Sapphire and ceramic braces are made of a material that is very hard but brittle, which makes them more prone to breaking than metal braces. Aesthetic braces are bonded to the front surfaces of the teeth, which aren't exposed to much pressure during chewing, especially if the patient follows the advice to avoid hard foods. I can say that, although they are more brittle, aesthetic braces rarely break in the mouth. It's more common for them to come loose under the pressure of food, but how firmly a bracket stays on is determined mainly by the bracket adhesive. This means that metal and aesthetic braces are bonded to the tooth comparably firmly. Even so, it's fair to say that aesthetic braces come loose more easily, and the reason is their size – the bracket is larger, so it's easier for it to be pressed on and knocked off.
This answer is for general information. Your own case needs an examination by an orthodontist.