Moreira Fernando César, Jacob Helder Baldi, Vaz Luis Geraldo, Guastaldi Antonio Carlos
Universidade Estadual Paulista, Faculdade de Odontologia, Departamento de Materiais Odontológicos e Prótese (Araraquara/SP, Brazil).
The University of Texas Health Science Center at Houston School of Dentistry, Department of Orthodontics (Houston/TX, USA).
Dental Press J Orthod. 2020 Jan-Feb;25(1):28-35. doi: 10.1590/2177-6709.25.1.028-035.oar.
The purpose of this study was to evaluate the effect of the Yd:YAG laser irradiation on orthodontic bracket base surface. Shear bond strength (SBS) values and sites of the bonding failure interfaces were quantified.
Brackets were divided into two groups: OP (One Piece - integral sandblast base) and OPL (One Piece - laser irradiation). The brackets were randomly bonded on an intact enamel surface of 40 bovine incisors. The SBS tests were carry out using a universal test machine. A stereomicroscopy was used to evaluate the adhesive remnant index (ARI), and surface characterization was performed by scanning electron microscopy (SEM). Student's t-test was used to compare the SBS between the two groups (p< 0.05). Frequencies and chi-square analysis were applied to evaluate the ARI scores.
OPL group showed higher value (p< 0.001) of SBS than OP group (43.95 MPa and 34.81 MPa, respectively). ARI showed significant difference (p< 0.001) between OPL group (ARI 0 = 100%) and OP group (ARI 0 = 15%). SEM showed a higher affinity between the adhesive and the irradiated laser base surface.
Yd:YAG laser irradiation on bracket base increased SBS values, showing that bonding failure occurs at the enamel/adhesive interface. Laser-etched bracket base may be used instead of conventional bases in cases where higher adhesion is required, reducing bracket-bonding failure.
本研究旨在评估钇铝石榴石（Yd:YAG）激光照射对正畸托槽基底表面的影响。对剪切粘结强度（SBS）值和粘结失败界面的部位进行量化。
将托槽分为两组：OP（一体式喷砂基底）和OPL（一体式激光照射）。将托槽随机粘结在40颗牛切牙的完整釉质表面。使用万能试验机进行SBS测试。使用体视显微镜评估粘结剂残留指数（ARI），并通过扫描电子显微镜（SEM）进行表面表征。采用学生t检验比较两组之间的SBS（p<0.05）。应用频率和卡方分析评估ARI评分。
OPL组的SBS值高于OP组（分别为43.95MPa和34.81MPa，p<0.001）。OPL组（ARI 0 = 100%）和OP组（ARI 0 = 15%）之间的ARI存在显著差异（p<0.001）。SEM显示粘结剂与激光照射的基底表面之间具有更高的亲和力。
对托槽基底进行Yd:YAG激光照射可提高SBS值，表明粘结失败发生在釉质/粘结剂界面。在需要更高粘结力的情况下，激光蚀刻托槽基底可替代传统基底，减少托槽粘结失败。
