Can having a filling lead to a cracked tooth?

Depends: Fillings usually last a long time. Silver fillings are more likely to crack teeth acting as a wedge and also expanding and contracting at a different rate than the tooth when exposed to hot (coffee) or cold (ice). While not filling teeth is not an option, teeth with fillings are weaker than natural teeth.

Many causes: Any time a tooth is stressed, either externally from biting pressures, bruxism, or a traumatic blow; or from internal stresses such as a cavity, a dental filling that expands and contracts differently from natural tooth structure, or an endodontically treated tooth with loss of vitality, it is more prone to tooth fracture. The larger the filling, the weaker the tooth, the greater the risk.

Not uncommon: A tooth restored with amalgam filling does not reinforce your teeth and it is common to see cracks and ultimately fractures of your teeth caused by the way the tooth is wedged with a metal filling between its cusp tips. Like any other filling, amalgam should be replaced with crown when cracks exist.