My wife's teeth look a lot like her shoes, and although I tell her to go to T.J. Maxx and buy herself a new pair (of shoes - they are about 10 years old), she's stubborn and insists they're just fine.
She is approaching 40, which means she's been chewing on her adult teeth for at least 27 years. While it might be okay to keep that old pair of comfy shoes, it's not always okay to ignore the signs of wear and tear on your teeth.
Teeth are covered with enamel; a thin, hard material that protects them from harsh temperatures, daily use, not-so-daily use, and 'habits' such as bruxism. While the body is capable of repairing broken bone, once a tooth chips, the damage is permanent.
So while we don't have to use our teeth to gnaw down trees and make dams, our teeth do take a bit of a beating over the course of a lifetime, and unfortunately they don't grow back.
Experts suggest that we should chew each bite of food a minimum of 20 times in order to aid proper digestion and prevent overeating. When we chew, force is applied in part to the food, and not just directly to the teeth. Estimates are that the forces generated during chewing food is powerful enough to crack a walnut!
All of this mastication doesn't even take into consideration the assault from gobstoppers, grinding, clenching and gnashing of teeth at your spouse/co-worker/the end of an episode of "The Walking Dead."
Bruxing & Clenching
Much like belt sanding can quickly smooth down a rough plane of wood, bruxing (aka grinding) exerts powerful forces on not only your teeth, but also to the surrounding gums and joints. Bruxing can be multi-directional, meaning either the side to side movement (left to right) or front to back of the jaw movement.
Long term bruxism obviously causes changes in the appearance of teeth and as they wear out, they can become short and stubby, and back teeth can begin to lose their cusps and natural contours.
This has a bit of a domino effect on the rest of your face, because stumpier teeth mean that when your mouth is closed, both upper and lower jaws are closer than they used to be, and therefore so are the nose and chin. Skin may even start to bag below the eyes and curl around the lips, which gives the appearance that your lips have disappeared! Let me tell you, there is nothing like a receding chin to make a person look older.
Clenching doesn't have the same side to side and/or front to back movement that bruxing does, so it tends to affect your anterior teeth more so than your molars. The problem that arises when front teeth are worn down is that your primary biting surfaces are damaged, which makes it much harder to tear into that BLT!
Typically by age 40 or 50, most bruxers have worn their teeth to the point that extensive tooth restorations are necessary. This is why mother nature evolved to make the dentist - because a lifetime of grinding and gnashing can result in a rather extensive treatment plan.
Most treatment plans involve a two pronged approach; Repair and Protect!
As you know, once you have worn the tread out on a set of car tires, they are unable to grip anything and must be replaced. Eventually, it becomes necessary to replace the entire biting surface of a worn tooth with a crown. The issue with only replacing parts of a tooth (with a composite resin aka white filling material) is that the behavior (bruxing and clenching) has not changed and will just create a new spot for opposing teeth to break it off again.
Using an artificial material which is at least as hard as the missing enamel is key. The two materials best suited for this are gold alloys and porcelain. The gold used to restore teeth ranges from 10 to 18 carat gold depending on the application. Porcelain is then used to cover the gold, because most people don't want to look like "Jaws" from the James Bond movies. I don't advise using crowns that are all-porcelain in patients with severe wear, since the porcelain is prone to breakage when it's not bonded to a gold substructure.
Now the goal is to protect your remaining natural tooth, as well as any new restorations that have been placed. A bruxism splint is made of a hard, light cured 'plastic' material that is of varied widths depending on your occlusion (how your teeth come together when you bite down). It does not just look like a formed plastic sheath that goes over your teeth (like a bleaching or 'invisible' orthodontic tray), a bruxism splint is more than just a 'pocket protector' for your mouth. While it doesn't prevent bruxism, it does redistribute the force across the masticatory system. The splint is generally only made for the upper arch and is custom built taking into consideration the placement of current teeth and wear patterns.
Your teeth really are no different than the tires on a car, or a pair of running shoes on your feet, in that they are what takes the point-of-contact, day-to-day wear and tear of eating... driving... running. Of course, putting on a new pair of shoes and going out for a jog feels a lot more satisfying than testing out a new set of dentures on a medium-well porterhouse.