Private practice orthodontist, Tehran, Iran.
School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Int Orthod. 2022 Jun;20(2):100640. doi: 10.1016/j.ortho.2022.100640. Epub 2022 May 30.
Orthodontic brackets are increasingly bonded to the surface of zirconium crowns due to the growing aesthetic demands in adults' restorations. Therefore, providing a reliable bond between these substrates is of great importance. This study aimed at investigating the shear bond strength (SBS) of orthodontic metal brackets bonded to zirconium treated by sandblasting. In addition, the value was compared with SBS between metal brackets and enamel.
Samples were divided into three groups including first premolar enamel specimens (n=20), untreated zirconium blocks (n=20) and sandblasted zirconium blocks (n=20). Enamel specimens underwent etching and bonding procedures using 37% phosphoric acid and 3M™ Scotchbond™ Universal adhesive. Zirconium blocks were randomly allocated to two groups. The first group was prepared by sandblasting with 50μm aluminium oxide particles (AlO) under 4 bars pressure followed by bonding brackets with 3M™ Scotchbond™ Universal adhesive. Metal brackets were also bonded to the untreated zirconium group using the same adhesive. All samples underwent thermocycling, and SBS was calculated using a universal testing machine with a crosshead speed of 1mm/min. Data were analysed using One-way Anova and Tukey's tests.
The highest SBS was recorded in sandblasted zirconium group (26.17±8.22MPa) followed by enamel group (23.667±7.00MPa) and untreated zirconium group (11.49±7.00MPa). There was a significant difference between the SBS of untreated zirconium and that of two other groups.
Perfect SBS was achieved by sandblasting pre-treatment, comparable to that of enamel. Therefore, sandblasting of zirconium crowns is recommended prior to bonding orthodontic brackets.
由于成人修复体的审美需求不断增加，正畸托槽越来越多地粘结在氧化锆冠的表面。因此，在这些基底之间提供可靠的粘结非常重要。本研究旨在研究喷砂处理后的氧化锆粘结正畸金属托槽的剪切粘结强度（SBS）。此外，还比较了金属托槽和釉质之间的 SBS 值。
样本分为三组，包括第一前磨牙釉质标本（n=20）、未经处理的氧化锆块（n=20）和喷砂处理的氧化锆块（n=20）。釉质标本经 37%磷酸酸蚀和 3M Scotchbond Universal 胶粘剂粘结。氧化锆块随机分为两组。第一组用 50μm 氧化铝颗粒（AlO）在 4 巴压力下喷砂处理，然后用 3M Scotchbond Universal 胶粘剂粘结托槽。金属托槽也用相同的胶粘剂粘结到未经处理的氧化锆组。所有样本均进行热循环，SBS 用十字头速度为 1mm/min 的万能试验机计算。数据采用单因素方差分析和 Tukey 检验进行分析。
喷砂处理的氧化锆组的 SBS 最高（26.17±8.22MPa），其次是釉质组（23.667±7.00MPa）和未经处理的氧化锆组（11.49±7.00MPa）。未经处理的氧化锆和其他两组的 SBS 有显著差异。
喷砂预处理可获得理想的 SBS，与釉质相当。因此，建议在粘结正畸托槽前对氧化锆冠进行喷砂处理。
