Korean J Orthod.  2019 Jan;49(1):12-20. 10.4041/kjod.2019.49.1.12.

Surface analysis of metal clips of ceramic self-ligating brackets

• Kim KS
• Han SJ
• Lee TH
• Park TJ
• Choi S
• Kang YG
• Park KH

• KMID: 2431076
• DOI: http://doi.org/10.4041/kjod.2019.49.1.12

Abstract

OBJECTIVE
The aim of this study was to analyze the surface composition, roughness, and relative friction of metal clips from various ceramic self-ligating brackets.
METHODS
Six kinds of brackets were examined. The control group (mC) consisted of interactive metal self-ligating brackets while the experimental group (CC, EC, MA, QK, and WA) consisted of interactive ceramic self-ligating brackets. Atomic force microscopy-lateral force microscopy and scanning electron microscopy-energy-dispersive X-ray spectroscopy were used to analyze the surface of each bracket clip.
RESULTS
All the clips in the experimental groups were coated with rhodium except for the QK clip. The results showed that the QK clip had the lowest average roughness on the outer surface, followed by the MA, EC, WA, and CC clips. However, the CC clip had the lowest average roughness on the inner surface, followed by the QK, WA, MA, and EC clips. The QK clip also had the lowest relative friction on the outer surface, followed by the MA, EC, CC, and WA clips. Likewise, the CC clip had the lowest relative friction on the inner surface, followed by the QK, WA, MA, and EC clips.
CONCLUSIONS
The surface roughness and relative friction of the rhodium-coated clips were generally higher than those of the uncoated clips.

Keyword

Self-ligating bracket; Rhodium coating; Surface roughness

MeSH Terms

Ceramics*
Friction
Microscopy, Atomic Force
Rhodium
Spectrum Analysis
Rhodium

Figure

• 

  Figure 1 Images of (A) the control group and (B–F) the experimental groups. The closed and open clips for each bracket are shown on the left and right, respectively. A, Mini-Clippy® (Tomy, Tokyo, Japan); B, Clippy-C® (Tomy); C, Empower clear® (American Orthodontics, Sheboygan, WI, USA); D, MACH® (World Bio Tech, Seongnam, Korea); E, QuicKlear® (Forestadent, Pforzheim, Germany); F, WOW-A® (Hubit, Uiwang, Korea).

• 

  Figure 2 Optical microscopic images (left, 500×) and atomic force microscopy images (right) of the outer surfaces of A, mini-Clippy® (Tomy, Tokyo, Japan); B, Clippy-C® (Tomy); C, Empower clear® (American Orthodontics, Sheboygan, WI, USA); D, MACH® (World Bio Tech, Seongnam, Korea); E, QuicKlear® (Forestadent, Pforzheim, Germany); F, WOW-A® (Hubit, Uiwang, Korea).

• 

  Figure 3 Optical microscopic images (left, 500×) and atomic force microscopy images (right) of the inner surfaces of A, mini-Clippy® (Tomy, Tokyo, Japan); B, Clippy-C® (Tomy); C, Empower clear® (American Orthodontics, Sheboygan, WI, USA); D, MACH® (World Bio Tech, Seongnam, Korea); E, QuicKlear® (Forestadent, Pforzheim, Germany); F, WOW-A® (Hubit, Uiwang, Korea).

• 

  Figure 4 A, Commercial atomic force microscopy (AFM) system (TT-AFM; Probes Inc., Seoul, Korea). B, A schematic of the AFM imaging system.

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