To notice your gums in your dream suggests that you are having difficulties communicating your emotions or thoughts. If your gums are sore, then it means that you have been holding back those negative emotions and thoughts for too long. You need to let go and start expressing your emotions.
To dream that your gums are bleeding indicates that you feel others are working against you.
To dream that a thick, gray discharge is oozing out of your gums implies that you need to confront some fear or depression. You have been trying to avoid these feelings.