He added that the laser treatment also caused less damage to the rest of the teeth.

BBC: 'No need for dentist's drill'

The polymers return to a pre-defined shape when heated to a certain temperature, and, when damage is detected, an infrared laser sends light through the network to the damaged area, triggers the shape-memory, and commands the area to repair the crack or tear -- regaining up to 96 percent of its original strength.

ENGADGET: Shape-memory polymer knows when it's hurt, fixes itself

With graphene as a component instead of traditional materials, scientists could develop a laser as small as a pencil that's immune to thermal damage typically caused by intense beams.

ENGADGET

Current ultraviolet light laser treatments can kill micro-organisms - but cannot be used in humans as they would also damage cells in the body.

BBC: Cell infected with HIV