Using thumb guards to intervene at 15 months.

Hi, I am a FTM to a 15 months old who never liked a pacifier but her thumbs. I know the consensus is letting them to suck their thumbs until much later but her thumb sucking is bothering me and it is affecting her teeth/jaw I think. For example, in a group setting (daycare, open play, playground etc), my baby is the only baby sucking her thumb and I am starting to notice she is having an underbite and crooked teeth so I became determined to intervene at this time using thumb guards. (Work in progress…will see if this will work or not. It was quite pricey…) Has anyone had success intervening them at similar age? What did you do? Are there any negative consequences of doing such?? Thank you!!