Molars: The Choice of Crowns and Bridges Vs. Large Fillings
Everyone that's had any dental work done, even in this "modern" age, needs to know some thing- that nothing is 100 percent or lasts forever. Anytime the dentist goes into a tooth and takes away decayed tooth structure, the tooth is weakened as a whole. When the treatment options are given to you as the patient and the choices are a large amalgam (silver)/composite (tooth-colored) filling and many pins or a crown (cap)- the response you give is 50/50. Half of you will choose the "cheaper" route and want the cheaper amalgam/composite and the other half will choose to crown or cap the tooth. The choice that is made can have a serious affect on that tooth, and possibly others, from that day forward.
Let's view the two choices. The first choice, the "cheaper" of the two, calls for a restoration that sits inside the walls of the remaining tooth structure. These walls are usually very thin due to the amount of decayed tooth structure that was taken away and this filling could act like a wedge that is being driven downward/upward against the weakened tooth structure. The results usually are a cracked wall or complete fractured wall. If there are no walls remaining, then retaining that filling will be very difficult to do no matter what restorative material the dentist uses and small pins may be placed inside the tooth to help anchor or retain that filling in place. What people should know is that to place these pins into their correct position, small holes into the dentin or middle layer of the tooth are drilled and then the pins are screwed into place. These pins are sometimes very close to the pulp or live part of the tooth (the nerve) and when irritated sometimes develops an irreversible inflammation that would cause a small infection of the tooth and a root canal or extraction would be needed to take care of this infection. If more than one pin is placed, which is common practice, then many "weak spots" now exist in the middle layer of the remaining tooth structure. The chances of one of these many pins causing an irritation to the nerve and resulting in an inflammatory or swelling of the nerve increases with the number of pins placed to hold this large filling in its proper place. Now the patient and dentist have to worry about the strength of the middle part of the tooth - is it going to be strong enough to withstand the pressures put upon it from eating? Will the patient be calling in a week, a month, or a year because all of a sudden that tooth is starting to be cold sensitive, throbbing at night? "The tooth never bothered me before you put that filling in but now it's killing me!" I hear this all the time in my own practice.
This tooth, which has few if not any walls remaining now, has several anchors holding a large filling in place and is expected to endure most of the forces of chewing food, some of which consist of hard popcorn kernels, raw veggies, chewy meat, and croutons. These foods require a lot of chewing power from the jaw muscles to break them down. Unfortunately, most of the time, this arrangement doesn't last for more than a short amount of time and the patient comes in with a tooth that is fractured and more often than not, is fractured vertically down the roots and will need to be extracted. What did the patient gain from the large filling-many-pins procedure not too long before? Borrowed time, maybe?
Now the patient needs to have the remaining tooth extracted due to its unrestorability and a hole remains. What can you do for this hole? There are several options here, depending on the remaining bone level from the extracted tooth, what shape the rest of the remaining teeth are in, and the time and budget constraints the patient has. The patient can opt for a removable partial denture ($600-$1,200) they can replace the missing tooth; an implant ($1,200-2000 + cost of a crown), which is a titanium screw that is placed in the jaw bone and literally becomes "the missing tooth"; or a 3 unit bridge ($1,500-$3,000), which caps or crowns the tooth in front of the hole, the hole is filled with a pontic or crown, and the tooth behind the hole is crowned so that all three teeth are linked together like a road bridge. The last alternative is not to do anything with the knowledge that teeth are alive move, drift, and shift, especially if there's not another tooth beside it to keep it in place.
Can we then conclude that you get what you pay for? If the patient would have chosen to crown or cap this very weak tooth, the probability of success for many years to come increases dramatically. Even the patient that loses the tooth and opts for a 3-unit bridge or implant helps to maintain the configuration of the mouth and can help strengthen his/her bite. The dentist would still have to build this tooth back up, but could then make a ledge for the crown to sit on, which would surround the remaining tooth and build-up structure, and would protect it from the forces of everyday chewing. The crown ($500-$1,000) could be made of all porcelain, not the strongest material for posterior or back teeth but highly esthetic or natural-looking; porcelain and metal - most dentists' choice for these teeth due to the strength of the metal, which is covered by the esthetic or natural-looking porcelain (the best of both worlds); or the all gold - the older generation's choice of material. The durability of gold is outstanding but the esthetics or look of them are not the most desirable for some people. The prices for these procedures differ depending on where you live, but most insurance will cover at least 50% of these procedures. If you spend a little more now, it will save you a lot of time and money down the road.