Hello, The gap looks bigger than
before treatment is normal. If Is less space it will get close by itself slowly. If triangular space Is more it will not get close but after treatment you have maintain with proper oral hygiene measures like brushing twice after every meal clan it if space is big use interdental tooth brush
If tooth is vetting displaced and more mobility, immediately after treatment means it will reduce gradually if it persists for long then get it checked if possible visit periodontist
he will guide You. He is specialist for gums.