A small part of old filling for tooth fell off. dentist discourage refilling and wants to do crown. no insurance so what is best?

Pay the piper: This is very common in dentistry. Usually an old filling fails and more tooth structure is lost. From then on the frequency of failure increasese exponentially. Your best move is to go ahead and get the crown. You will save money in the long run.

Talk with doc: Tongue can be deceptive when it comes to judging size and direction, so it is possible that what you feel as a small piece is actually large (the % of fill to overall size of tooth is what's important). If the fill is substantial your doc will recommend a crown. Talk with your doc and discuss your payment options, most dentists are happy to help structure financing.

Porcelain onlay: As your tooth is highly structurally compromised, large fillings don't work for long. Why did the tooth break? Even crowns won't work with a bad bite. We often downplay the significance of (stress) fracture lines since they do not hurt. I do very few crowns, but many porcelain onlays, to save as much of your own tooth as possible, after i rebuild it internally. I prefer one visit cerec if i can.