Electric toothbrush head and circuit board. The circuit board (left) controls the rotation of the head (right). Regular toothbrushing helps prevent to

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Electric toothbrush head and circuit board. The circuit board (left) controls the rotation of the head (right). Regular toothbrushing helps prevent tooth decay.

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Size: 3400px × 4172px
Photo credit: © SHEILA TERRY/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

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