Influence of erbium, chromium-doped: Yttrium scandium-gallium-garnet laser etching and traditional etching systems on depth of resin penetration in enamel: A confocal laser scanning electron microscope study

Abstract

Objective:This study was performed to assess the resin tag length penetration in enamel surface after bonding of brackets to identify which system was most efficient.Methodology:Our study was based on a more robust confocal microscopy for visualizing the resin tags in enamel. Totally, 100 extracted human first and second premolars have been selected for this study and were randomly divided into ten groups of 10 teeth each. In Group 1, the buccal enamel surface was etched with 37% phosphoric acid (3M ESPE), Group 2 with 37% phosphoric (Ultradent). In Groups 5, 6, and 7, erbium, chromium-doped: Yttrium scandium-gallium-garnet (Er, Cr: YSGG) laser (Biolase) was used for etching the using following specifications: Group 5 (1.5 W/20 Hz, 15 s), Group 6 (2 W/10 Hz, 15 s), and Group 7 (2 W/20 Hz, 15 s). In Groups 8, 9, and 10, Er, Cr: YSGG laser (Biolase) using same specifications and additional to this step, conventional etching on the buccal enamel surface was etched with 37% (3M ESPE) after laser etching. In Groups 1, 5, 6, 7, 8, 9, and 10 3M Unitek Transbond XT primer was mixed with Rhodamine B dye (Sigma-Aldrich, Germany) to etched surface and then cured for 20 s. In Group 2, Ultradents bonding agent was mixed with Rhodamine B. In Group 3, 3M Unitek Transbond PLUS, Monrovia, USA, which was mixed with Rhodamine B dye (Sigma-Aldrich, Germany). Group 4, with self-etching primer (Ultradent-Peak SE, USA) was mixed with Rhodamine B dye (Sigma-Aldrich, Germany). Later (3M Unitek, Transbond XT, Monrovia USA) [Figure 1] was used to bond the modified Begg brackets (T. P. Orthodontics) in Groups 1, 3, 5, 6, 7, 8, 9, and 10. In Groups 2, 4 Ultradent-Peak LC Bond was used to bond the modified brackets. After curing brackets were debonded, and enamel depth penetration was assessed using confocal laser scanning microscope.Results:Group J had a mean maximum depth of penetration of 100.876 μm, and Group D was the least having a maximum value of 44.254 μm.Conclusions:Laser alone groups had comparable depths of penetration to that of self-etching groups but much lower than conventional acid etched groups.

The clinical effects of laser preparation of tooth surfaces for fissure sealants placement: a systematic review and meta-analysis

“…Kumar et al [23] used a lower output (1.5 W) to etch enamel, per Berks and colleagues, and observed that Er, Cr: YSGG laser irradiations using 1 W, 1.5 W or 2 W produced etching patterns similar to those produced by etching with acid in the scanning electron microscope (SEM) study. While Vijayan et al [48] found that the enamel surfaces etched by Er, Cr: YSGG laser at 1.5 W/20 Hz, 2 W/10 Hz and 2 W/20 Hz, 2 W/20 Hz provided the best results with consistency in tag lengths and other studies found that it provided adequate bond strength. Moreover, in vitro studies have shown that the same parameters could result in different outcomes and different parameters could result in similar outcomes.…”

A Comparative Study Between Acid-etching and Er,Cr:YSGG Laser Irradiation on Enamel Surface Evaluated by OCT and SEM

“…Laser irradiation on the dental surface can protect the enamel against the carious attack, which is one of its advantages. Nevertheless, the use of Er,Cr:YSGG laser when treating enamel surfaces and dentin has been presenting diverse results when it comes to dental adhesion [1][2][3][4].…”

“…There has been a growing research interest in the conditioning effects of erbium, chromium:yttrium-scandiumgallium-garnet (Er,Cr:YSGG) laser on tooth surfaces. The etching effects of Er,Cr:YSGG laser on dental hard tissues have been investigated mostly via microleakage evaluation and mechanical tests made on composite restorations applied to primary and permanent tooth cavities [4].…”

Esem Analysis of Enamel Surface Morphology Etched With Er,cr:ysgg Laser and Phosphoric Acid: In Vitro Study

“…It causes surface roughening and irregularity similar to that of acid etching to a depth of 10 to 20 um, depending on the type of laser and the energy applied to the surface. [31] Thukral reported that ESEM analysis of enamel surface after Er.Cr.YSGG Laser irradiation showed the roughened enamel surfaces with intact morphology of the enamel prisms and complete absence of smear layer, so Laser-etching can be successfully used as an alternative to the conventional acid-etch. Skipping the step of acidetching also helps save chair-side time and the results of the laser etched tooth surface are superior or at least comparable to that of an acid etched tooth surface [32] .…”