They have two incisors in the upper and lower jaw which grow continually and must be kept short by gnawing.

They have two incisors in the upper and lower jaw which grow continually and must be keep short by gnawing.

The first problem is resolved by the use of circuit breakers devices that can be reset after they have broken current flow.

Their diet is still limited, however, because most babies do not have molars or canines at this age and often have a limited number of incisors.

In these miniature circuit breakers, the current is run through a solenoid, and, in the event of excess current flow, the magnetic pull of the solenoid is sufficient to force open the circuit breaker's contacts (often indirectly through a tripping mechanism).