Yiğit Elif, Şahin Volkan
Department of Prosthodontics, Faculty of Dentistry, Kırıkkale University, Kırıkkale, Türkiye.
J Adv Prosthodont. 2025 Aug;17(4):210-223. doi: 10.4047/jap.2025.17.4.210. Epub 2025 Aug 19.
This study evaluated the fit of implant-supported bars fabricated using different computer-aided manufacturing (CAM) techniques.
A mandibular model with four dental implants (Nobel Replace Conical Connection, 3.5 mm × 11.5 mm) was fabricated using photoelastic resin. Sixteen Co-Cr implant-supported bars were produced using four CAM techniques: casting milled wax (CMW), selective laser sintering (SLS), dense milling (DM), and soft milling (SM) (n = 4). Fit was assessed through photoelastic stress analysis and digital scanning with a topographic digitizer (BreuckmannSmartScan). A standardized coordinate system was used for fit analysis. Data were analyzed using the Kruskal-Wallis test, with Dunn-Bonferroni for multiple comparisons (α = .05).
Photoelastic analysis showed that bars fabricated with DM exhibited the lowest stress levels, while SM showed moderate stress. Fit was significantly influenced by Δy-z, Δd, and Δd ( < .01), whereas Δhex and Δx-z had no significant effect ( > .05). The highest mean Δy-z value was observed in CMW (0.68 ± 0.28°) and the lowest in SLS (0.01 ± 0.34°). CMW had the highest Δd (-160.44 ± 61.17 µm) and DM the lowest (-5.46 ± 11.80 µm). DM showed the highest Δd (46.23 ± 39.32 µm), while SM had the lowest (-55.04 ± 35.06 µm), with significant differences among the techniques.
In conclusion, full-arch implant supported Co-Cr bars fabricated using the different CAM techniques exhibited clinically acceptable passive fit.
本研究评估了使用不同计算机辅助制造（CAM）技术制作的种植体支持杆的适合性。
使用光弹性树脂制作一个带有四颗牙种植体（诺贝尔Replace锥形连接，3.5毫米×11.5毫米）的下颌模型。使用四种CAM技术制作了16根钴铬合金种植体支持杆：铸模铣削蜡型（CMW）、选择性激光烧结（SLS）、密集铣削（DM）和软铣削（SM）（n = 4）。通过光弹性应力分析和使用地形数字化仪（Breuckmann SmartScan）进行数字扫描来评估适合性。使用标准化坐标系进行适合性分析。数据采用Kruskal-Wallis检验进行分析，多重比较采用Dunn-Bonferroni检验（α = 0.05）。
光弹性分析表明，DM制作的杆应力水平最低，而SM显示出中等应力。适合性受到Δy-z、Δd和Δd（<0.01）的显著影响，而Δhex和Δx-z没有显著影响（>0.05）。CMW中观察到的平均Δy-z值最高（0.68±0.28°），SLS中最低（0.01±0.34°）。CMW的Δd最高（-160.44±61.17微米），DM最低（-5.46±11.80微米）。DM的Δd最高（46.23±39.32微米），而SM最低（-55.04±35.06微米），不同技术之间存在显著差异。
总之，使用不同CAM技术制作的全牙弓种植体支持的钴铬合金杆表现出临床上可接受的被动适合性。
