9
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Comparative evaluation of surface topography of tooth prepared using erbium, chromium: Yttrium, scandium, gallium, garnet laser and bur and its clinical implications

      research-article

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Background:

          Erbium, chromium: Yttrium, scandium, gallium, garnet (Er, Cr: YSGG) laser has been successfully used in the ablation of dental hard and soft tissues. It has been reported that this system is also useful for preparing tooth surfaces and etching, but no consensus exist in the literature regarding the advantage of lasers over conventional tooth preparation technique.

          Materials and Methods:

          Labial surfaces of 25 extracted human maxillary central incisors were divided into two halves. Right half was prepared with diamond bur and left half with Er, Cr; YSGG laser and a reduction of 0.3–0.5 mm was carried out. Topography of prepared surfaces of five teeth were examined under scanning electron microscope (SEM). The remaining samples were divided into 4 groups of 10 specimens each based on the surface treatment received: One group was acid etched and other was nonetched. Composite resin cylinders were bonded on prepared surfaces and shear bond strength was assessed using a universal testing machine.

          Results:

          The SEM observation revealed that the laser prepared surfaces were clean, highly irregular and devoid of a smear layer. Bur prepared surfaces were relatively smooth but covered with smear layer.

          Highest bond strength was shown by laser prepared acid etched group, followed by bur prepared the acid etched group. The bur prepared nonacid etched group showed least bond strength.

          Conclusions:

          Er, Cr: YSGG laser can be used for preparing tooth and bond strength value achieved by laser preparation alone without surface treatment procedure lies in the range of clinical acceptability.

          Related collections

          Most cited references25

          • Record: found
          • Abstract: found
          • Article: not found

          Differences in bonding to acid-etched or Er:YAG-laser-treated enamel and dentin surfaces.

          Er:YAG (erbium-doped yttrium aluminium garnet) lasers have been effective in the removal of dental tissues. It has been suggested that they are also useful for preparing dental surfaces for adhesion, but results to date have been controversial. This study compared the tensile strength of bracket-tooth bonds obtained after preparation of the surface for adhesion (dentin or enamel) by conventional acid-etching or by Er:YAG laser etching and investigated microstructure of resin-tooth interfaces using the 2 procedures. Eighty healthy human premolars were used. Brackets were cemented to acid-etched enamel, laser-etched enamel, acid-etched dentin, or laser-etched dentin (20 teeth per group). Dentin was previously exposed using a high-speed handpiece. Acid-etching was with 37% orthophosphoric acid (15 seconds for enamel, 5 seconds for dentin). Laser etching was with Er:YAG laser (four 200 mJ pulses per second for enamel; four 160 mJ pulses per second for dentin). Brackets were bonded with autocuring resin paste, having first applied a primer (dentin only) and then light-cured bonding resin. Tensile strength was determined with a universal testing machine. Data were analyzed with 2-way ANOVA and subsequent t test with Bonferroni correction. Fracture patterns were compared by the Wilcoxon test with Bonferroni correction. For SEM studies of the resin-tooth interface, a total of 12 premolars were used (3 for each tissue per treatment combination). Mean tensile bond strength for acid-etched enamel (14.05 +/- 5.03 MPa) was significantly higher (P<.05) than for laser-etched enamel (8.45 +/- 3.07 MPa), and significantly higher (P<.05) for acid-etched dentin (4.70 +/- 2.50 MPa) than laser-etched dentin (2.48 +/- 1.94 MPa). Bond failure after laser etching was due to microcohesive fracture of tooth tissue. SEM studies of both resin-enamel and resin-dentin interfaces indicated extensive subsurface fissuring after laser etching. Adhesion to dental hard tissues after Er:YAG laser etching is inferior to that obtained after conventional acid etching. Enamel and dentin surfaces prepared by Er:YAG laser etching show extensive subsurface fissuring that is unfavorable to adhesion.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Laser etching of enamel for direct bonding with an Er,Cr:YSGG hydrokinetic laser system.

            Irradiation of enamel with laser energy changes the physical and chemical characteristics of the enamel surface, and these alterations hold promise for the conditioning of enamel for bonding procedures. This laboratory study examined the influence of laser irradiation of enamel at 2 different power settings with an erbium, chromium: yttrium, scandium, gallium, garnet (Er,Cr:YSGG) hydrokinetic laser system (Millennium System, Biolase Technology, Inc; San Clemente, Calif) on the shear bond strength of orthodontic appliances and compared these with that of acid-etching. The prepared surfaces of 40 noncarious, intact, extracted premolars were exposed to laser energy: 20 teeth at 2-W setting (5.6 J/cm(2)) and 20 teeth at 1-W setting (2.7 J/cm(2)) of the commercial laser unit. Twenty teeth were etched with 37% orthophosphoric acid. Brackets were bonded with an orthodontic no-mix adhesive, and shear bond strength was determined with a universal testing machine. Data were analyzed with Kruskal-Wallis and Mann-Whitney U tests. Etched and restored surfaces of an acid-etched tooth and a 2-W laser-irradiated tooth were examined with scanning electron microscopy (SEM). Laser treatment under 2 W resulted in bond strengths of 7.11 +/- 4.56 megapascals (MPa), which was not significantly different from that of acid etching (8.23 +/- 2.30 MPa). Laser irradiation at 1 W resulted in bond strengths of 5.64 +/- 3.19 MPa, which was significantly different from that of acid etching (P <.05). However, large SD and coefficient of variation values of both laser groups made reliability of this method as an enamel conditioner questionable. Scanning electron microscopy studies of the restored irradiated surfaces showed good surface characteristics, whereas the lased surface was still more irregular than the restored acid-etched sample. Although laser devices are effectively used in some other areas of dentistry, enamel conditioning with an Er,Cr:YSGG laser cannot be considered a successful alternative to the conventional methods of increasing bond strengths to enamel.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Wet versus dry enamel ablation by Er:YAG laser.

              The purpose of this study was to observe tooth structure and pulpal temperature changes in extracted human teeth subjected to a pulsed Er:YAG (2.94 microns) laser. Two teeth were irradiated while dry and three teeth while moistened by a fine water mist. When the dry teeth were irradiated, there was minimal enamel ablation. SEM of the resulting surface showed rounded fragments of enamel rods, enamel melting, cracks, and smooth-edged voids. Intrapulpal temperature measured by thermal sensor rose more than 27 degrees C. When the laser application on the teeth was pulsed with a constant fine water mist, enamel and dentin were efficiently ablated. SEM of the resulting surfaces showed fissures and conical craters with sharp enamel projections remaining. Intrapulpal temperatures rose an average of 4 degrees C. These results indicate that pulsed Er:YAG (2.94 microns) used with a water mist removes enamel and dentin without producing significant pulpal temperature changes.
                Bookmark

                Author and article information

                Journal
                J Indian Prosthodont Soc
                J Indian Prosthodont Soc
                JIPS
                The Journal of the Indian Prosthodontic Society
                Medknow Publications & Media Pvt Ltd (India )
                0972-4052
                1998-4057
                Jan-Mar 2015
                : 15
                : 1
                : 23-28
                Affiliations
                [1]Department of Prosthodontics, Crown and Bridge, Maulana Azad Institute of Dental Sciences, New Delhi, India
                Author notes
                Address for correspondence: Dr. Pooja Kumari, Department of Prosthodontics, Crown and Bridge, Maulana Azad Institute of Dental Sciences, New Delhi, India. E-mail: pooja_pathak4@ 123456yahoo.in
                Article
                JIPS-15-23
                10.4103/0972-4052.155042
                4762284
                26929482
                326b1fb1-62a6-41c1-8b87-7e48a1978bff
                Copyright: © 2015 The Journal of Indian Prosthodontic Society

                This is an open access article distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 License, which allows others to remix, tweak, and build upon the work non-commercially, as long as the author is credited and the new creations are licensed under the identical terms.

                History
                : 25 July 2014
                : 21 December 2014
                Categories
                Original Article

                acid etching,bond strength,erbium,chromium: yttrium,scandium,gallium,garnet laser,laser etching,scanning electron microscope

                Comments

                Comment on this article