Department of Prosthodontics, Propaedeutics and Dental Materials, School of Dentistry, Christian-Albrechts University at Kiel, Arnold-Heller-Straße 16, 24105, Kiel, Germany.
Clin Oral Investig. 2024 Nov 5;28(11):628. doi: 10.1007/s00784-024-06017-2.
The study investigated the influence of retention grooves and material thickness of the retainer wing on the retentive strength of resin-bonded attachments (RBAs).
Sixty-four extracted human molars were used. Each tooth received a preparation limited to the enamel for the retainer wings of the RBAs. The specimens were divided into eight groups, each containing eight specimens. The groups varied based on the number of conical retention grooves (0, 1, 2, or 4) and the thickness of the CoCr retainer wings (0.4 mm and 0.8 mm). Before testing the retentive strength of the RBAs, the specimens underwent 37,500 thermal cycles followed by dynamic loading of 1,200,000 cycles on the RBAs' patrices using a chewing simulator. The debonding test was conducted using a universal testing machine at a crosshead speed of 2 mm/min.
The mean retentive strength ranged from 326 ± 96 N to 440 ± 77 N. Only a small portion of specimens (10.9%) exhibited adhesive failure, while the remainder demonstrated cohesive failure within the tooth structure. Neither the number of retention grooves, the thickness of the retainer wings, nor the size of the bonding surface significantly affected retentive strength.
The findings suggest that reducing the number of retention grooves and the material thickness does not influence the retentive strength of RBAs.
The retention of RBAs appears promising, supporting the clinical application of this treatment modality.
本研究旨在探讨固位翼的保留槽和材料厚度对树脂粘结附着体（RBA）固位力的影响。
使用 64 颗离体人磨牙。每颗牙均接受仅限于粘结翼的牙釉质预备。标本分为 8 组，每组 8 个标本。组间的差异在于锥形保留槽的数量（0、1、2 或 4）和 CoCr 固位翼的厚度（0.4mm 和 0.8mm）。在测试 RBA 的固位力之前，将标本进行 37500 次热循环，然后使用咀嚼模拟器对 RBA 的基底进行 120 万次动态加载。使用万能试验机以 2mm/min 的十字头速度进行离胶试验。
平均固位力范围为 326±96N 至 440±77N。仅有一小部分标本（10.9%）表现出粘固失败，而其余标本则在牙体结构内表现出内聚性失败。保留槽的数量、固位翼的厚度以及粘结面的大小均未显著影响固位力。
研究结果表明，减少保留槽的数量和材料厚度不会影响 RBA 的固位力。
RBA 的保留效果令人满意，支持该治疗方法的临床应用。
