Different pulse modes of Er:YAG laser irradiation: effects on bond strength achieved with self-etching primers.
OBJECTIVE
The aim of this study was to compare the effects of different pulse modes of Er:YAG laser on shear bond strength (SBS) of orthodontic brackets bonded with self-etching primers (SEP) and phosphoric acid etching.


METHODS
A total of 120 human mandibular third molars were randomly assigned to 3 groups of 40 specimens depending on the bonding procedure to be used. The groups were divided into two subgroups according to the pulse mode of the erbium-doped yttrium aluminum garnet (Er:YAG) laser irradiation as medium-short pulse (MSP) mode and quantum-square pulse (QSP) mode at 120 mJ, 10 Hz, 1.2 W. In each subgroup, the mesio- or distobuccal tooth surfaces were randomly assigned as experimental or control sides. After surface preparation with different modes of Er:YAG laser on experimental side, whole buccal tooth surfaces were treated with phosphoric acid etching or two different SEPs. Then metallic brackets were bonded with Transbond XT (3 M Unitek, Monrovia, CA, USA) or Kurasper F (Kuraray, Okayama, Japan). SBS values and the amount of adhesive remaining on the tooth after debonding were assessed. One-way analysis of variance (ANOVA) was used to evaluate the changes in mean SBS between groups resulting from laser etching, followed by post hoc test of Tukey.


RESULTS
There were statistically significant differences between the experimental and control sides of all groups (p < 0.05).


CONCLUSIONS
Laser etching with QSP and MSP modes increases the SBS of metallic brackets and Er:YAG laser irradiation with QSP mode increases the SBS of SEPs.
Department of Orthodontics, Faculty of Dentistry, Selcuk University, Konya, Turkey.
Mehmet
M
Akin
Department of Orthodontics, Faculty of Dentistry, Izmir Katip Celebi University, Izmir, Turkey.
Ilknur
I
Veli
Department of Orthodontics, Faculty of Dentistry, Selcuk University, Konya, Turkey.
Emire Aybuke
EA
Erdur
Department of Orthodontics, Faculty of Dentistry, Bezmialem University, Istanbul, Turkey.
Sertac
S
Aksakalli
Department of Orthodontics, Faculty of Dentistry, Selcuk University, Konya, Turkey. tancanuysal@yahoo.com.|Department of Orthodontics, Faculty of Dentistry, Izmir Katip Celebi University, Izmir, Turkey. tancanuysal@yahoo.com.
Tancan
T
Uysal
D000134:Acid Etching, Dental / Q000379:methods*; D000268:Adhesiveness / Q000528:radiation effects; D003799:Dental Stress Analysis; D004307:Dose-Response Relationship, Radiation; D006801:Humans; D066298:In Vitro Techniques; D053844:Lasers, Solid-State; D055115:Light-Curing of Dental Adhesives / Q000379:methods*; D008422:Materials Testing; D008963:Molar / Q000737:chemistry* / Q000528:radiation effects; D016910:Orthodontic Brackets; D011829:Radiation Dosage; D019279:Resin Cements / Q000737:chemistry* / Q000528:radiation effects*; D013314:Stress, Mechanical; D013499:Surface Properties / Q000528:radiation effects; D013718:Tensile Strength / Q000528:radiation effects
D019279:Resin Cements
Bonding failure; Dental bonding; Metallic brackets; Orthodontic brackets; Shear bond strength