How bad does malocclusion need to be for my dentist to refer me to an orthodontist?

Depends: If you are unhappy with your dental function or appearance request that your dentist refer you to an orthodontist. Don't wait for them to suggest it.

Depends: If your bite doesn't feel right to you or you don't like something about the way your smile looks, then by all means don't wait for your dentist to refer you to an orthodontist. You may also want to visit an orthodontist or two near you to see what they have to say.

Any Malocclusion: "bad" is a subjective opinion. Your dentist should refer you to an orthodontist when he/she believes your malocclusion should be evaluated for correction.

Don't wait!: Don't rely on your dentist. If you even think you have a malocclusion go to find one on this website.

Problematic: If your dentist tells you to see an orthodontist she has diagnosed you with a malocclusion (bad bite). Go see an orthodontist for an initial examination (may be free) to learn the facts. Even if your dentist has not referred you, but you see something that does not look old feel right, go get an orthodontic opinion. You can then make decisions based on facts.

Depends: The better question is how bad does it have to be until you feel like you'd like it be to addressed?

Totally elective: Orthodontics is a personal choice. A dentist can bring it up as part of an overall plan to coordinate oral health, and it would likely be beneficial, but not a necessity. The threshold for a doctor to refer for treatment is different for everyone.