Table 1.
Technical data (supplier specifications) and cytotoxicity (experimental outcomes) of the most common materials used for thermoformed (T) and directly printed (P) clear aligners.
| Brand | Material Composition | Density (g/cm3) | Elastic Modulus (MPa) | Tensile Stress (MPa) | Elongation at Break (%) |
Cell Viability (%) |
Cytotoxicity |
|---|---|---|---|---|---|---|---|
|
Duran (Scheu-Dental GmbH)
(T) |
Polyethylene terephthalate glycol (PET-G) | 1.27 | 2200 | 53 | >40 | 84.6 (Day 14) | Slight |
|
Biolon
(Dreve Dentamid GmbH) (T) |
Polyethylene terephthalate glycol (PET-G) | 1.27 | 2020 | 45 | >35 | 64.6 (Day 14) | Slight |
|
Zendura
(Bay Material LLC) (T) |
Polyurethane resin (PU) | 1.203 | - | - | - | 74.4 (Day 14) | Slight |
|
SmartTrack (Align Technology)
(T) |
Multilayer aromatic thermoplastic polyurethane/copolyester | - | - | - | - | 94.1 (Day 7) 78.8 (Day 14) |
Slight |
|
Dental LT (Formlabs Inc.)
(P) |
Photo polymeric clear methacrylate oligomer and glycol methacrylate | 1.1 1.3 |
2300 | 84 | 12 | 60.3 (Day 1) 62.5 (Day 14) |
Slight |
| Accura 60 SLA (3D System) (P) | Polycarbonate-based photo-polymeric resin | 1.13 1.21 |
2690–3100 | 58–68 | 5–13 | 13.9 (Day 1) 24.5 (Day 7) |
Severe |
|
E-Guard
(EnvisionTEC) (P) |
Photo-polymeric clear resin | 1.06 1.12 |
2050–2130 | 79–85 | 3.81 | 64.1 (Day 1) 75.1 (Day 7) |
Slight |