WHY DO I NEED A CROWN, WON'T A FILLING DO?
by Stephen H. Hook, DDS Westchester Los Angeles Dentist
Throughout the years in my Los Angeles Dental Practice I have been asked this question in one form or another for many reasons. What motivates the question is usually confusion--a genuine ignorance about the differences and indications between the two procedures. However, often the patient is aware that the crown is more complicated and will probably cost more as well as entail more appointment time in the dental chair. Let's discuss this topic and clear away at least some of the misconceptions and perhaps even educate in the process.
First of all in its simplest terms a filling be it metal, tooth-colored or otherwise acts as a "plug" filling a defect in a tooth. The filling is really only as robust as the remaining tooth structure that holds it in place. If you start with a large tooth that is in good condition and the defect (cavity) is relatively tiny you can place a small filling in that tooth and that restoration may persist for decades! However, if the defect is relatively large and/or if the tooth is small then the filling will not be held in place securely and is very likely to break free or worse yet the remaining natural tooth structure could easily be broken off under normal chewing function. It is a simple matter of mechanical stress for the most part.
A crown on the other hand envelopes the tooth like a hat or crown will cover your head. The crown, properly made, returns strength to the tooth and permits full chewing function over a long period time--perhaps decades. A weak tooth is protected by the crown whereas the filling requires a strong tooth to hold it in place. This is the difference between the two terms in its simplest terms.
I have found that several considerations enter into a patient's mind when choosing between fillings and crowns. What is important for one person might be quite different for another. The concerns raised seem to fall into these basic categories: cost, longevity, comfort, time and aesthetics. Usually the most important consideration wins out over the other four.
Cost would seem to be the easiest to understand and discuss, but we are all familiar with how our budget ideas will change with desire. Generally we spend money on what we want and not just what we need. If convinced that an increased cost will gain you better value for your investment then you will likely pay more for an item or a service and be satisfied. Crowns are more expensive than a filling by sometimes as much as 8--10 times! Crowns require more time to make. Crowns require a laboratory to fabricate it and that cost figures into the final price. However a crown usually functions much better than a large filling, will stand the test of time and although it takes longer to place a crown than a filling the time is ultimately much less than the time spent replacing the filling several times over the years. So if cost is the most important consideration for a patient, they still may decide to spend more for the perceived value.
Longevity is a factor that is predictable to some degree, but again poor home care and careless habits can threaten the service life of fillings and crowns alike. All things being equal, a well-made crown will outlast a large filling every time. Eliminating destructive habits such as chewing on ice, using your teeth as a tool to open packages, clenching and grinding your teeth and engaging in contact sports without a mouth guard will insure longevity for your dental restorations both fillings and crowns. Good oral hygiene--brushing and flossing--is essential to preventing failure of crowns and fillings from new decay. Only implant-supported crowns will not decay; all others need to cleansed well daily.
Comfort should objectively be due to a painless and restful experience during the dental appointment, but most of us know better. Anxiety and restlessness work against us when having any dental procedure done. Dr./Patient trust is all-important for comfort. If the doctor and the patient are mutually agreed on a single, best course of action then it's easier to relax for both the doctor and the patient and comfort is improved. After the treatment there may be tenderness for awhile but residual sensitivity and soreness from large fillings is far more likely than with a crown. Dispelling fear and understanding through trust works well to create comfortable dental care.
Time is always an issue but I have found that how I see time is highly variable depending on my disposition and outlook. When I was in dental school a favorite saying was: "There's never enough time to do it right, but always enough time to do it over!" I eventually found out that to do excellent treatment I had to work carefully and purposefully and I could not do it well if I felt rushed. Most patients would like to spend less time in the dental chair and fillings usually are less time-consuming to complete than a crown. However, the vast majority of patients I have worked with have recognized the wisdom of doing the right treatment even if it takes more time because "doing it over" a short time later when the filling breaks is really a waste of valuable time.
Aesthetics or beautiful restorations are very important for most people and often this is the value that trumps all the other ones including cost. No one wants unsightly holes or ugly fillings in their mouth. Almost universally dental patients in Los Angeles will decline silver or gold fillings or gold crowns. It must be tooth-colored for patients to be happy. A problem arises when the demand for natural-colored fillings and crowns is so absolute that logical superior alternatives are not even considered. Many times crowns and fillings in the very back of the mouth are not visible to anyone but the dentist and these teeth undergo some of the heaviest bite pressures of any of the teeth. Here strength is extremely valuable and most tooth-colored fillings and crowns are weaker than silver and gold ones. Does it make sense to pay extra for aesthetic tooth-colored restorations that can't be seen and sacrifice functional strength which may increase longevity? I must defer to the patient's judgment if possible but sometimes I am unable to do so. Once a patient insisted on a tooth-colored root canal filling that is entirely encased inside the tooth and cannot be seen at all except on x-ray. There was no acceptable tooth colored filling material available so I had to decline to treat the patient.
In summation, the choice between a filling and a crown has to ultimately be made by the patient. The values that patients have determine their choices. Whether they value cost, comfort, longevity, time or aesthetics what is most important, what the patient wants is what we dentists try to serve. As a matter of integrity and honesty on occasion I have declined to treat a patient because I could not support their request. In most cases there is one best way to restore a tooth that a majority of dentists and patients would select. Insurance company policy, budgetary necessity, and overwhelming family/personal bias don't always allow for a patient to embrace the obvious best choice. In this case the Dr./Patient trust factor being strong enough usually allows a satisfactory treatment result.