Toe straighteners, toe spacers, toe braces, correct toes and toe splints come in multiple forms, materials, types and shapes. The terminology as to just what they are is also quite variable and there is certainly no standard definition of the different types and just what they are.
Some such as the bunion correctors are fairly commonly known and used. They are designed to correct the alignment of the big toe to help bunions, so are technically “toe straighteners”.
Other devices made from a silicon gel such as the toe straightener above is designed to straighten the toes, by pulling them down to the ground. Others such as these (which they call a “toe corrector”):
These are different in that they focus more on separating the toes. So while both these types could be called “toe straighteners” or “toe correctors”, they both can have differing effects and actions. Which one that should be used is going to depend on the nature of the problem and just what needs to be “corrected”.
Typically these are made of soft gel, so are soft, flexible and comfortable so can be worn in the shoes if there is sufficient room. The first thing to check is that is there is enough room in the shoe to wear them. If there is enough room in the shoe, then you need to wear them for long enough and frequently enough to correct the problem – everyone is going to be different in how they respond so it is really hard to give any blanket advice to cover everything. If the toe alignment problem is flexible, then there is going to be lot more correction a lot more quickly. If the problem is more rigid, it is going to take long to straighten the toes.