@article{3192372,
    title = "Roughness and wettability of aligner materials",
    author = "Suter, Fabienne and Zinelis, Spiros and Patcas, Raphael and Schatzle, and Marc and Eliades, George and Eliades, Theodore",
    journal = "AMERICAN JOURNAL OF ORTHODONTICS",
    year = "2020",
    volume = "47",
    number = "3",
    pages = "223-231",
    publisher = "SAGE Publications Ltd",
    issn = "0002-9416",
    doi = "10.1177/1465312520936702",
    keywords = "orthodontic aligners; 3D roughness; surface energy; wettability; plaque
retention",
    abstract = "Objective: The characterisation of surface roughness and energy of
contemporary thermoplastic materials used in manufacturing of
orthodontic aligners.
Design: In vitro, laboratory study.
Materials and methods: Four commercially available thermoplastic
materials were selected (CA-medium/CAM, Essix-copopyester/COP, Duran/DUR
and Erkodur/ERK). Five disks from each, as received, material were
tested and subjected to: (1) reflected light microscopy; (2) optical
profilometry for the estimation of Sa, Sz, Sq, Sdr, Sc, Sv surface
roughness parameters (n = 5); and (3) contact angle measurements with a
Zisman series of liquids for the estimation of critical surface tension
(gamma(C)), total work of adhesion (W-A), as well as the work of
adhesion due to polar (W-P) and dispersion (W-D) components employing
the Zisman method (n = 5/liquid). Thermoformed disks were prepared
against a dental stone model and the roughness parameters were
calculated again Statistical analysis was performed by one-way ANOVA/
Tukey multiple comparison test and t-test (a = 0.05).
Results: Microscopic and profilometric analyses revealed a smooth
surface texture in the as-received materials, but a very rough texture
after thermoforming, with insignificant differences within each state.
Significant differences in the as-received state were found in the
surface energy parameters; CAM showed the lowest gamma(C) and the
highest W-A, W-P, W-D, whereas ERK with the highest gamma(C)
demonstrated lower W-A. COP and DUR were ranked in an intermediate group
regarding gamma(C), with a statistically significant difference in W-A
between them, mainly attributed to the lower W-P of the former.
Conclusion: Given the differences in surface energy parameters and the
lack of roughness differences within the as received or thermoformed
groups, it may be concluded that variations in the plaque retaining
capacity are anticipated, determined by gamma(C), W-A and the W-P, W-D
components."
}