People born without teeth, a condition called Ectodermal dysplasia never form jaw bone called the alveolus. The reason is that it is the tooth that causes the formation of and the retention of the alveolar bone, so when a tooth is lost, the bone begins a never ending process of melting away. The one and only way to stop bone loss after tooth loss is to stimulate the bone with an implant.
Bone loss makes dentures more and more unstable and increasingly painful. Diets change to that which can be eaten rather than that which is desired and healthful, creating systemic illnesses, more and more medications to treat symptoms and shortened life spans. Sadly, many patients only seek implant treatment after significant bone loss which limits treatments or creates the need for greater and greater investments in bone grafting to recreate that which has been lost.
Tooth loss reduces bite forces many times which causes the facial muscles to wither away and detach from facial bones. As bone continues to melt, the chin gets closer to the nose causing an aged look. The good news is that with implants, bite forces are actually higher than with teeth so muscles reattach and new correctly made tooth replacements can restore proper facial height creating dramatic life changing transformations.