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.
Plankton's voice is provided by American actor Mr. Lawrence. The voice Lawrence uses for Plankton originated as an imitation of one of his deep-voiced friends from high school. On television, he first used the voice for incidental characters on Rocko's Modern Life.