The teeth are supported in the bone by a thin layer of tissue called the periodontal ligament. When your filling is too high, the teeth will be pressed even harder, which makes the ligaments very soft.
All the tissues of our body become soft when stressed. For example, if you work outside the garden all day, and you pull your gloves off without gloves, your hands will turn red and become inflamed. Therefore, the body will deliver extra blood to your hands to help them heal. As part of the healing process, they become red, inflamed and very soft. This is the case of periodontal ligament development when it is subjected to more compression than normal due to high filling.
