Disadvantages of In-Office Whitening. 1  In-office bleaching is more expensive than take-home alternatives. 2  Its cost, on average, is $650, compared to $400 for take-home trays and under $100 for over-the-counter bleaching trays or whitening strips.
Planetary protection is a guiding principle in the design of an interplanetary mission, aiming to prevent biological contamination of both the target celestial body and the Earth in the case of sample-return missions.
A planetary (or epicyclic if youâre British) gear set consists of a solid âsunâ gear, with teeth on the outside, a hollow âringâ gear with teeth on the inside, and some number of little planet gears rotating around the sun and also enmeshed with the ring gear.