QC- User Field - Regular Expression

Is there a way to apply a Regular Expression to User Field as Input Mask?

I want to create an input mask for builds:

for example '3.15.3.234'

The patter should be: 3digits.3digits.3digits.4digits

I tried to do this on the Input Mask : !990.099.099.0999 but, once it's running the variable looks like ' 3.7 .8 .123' it keeps the 'blank spaces'.