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.
Sheldon James Plankton, or simply Plankton, is a character in the Nickelodeon animated television series SpongeBob SquarePants.Although usually an antagonist, he is frequently shown as a protagonist or an antihero. He is voiced by Mr. Lawrence and first appeared in the episode  Plankton!  on July 31, 1999.heldon James Plankton, or simply Plankton, is a character in the Nickelodeon animated television series SpongeBob SquarePants.
Related: Planktonic. plankton. Small organisms that float or drift in great numbers in bodies of salt or fresh water. Plankton is a primary food source for many animals, and consists of bacteria, protozoans, certain algae, cnidarians, tiny crustaceans such as copepods, and many other organisms. Compare benthos, nekton.