Journal of Research in Dental and Maxillofacial Sciences | |
Effects of cyclic loading on screw loosening, vertical misfit, and microleakage at the fixture-angulated abutment interface | |
article | |
N Naseri1  A Babasafari1  E Jalalian1  A Mazaheri1  A Zarbakhsh1  | |
[1] Prosthodontics Dept, Prosthodontics Dept, Faculty of Dentistry, Tehran Medical Sciences, Islamic Azad University | |
关键词: Dental Implants; Dental Implant-Abutment Design; Dental Leakage; | |
DOI : 10.52547/jrdms.6.4.1 | |
学科分类:社会科学、人文和艺术(综合) | |
来源: Islamic Azad University | |
【 摘 要 】
Background and Aim: This study assessed the effects of cyclic loading on screw loosening, vertical misfit, and microleakage at the fixture-angulated abutment interface. Materials and Methods: This in vitro study evaluated 12 implants in two groups (n=6). The implants were mounted in self-cure acrylic resin. The abutment screw was torqued to 30 N/cm by a digital torque-meter and re-torqued after 5 min. Six points at the fixture-abutment interface were inspected under a stereomicroscope (x75 magnification), and the distance between the two reference points was measured. Six implant-abutment assemblies then underwent cyclic loading (75 N, 1 Hz, 500,000 cycles) while the remaining six (control group) were stored at room temperature. The distance was measured again at the same 6 points after cyclic loading. Vertical misfit was calculated by subtracting the before and after values. The torque loss was measured by a digital torque-meter. The assemblies were then immersed in fuchsine and incubated at 37°C for 24 h. Next, the abutment was unscrewed and the fixtures were cut in half. The penetration depth of fuchsine was measured at 3 points of each fixture half under a stereomicroscope at x75 magnification, and the mean of the six measurements (entire fixture) was reported as the microleakage score of each sample. Data were analyzed using t-test. Results: Cyclic loading significantly increased the misfit (P=0.001) and microleakage (P=0.01), and decreased the detorque value (P=0.04). No case of screw loosening was noted in any group. Conclusion: Cyclic loading significantly increases the vertical misfit, microleakage, and torque loss.
【 授权许可】
CC BY
【 预 览 】
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RO202307110002398ZK.pdf | 341KB | download |