A tooth filling may fall out due to several reasons:
- Decay: New decay around or beneath the filling can weaken its bond and cause it to dislodge.
- Wear and Tear: Over time, fillings can wear down due to normal chewing and grinding forces, especially if the filling is old or not properly placed.
- Improper Placement: If the filling was not properly placed or the cavity was not adequately cleaned before filling, it may not adhere well and could fall out.
- Trauma: Physical trauma or injury to the tooth can cause the filling to become loose or fall out.