Our molar teeth are often the first adult teeth in our mouths, and they are subject to tons of wear and tear over time. For many patients, these are the first (and sometimes only) teeth to have cavities and fillings, and over time, they break down. The fillings get bigger, the tooth gets weaker, and the nerve of the tooth is affected. Root canal treatment is the removal of the nerve from inside the tooth roots, and in some cases this treatment is the only way to save the tooth. Once a root canal is done, the weakened tooth is best rebuilt with a tooth crown to brace the tooth and hold it together.

Is root canal-and-crown a “forever” treatment? I wish I could say this is true, but in many cases the tooth can still fail. Oftentimes, the faulty environment that caused the first cavity still exists. Cavities are caused by bacteria and dietary sugars creating decay and breakdown within the tooth.

This can be avoided altogether with excellent oral hygiene habits and diet from a young age, but some of us start our history of decaying teeth early. Once those cavities are cleaned up and properly sealed, our teeth are still living in the same environment that caused the decay in the first place, so unless we make significant changes to our diet, our homecare, and sometimes even more concentrated efforts at bacterial control, cavities will occur again. It’s a tough but unfortunately predictable cycle.

Another factor in predictable dental work is the way your teeth bite together. In an ideal case, the teeth in the top jaw fit together with a slight overlap the teeth in the bottom jaw (think of how a box top fits over a box bottom), with all teeth straight and no gaps. With this scenario, the forces of eating and swallowing placed upon our teeth will be well-balanced, and will not negatively affect our teeth or any dental work. However, as in the case of the photo above (left), the top teeth bite down on the inside of the bottom teeth, making the bite force affect the teeth poorly.

In the photo on the right, I’ve drawn several arrows pointing to a crack in the root of the tooth, a result of such unequal biting forces. Since the bite is out of whack, it has also caused the crown on the tooth to the right to come away from the tooth, allowing bacteria to get in and cause a cavity. The larger molar tooth in the photograph will have to be removed and replaced with a dental implant, and while the smaller tooth may be able to have a new crown, this may not be a predictable and long-lasting treatment, as long as the bite remains poor.

Adult patients often think they cannot have braces to correct a bad bite, but this is simply not true. I’ve worked with patients well into their 70’s having orthodontic correction of crowded and tipped teeth to improve the function and longevity of their teeth! The lovely side effect to having a balanced bite can also be a nicer smile, and who doesn’t want that?

Modern dentistry offers us a variety of ways to repair and replace what isn’t working in our mouths, and the science behind this continues to improve. In the end, the best defense against dental problems requiring procedures such as a root canal is excellent homecare, a healthy diet, and a strong, solid bite.