
Acid resistance of erbium-doped yttrium aluminum garnet laser-treated and phosphoric acid-etched enamels. Angle Orthod 2006 Nov;76(6):1052-1056.
Caries risk in teeth with orthodontic bands: a review. J Acad Gen Dent 1972 May;20(3):24-28.
Stimulated optical radiation in ruby. Nature 1960;187:493-494.
Laser beam effect on dental hard tissues. J Dent Res 1964;43:873.
Microtensile bond strength of an etch-and-rinse adhesive to enamel and dentin after Er:YAG laser pretreatment with different pulse durations. Lasers Med Sci 2012 Jan;27(1):15-21.
Bonding of composite resin to carbon dioxide laser-etched human enamel. Dent Mater 1994;10:162-166.
Caries inhibition around composite restorations by pulsed carbon dioxide laser application. Eur J Oral Sci 2005 Jun;113(3):239-244.
Super VSP Er:YAG pulses for fast and precise cavity preparation. J Oral Laser Appl 2004;4:171-173.
In vitro study of the variable square pulse Er:YAG laser cutting efficacy for apicectomy. Lasers Surg Med 2005 Jun;36(5):347-350.
SEM-evaluation of enamel surfaces after removal of fixed orthodontic appliances. Am J Dent 2003 Dec;16(6):390-394.
An electron microscopic evaluation of the enamel surface subsequent to various debonding procedures. Aust Dent J 1990 Jun;35(3):245-252.
Effect of enamel laser irradiation at different pulse settings on shear bond strength of orthodontic brackets. Angle Orthod 2013 Nov;83(6):973-980.
Buonocore memorial lecture. Adhesion to enamel and dentin: current status and future challenges. Oper Dent 2003 May-Jun;28(3):215-235.
Shear bond strength of bonding to enamel with different laser irradiation distances. Lasers Med Sci 2011 Mar;26(2):149-156.
Scanning electron microscopic study of laser-induced morphologic changes of a coated enamel surface. Lasers Surg Med 1990;10(5):458-462.
Enamel surface roughness analysis after laser ablation and acid-etching. J Oral Rehabil 1993 Mar;20(2):213-224.
Bond strengths of orthodontic bracket after acid-etched, Er:YAG laser-irradiated and combined treatment on enamel surface. Angle Orthod 2003 Oct;73(5):565-570.
Tensile bond strength of one-step self-etch adhesives to Er:YAG laser-irradiated and non-irradiated enamel. Dent Mater J 2008 May;27(3):386-391.
Laser etching of enamel for orthodontic bonding. Am J Orthod Dentofacial Orthop 2008 Aug;134(2):193-197.
Scanning electron microscopic observations of dentin surface conditioned with the Er:YAG laser. Dtsch Gesellschaft Laser Newsletter1997 Jan;8:6.
Differences in bonding to acid-etched or Er:YAG-laser-treated enamel and dentin surfaces. J Prosthet Dent 2000 Sep;84(3):280-288.
Laser etching of enamel for direct bonding with an Er,Cr:YSGG hydrokinetic laser system. Am J Orthod Dentofacial Orthop 2002 Dec;122(6):649-656.
In vitro evaluation of microleakage under orthodontic brackets using two different laser etching, self etching and acid etching methods. Lasers Med Sci 2010 Nov;25(6):811-816.
Lambert absorption coefficients of water in the infrared. J Opt Soc Am 1971 Oct;61(10):1316-1320.
Optical constants of water in the 200-nm to 200-microm wavelength region. Appl Opt 1973 Mar;12(3):555-563.
Optical properties of dental enamel at 9–11 μm derived from time-resolved radiometry. Special Topics IEEE J Quant Electr 1999;5:1083-1089.
Lipid analysis of human enamel and dentine. Arch Oral Biol 1974 Aug;19(8):729-731.
Adhesion of composite to enamel and dentin surfaces irradiated by IR laser pulses of 0.5-35 micros duration. J Biomed Mater Res B Appl Biomater 2006 Oct;79(1):193-201.
