Markarian Roberto Adrian, Galles Deborah Pedroso, Gomes França Fabiana Mantovani
Int J Oral Maxillofac Implants. 2018 January/February;33(1):127–136. doi: 10.11607/jomi.5588. Epub 2017 Jun 20.
To measure the microgap between dental implants and custom abutments fabricated using different computer-aided design/computer-aided manufacture (CAD/CAM) methods before and after mechanical cycling.
CAD software (Dental System, 3Shape) was used to design a custom abutment for a single-unit, screw-retained crown compatible with a 4.1-mm external hexagon dental implant. The resulting stereolithography file was sent for manufacturing using four CAD/CAM methods (n = 40): milling and sintering of zirconium dioxide (ZO group), cobalt-chromium (Co-Cr) sintered via selective laser melting (SLM group), fully sintered machined Co-Cr alloy (MM group), and machined and sintered agglutinated Co-Cr alloy powder (AM group). Prefabricated titanium abutments (TI group) were used as controls. Each abutment was placed on a dental implant measuring 4.1× 11 mm (SA411, SIN) inserted into an aluminum block. Measurements were taken using scanning electron microscopy (SEM) (×4,000) on four regions of the implant-abutment interface (IAI) and at a relative distance of 90 degrees from each other. The specimens were mechanically aged (1 million cycles, 2 Hz, 100 N, 37°C) and the IAI width was measured again using the same approach. Data were analyzed using two-way analysis of variance, followed by the Tukey test.
After mechanical cycling, the best adaptation results were obtained from the TI (2.29 ± 1.13 μm), AM (3.58 ± 1.80 μm), and MM (1.89 ± 0.98 μm) groups. A significantly worse adaptation outcome was observed for the SLM (18.40 ± 20.78 μm) and ZO (10.42 ± 0.80 μm) groups. Mechanical cycling had a marked effect only on the AM specimens, which significantly increased the microgap at the IAI.
Custom abutments fabricated using fully sintered machined Co-Cr alloy and machined and sintered agglutinated Co-Cr alloy powder demonstrated the best adaptation results at the IAI, similar to those obtained with commercial prefabricated titanium abutments after mechanical cycling. The adaptation of custom abutments made by means of SLM or milling and sintering of zirconium dioxide were worse both before and after mechanical cycling.
测量使用不同计算机辅助设计/计算机辅助制造（CAD/CAM）方法制作的定制基台与牙科种植体之间在机械循环前后的微间隙。
使用CAD软件（Dental System，3Shape）设计一种与4.1毫米外六角形牙科种植体兼容的单单位螺丝固位冠的定制基台。将生成的立体光刻文件发送出去，采用四种CAD/CAM方法进行制造（n = 40）：二氧化锆的铣削和烧结（ZO组）、通过选择性激光熔化烧结的钴铬合金（SLM组）、完全烧结加工的钴铬合金（MM组）以及加工并烧结的粘结钴铬合金粉末（AM组）。使用预制钛基台（TI组）作为对照。将每个基台放置在一个插入铝块中的4.1×11毫米牙科种植体（SA411，SIN）上。使用扫描电子显微镜（SEM）（×4,000）在种植体-基台界面（IAI）的四个区域且相互间隔90度的相对距离处进行测量。对标本进行机械老化（100万次循环，2赫兹，100牛，37°C），然后使用相同方法再次测量IAI宽度。使用双向方差分析进行数据分析，随后进行Tukey检验。
机械循环后，TI组（2.29±1.13微米）、AM组（3.58±1.80微米）和MM组（1.89±0.98微米）获得了最佳适配结果。观察到SLM组（18.40±20.78微米）和ZO组（10.42±0.80微米）的适配结果明显更差。机械循环仅对AM标本有显著影响，显著增加了IAI处的微间隙。
使用完全烧结加工的钴铬合金以及加工并烧结的粘结钴铬合金粉末制作的定制基台在IAI处显示出最佳适配结果，与机械循环后商业预制钛基台获得的结果相似。通过SLM或二氧化锆的铣削和烧结制作的定制基台在机械循环前后的适配性均较差。
