What does it mean if my temp crown keeps falling off?

Several causes: You may be grinding your teeth, the temporary crown may be high, you may be eating too agressively (sticky or hard foods). The tooth may be short and non-retentive (ie not much to hold the temporary crown). Temporary crowns are usually held on with temporary cement, which is soft. If you are flossing, pull the floss out sideways instead of up and down.