Following a 20 s etching with 35%% phosphoric acid (Ultra Etch, Ultradent, USA) molar tubes (ERA, Farfield, USA) were bonded directly, using chemical-cure orthodontic adhesive (Unite, 3M, USA), similarly to the clinical conditions: at the centre of each buccal surface, parallel to the long axis of the crown.
Metal brackets (NANDA, Ortho Organizers, CA, USA) were bonded to the buccal surfaces of all teeth.
The constructed RPEs were bonded to the metal teeth using composite cement (ULTRA BAND-LOCK, Reliance, USA) and light-cured using an LED curing light (Elipar Freelight 2, 3M Espe, wavelength 430 ÷ 480 nm, intensity 1200 mW/mm2) for 30 s from the occlusal surface, the most effective method of bonding bands with this type of bonding agent [29].
Three types of commercially available prosthodontic resin composites [BelleGlass®, (BG, Kerr, CA, USA), Sinfony® (SF, 3 M ESPE, Dental Products, Germany), and GC Gradia® (GCG, GC Corp ,Tokyo, Japan)] were bonded to the alumina substrate using four different adhesive resins.
To bond PDMS parts, they were rinsed with ethanol, dried, and bonded using an air plasma (90 s, 30 W, 500 mTorr, PDC-002, Harrick Plasma, USA), and cured in an oven at 90°C for 2 h.
The adhesive system, Adper Single Bond 2 (3 M/ESPE – St . Paul Mn, USA), was applied using two consecutive coats, gentle air-dried for 5 s, and light cured for 10 s with a halogen light (Optilux – Kerr Dental, Orange, CA, USA), with an intensity of 600 measuredmeasured with the SDS radiometer (Kerr Dental, Orange, CA, USA).
In-house Python scripts based on Openeye's OEToolkit (Openeye, Santa Fe, USA) were used for compound manipulation and calculating descriptors for the number of heavy atoms, hydrogen-bond donors and acceptors, ring systems, and rotatable bonds.
(Bio-Rad Laboratories, USA) were used.
Briefly, anti-CD138 mouse monoclonal antibody (Dako, Carpinteria, CA, USA) was used at a 1/1200 dilution and was detected using Bond Polymer Refine Red Detection kit (Leica Biosystems, Buffalo Groves, IL, USA).
The X-ray photoelectron spectroscope (XPS; MultiLab 2000, Thermo, Pittsburgh, PA, USA) was used to analyze the chemical bonds of the CNTs. Figure 3a,b shows the XPS spectra of the C 1 s state for all of the CNT samples.
