Romano Fábio Lourenço, Pessoti Giovanna, Galo Rodrigo, Gomes-Silva Jaciara Miranda, Lucisano Marília Pacífico, Borsatto Maria Cristina, Nelson-Filho Paulo
Professor, Universidade de São Paulo, Ribeirão Preto Dental School, Department of Pediatric Clinics, Ribeirão Preto/SP, Brazil.
Dental surgeon, Universidade de São Paulo, Ribeirão Preto Dental School, Ribeirão Preto/SP, Brazil.
Dental Press J Orthod. 2017 Mar-Apr;22(2):55-60. doi: 10.1590/2177-6709.22.2.055-060.oar.
: The aim of this study was to assess in vitro the influence of the CO2 laser and of the type of ceramic bracket on the shear bond strength (SBS) to enamel.
: A total of 60 enamel test surfaces were obtained from bovine incisors and randomly assigned to two groups, according to the ceramic bracket used: Allure (A); Transcend (T). Each group was divided into 2 subgroups (n = 15): L, laser (10W, 3s); C, no laser, or control. Twenty-four hours after the bonding protocol using Transbond XT, SBS was tested at a crosshead speed of 0.5 mm/min in a universal testing machine. After debonding, the Adhesive Remnant Index (ARI) was evaluated at 10 x magnification and compared among the groups. Data were analyzed by one-way ANOVA, Tukey's, Mann-Whitney's and Kruskal-Wallis tests (α = 0.05).
: Mean SBS in MPa were: AL = 0.88 ± 0.84; AC = 12.22 ± 3.45; TL = 12.10 ± 5.11; TC = 17.71 ± 6.16. ARI analysis showed that 73% of the specimens presented the entire adhesive remaining on the tooth surfaces (score 3). TC group presented significantly higher SBS than the other groups. The lased specimens showed significantly lower bond strength than the non-lased groups for both tested brackets.
: CO2 laser irradiation decreased SBS values of the polycrystalline ceramic brackets, mainly Allure.
本研究旨在体外评估二氧化碳激光和陶瓷托槽类型对牙釉质剪切粘结强度（SBS）的影响。
从牛切牙获取60个牙釉质测试表面，根据使用的陶瓷托槽随机分为两组：Allure（A）；Transcend（T）。每组再分为2个亚组（n = 15）：L，激光组（10W，3秒）；C，无激光组，即对照组。使用Transbond XT进行粘结操作24小时后，在万能试验机上以0.5毫米/分钟的十字头速度测试SBS。脱粘后，在10倍放大倍数下评估粘结剂残留指数（ARI），并在各组之间进行比较。数据采用单因素方差分析、Tukey检验、Mann-Whitney检验和Kruskal-Wallis检验进行分析（α = 0.05）。
以MPa为单位的平均SBS为：AL = 0.88 ± 0.84；AC = 12.22 ± 3.45；TL = 12.10 ± 5.11；TC = 17.71 ± 6.16。ARI分析表明，73%的标本在牙齿表面留有全部粘结剂（评分为3）。TC组的SBS显著高于其他组。对于两种测试托槽，激光照射的标本粘结强度均显著低于未照射组。
二氧化碳激光照射降低了多晶陶瓷托槽的SBS值，主要是Allure托槽。
