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.
1 All Robots Are Unpredictable. 2  Debunked:The Planetary Protection Racket - Zubrin's Claim That There Is No Need To Protect Earth From Mars Microbes. 3  Smoking Is No Longer Cool Among American Kids - Peer Pressure Is Why. 4  A Narrow Escape From The Cumbre Rucu Volcano. 5  For Immune System Stem Cell Studies, Mice Aren't Enough.