Bunions are an enlargement of the great toe or hallux joint of the foot and are frequently related to what is known as hallux valgus that is a deviation of the great toe or hallux towards the outside. They may or may not be painful, but the possibility of them to be painful is high. For that reason prevention and treatment is usually typically indicated. They do tend to be progressive to get worse with time. The only real way to get rid of bunions is with surgery, but that's not necessarily a good solution in the beginning. One way in which they may be treated is by using what is called bunion correctors, however they are often coupled with the question, would they work? They are splints or braces used at night in an attempt to correct the deviation of big toe to improve its look.
A great deal is determined by what is understood by “working”. There's a lot of thoughts and opinions as to them both working and not working with minimal scientific evidence. There's one published study that did reveal that the angle of the great toe will be improved by a few degrees after one months use, but this wasn't research of any more than that one month. Thus, yes, it does seem that bunion correctors can work in the short term at improving the angle of the hallux valgus or bunion a few degrees.
Aside from that piece of research all we can rely on is expert opinion. Most of that opinion is in line with that research study. Nevertheless, it also appears that even if the use of the bunion corrector doesn't improve the angle of the great toe or just helps it a tiny amount, it can be entirely possible that the corrector can go a long way to preventing the problem from becoming worse. That is significant as bunions are progressive. The splint may also be very helpful at stretching out the ligaments surrounding the joint which can be helpful with pain inside the joint.