When the gums recede, the causes can be different. Always check with a specialist visit. They may be due to periodontal disease and are therefore difficult to correct, but they may be due to orthodontic treatments that have moved the teeth out of their position in the bone, or due to incorrect brushing or a thin gum.
The exposed root can feel the heat and cold more, it can decay, or it can ruin a smile.
There are dedicated surgical techniques that can correct the defect. The Doctor will advise you on the best one for your case.