Bruxism is the posh word for grinding, clenching, or gritting your teeth together. With your real teeth, this is not an issue because the structure of your teeth allows them to absorb the shock created by bruxism. If you are prone to grinding or clenching your teeth, you may not be able to have dental implants because your new, implanted tooth will not have the structure which protects it from the pressure these actions produce. This will complicate the healing process and could damage your prosthetic teeth. This can be extremely expensive to repair.
A solution is wearing a special mouth guard made to wear at night.