I have the 4 upper teeth root canal and crowns put on.
One of the crowns broke a few month after, then the dentist remove all the crowns and put a temporaries until the new one came.
After I got the second set of crowns put on, last it about 4 months then happen again on one of the crowns a big chip came off then I call the dentist again and he say that I need another set again. I have the 3rd set of crowns put on but now 8 months after a big chip on the apper half of the front crown came off again! So this is the number 4 set of porcelain crowns.
The dentis has to hammer of the crowns off all the time that he replace it and is a lot of trauma on my jaw bone.
Can some body tell me if this is comon for the porcelain crowns fused to gold (is wath the dentist say and charge for)
Please help.

Your crowns should not be breaking or chipping if they are good porcelain, fused to gold. Sounds like shoddy dentistry (although I don't think your dentist makes them; he has to send them out to a lab). Someone along the line is trying to save money.

I think that is horrendous ! Four sets of crowns not properly done !

Tick

You should not be paying for the remade crowns. If he is sending it out to a lab... he needs to switch. If he is making them, you need to go elsewhere. Pay for the new set and sue him for the difference in price. (saw a case just like this on peoples court)

Definitely something is wrong! I'd ask for ALL your money back and make an appointment with a prosthodontist (specializes in crown and bridge work).
Perhaps the dentist needs to take more time with checking your bite. He MUST send the lab models of your upper and lower teeth as they were BEFORE they were prepped for the crowns. This way the lab can be sure that the crowns come together properly with the lower teeth. The lab can only work with what the dentist sends them.
If he has sent them the before and after and the impression which hasn't been distorted at all then it is definitely crummy work at the lab. You should definitely NOT be paying for anything more than one set of crowns.
These days most dentists are using ceramic crowns with no metal on the front teeth for better aesthetics long term. If yours is still using porcelain fused to metal it's a dated treatment.