Table 6.
Life-cycle impact assessment results; summary of environmental burdens for the use of an Essix or a Hawley retainer.
| Impact Category | Units | Essix | Hawley |
|---|---|---|---|
| Non-carcinogenic effects | CTUh | 6.93E-09 | 9.69E-09 |
| Minerals and metals | kg Sb-eq | 4.22E-07 | 7.79E-07 |
| Freshwater ecotoxicity | CTU | 0.11191 | 0.08261 |
| Climate change total | kg CO2-eq | 0.10914 | 0.15337 |
| Freshwater eutrophication | kg P-eq | 2.34E-05 | 2.25E-05 |
| Respiratory effects—inorganic | Disease incidence | 3.32E-09 | 3.61E-09 |
| Photochemical ozone creation | kg NMVOC—eq | 0.00028 | 0.00037 |
| Terrestrial eutrophication | mol N-eq | 0.00081 | 0.00105 |
| Marine eutrophication | kg N-eq | 8.89E-05 | 0.00011 |
| Ozone layer depletion | kg CFC-11-eq | 3.13E-09 | 6.51E-09 |
| Ionizing radiation | kg U235-eq | 0.00585 | 0.00736 |
| Land use | Points | 1.07179 | 0.83699 |
| Freshwater terrestrial acidification | mol H+-eq | 0.00038 | 0.00066 |
| Fossils | MJ | 2.34237 | 2.44299 |
| Carcinogenic effects | CTUh | 1.57E-09 | 3.60E-09 |
| Dissipated water | m3 water-eq | 0.06575 | 0.0191 |