Ibarra R Nicole, Sáez Mackarena, Rojas Victor, Oyonarte Rodrigo
Department of Orthodontics, Faculty of Odontology, Universidad de los Andes, Santiago, Chile.
Eur Oral Res. 2023 May 4;57(2):96-102. doi: 10.26650/eor.20231163180.
To evaluate and compare shear bond strength (SBS) of new and recycled metallic brackets bonded to conditioned and reconditioned enamel, using two different adhesive materials.
72 extracted sound human premolars were randomly divided into 6 groups. Transbond XT light cured composite (LCC) and Fuji Ortho LC resin-modified glass ionomer (RMGI), were used as adhesive materials. In groups 1 and 2 (control), new brackets were bonded to sound premolars using either LCC or RMGI, respectively. In Groups 3 and 4, new brackets were bonded to reconditioned enamel; and in groups 5 and 6, sandblasted recycled brackets were rebonded to reconditioned enamel. After 5.000 thermal cycles between 5ºC and 55ºC, SBS was evaluated and adhesive remnant on the enamel assessed using the ARI index. Statistical analyses included Shapiro-Wilk, ANOVA, Fligner-Killeen ANOVA and Tukey tests.
The statistical analysis showed no significant difference in SBS comparing control and experimental groups for either new or recycled brackets (p = 0.848). The SBS was significantly higher in brackets bonded with LCC (15.7 MPa) than RMGI (11.6 MPa) (p = 0.006). Adhesive failure was the most frequent, with the adhesive remnant covering more than 50% of the bracket base.
No significant differences were observed in SBS using either new or recycled brackets, regardless of the dental surface treatment (conditioned or reconditioned). Significantly higher SBS values were obtained with LCC adhesive. Adhesive failure prevails in all groups.
使用两种不同的粘结材料，评估并比较新的和回收的金属托槽粘结到处理过的和重新处理过的牙釉质上的剪切粘结强度（SBS）。
将72颗拔除的健康人前磨牙随机分为6组。使用Transbond XT光固化复合树脂（LCC）和Fuji Ortho LC树脂改良玻璃离子水门汀（RMGI）作为粘结材料。在第1组和第2组（对照组）中，分别使用LCC或RMGI将新托槽粘结到健康前磨牙上。在第3组和第4组中，将新托槽粘结到重新处理过的牙釉质上；在第5组和第6组中，将喷砂处理过的回收托槽重新粘结到重新处理过的牙釉质上。在5℃至55℃之间进行5000次热循环后，评估SBS，并使用ARI指数评估牙釉质上的粘结残余物。统计分析包括Shapiro-Wilk检验、方差分析、Fligner-Killeen方差分析和Tukey检验。
统计分析表明，无论是新托槽还是回收托槽，对照组和实验组的SBS均无显著差异（p = 0.848）。用LCC粘结的托槽的SBS（15.7 MPa）显著高于用RMGI粘结的托槽（11.6 MPa）（p = 0.006）。粘结失败最为常见，粘结残余物覆盖托槽基底的50%以上。
无论牙面处理方式是处理过的还是重新处理过的，使用新托槽或回收托槽时，SBS均无显著差异。使用LCC粘结剂可获得显著更高的SBS值。所有组中均以粘结失败为主。
