- I. The initial crown appointment.
- II. Your second crown appointment.
- III. What precautions should be taken with a temporary crown?
- IV. What to do if a temporary crown comes off?
- V. Pain and discomfort while your temporary is in place.
- VI. What problems might be experienced with a permanent crown?
- VII. What type of crown should you have made?
- VIII. How long do crowns last?
Before and after with Crowns can be Dramatic:
I. The initial crown appointment.
A. We will numb your tooth.
Before the process of making your crown is begun us will anesthetize (numb) your tooth and the gum tissue which lies around it.
B. We will shape your tooth.
So a crown has adequate strength and, in the case of porcelain type crowns, proper aesthetics, a crown must possess a certain minimal thickness. Your tooth in turn must be reduced by this same amount so once the crown is cemented into place your tooth will not be oversized. The minimal crown thickness that is usually needed lies on the order of about two millimeters or so, which is just a little more than a sixteenth of an inch. Usually, 60% of the tooths outer surface or more needs to be removed.
In those areas where a portion of your tooth has already broken off I may find that they have very little tooth reduction to accomplish. As a part of the trimming process us will ensure that any and all decay has been removed from your tooth.
Besides reducing your tooth so it is smaller in size us must also shape your tooth in a specific fashion. A tooth receiving a crown must be slightly tapered in form so the crown will slip over and seat on the tooth.
The more tooth structure that extends up into the interior of a crown the more stable the crown will be. There can be times when so much of a tooth has broken off that a dentist will feel that they must first "build up" a tooth with filling material (make the tooth taller) before they do the final shaping for the crown. (See Top Menu)
C. We will make an impression of your tooth.
Once your tooth has been shaped appropriately us will need to make a copy of it (termed taking an "impression"). Your crown then in turn will be made from this impression. There are two scenarios by which this process can occur:
1) Most dentists will take an impression by way of making a dental mold of your tooth using impression paste (a putty like material). This impression will then be sent to a dental laboratory that will in turn use it to create a plaster cast of your teeth. A dental technician will fabricate your crown so it fits accurately on the plaster cast. Since the cast is a precise representation of your teeth the crown will fit on your tooth also. Depending on the arrangements us have made with the dental technician, the amount of time required to fabricate a crown is usually lies on the order of two useks or so.
2) Some dentists might have a dental milling machine in their office. These machines are attached to a camera that can take an impression of your tooth optically. From this image the machine can subsequently design your crown and then create it by grinding down a block of dental ceramic ("porcelain"), all in a matter of some minutes. The obvious advantage of this technique is that a tooth can be shaped and its crown cemented into place, all in one visit. Our office does not utilize a milling machine good reason. Milling machines can only be used to fabricate all ceramic ("porcelain") crowns and the fit, physical properties and the aesthetics of this type of crown are not acceptable to us. (See Top Menu)
D. A temporary crown will be made for your tooth.
The crown will be created by a dental laboratory and you will have to wait the two to three useks while your crown is being fabricated. During this time period your tooth will be covered over by a temporary crown that we have made. The temporary crown, which is typically made from plastic or else a thin shell of metal, will be cemented into place over your tooth. (Information regarding temporary crowns.)
E. We will select the proper shade of porcelain needed for your crown.
If your crown will have a porcelain surface we will need to determine what shade of porcelain most closely matches your tooth's neighboring teeth. Usually a dentist will have a series of small tooth shaped pieces of dental porcelain (each of a different color) which are collectively called a "shade guide". We will select various porcelain samples from the shade guide and hold them in the area your new crown will occupy, until they find the one which most closely matches the color of your tooth's neighboring teeth. (See Top Menu)
II. Your second crown appointment.
Cementing your permanent crown in place.
At that point in time when the fabrication of your crown has been completed we will proceed with the process of cementing it on your tooth. We will first make sure your tooth is numb. Then, if a temporary crown has been placed we will remove it.
Before we can cement your new crown into place they will first need to evaluate the way it fits on your tooth. To do so, we will place the crown on your tooth, inspect its fit (possibly by way of using dental floss, feeling it with a dental tool, or asking you to gently bite down), remove the crown and adjust it, repeatedly, until they are satisfied.
Especially in those cases where the crown will hold a prominent position in your smile, we will also evaluate (and probably ask your opinion about) the crown's overall shape and color.
Once you and I both agree that all seems right with your new crown it can be cemented. We will first place dental cement inside your crown and then seat it over your tooth. After a few moments we will use a dental tool and scrape away any excess cement that has extruded from underneath the edges of your crown. The placement of the crown is now complete. (See Top Menu)
III. Precautions with a temporary crown
Here are some things to know about temporary crowns, including some of the types of precautions dentists often recommend their patients take during that time when their temporary crown is in place.
Temporary crowns are held in place by "temporary" cement.
Temporary crowns are usually cemented into place using "temporary" cement so they can be removed easily at the time of your next dental appointment. Because this cement is not as strong as other types of dental cement, we will probably suggest that you take some precautions so not to dislodge your temporary crown. Some of the types of precautions we might suggest are listed below. You will simply need to ask us if any of these precautions (or any other precautions not listed here) are important and relevant to your specific situation.
- Minimize the usage of the side that has the temporary crown.
- There's no need to look for trouble, give the temporary crown some consideration when eating. As much as possible, shift the bulk of your chewing activities to other areas.
- Keep sticky foods away from the temporary crown.
- Anything sticky (caramel, chewing gum, etc...) has the potential to grab onto the temporary crown and pull it off its tooth.
- Avoid chewing hard foods with the temporary crown.
- Chewing exceptionally hard foods, such as raw vegetables (carrots), can dislodge or break a temporary crown.
Suggestions related to brushing and flossing a temporary crown.
A tooth with a temporary crown can usually be brushed and flossed in normal fashion, with the following consideration. After flossing it may be best to remove the dental floss by way of letting go of one end and then pulling it out to the side. Pulling the floss back out in normal fashion might snag the temporary crown and pull it off its tooth. (See Top Menu)
IV. What to do if a temporary crown comes off?
If your temporary crown does happen to come off contact our office so they can provide you with specific instructions and also make arrangements for you to come in and have it recemented. (See Top Menu)
In regards to that time period before you get back to our office to have the temporary crown recemented, we might suggest that you simply place the temporary crown right back on your tooth. Doing so can protect the tooth somewhat from irritating stimuli such as hot or cold liquids. Wearing the temporary crown will also hold the tooth in place and keep it from shifting position (an important factor in how well or how easily your permanent crown can be fitted). Report to us if you have found that the bite on your temporary crown seems incorrect when it is placed back on your tooth. In this situation we will probably prefer that you leave the temporary crown off.
If your uncemented temporary crown doesn't seem to stay in place very well we might suggest that you fill it with toothpaste, vaseline, or else denture adhesive before you place it over your tooth (this technique should only be used for a few days). Of course we will no doubt advise you that you will need to be careful with your temporary crown until it can be recemented. So you don't end up swallowing or biting on it unexpectedly, we will probably state that your temporary crown should be removed when you sleep and eat. Anytime your temporary crown is not in your mouth you should keep it wet. Put it in a glass of water or close it up in a baggie containing a moist paper towel. (See Top Menu)
V. Pain/discomfort with your temporary.
If you notice any pain or discomfort with your tooth it's best that you let us know so they can evaluate your symptoms. Here are some of the types of problems that can occur:
A. The tooth has increased thermal sensitivity.
It is fairly common that a person will notice some increased sensitivity to both hot and cold foods and beverages during that time during which their temporary crown is in place. This can often be related to the fact that the edges of the temporary crown cover over the tooth less fully and precisely than a permanent crown's edges will, thus providing a space by the gum line where these thermal irritants can get at your tooth. Just to play it safe however, in this situation go ahead and contact our office, report your symptoms, and let them make a determination. (See Top Menu)
B. The gums around your tooth hurt.
It's not unusual that the gums around a tooth that has been prepared for a crown will be tender for a day or so. Since the edge of most crowns end at or below the gum line which requires us to place a piece of cord (string) to exposure the margin of the tooth to perform dental work in this area. It is very easy for a person's gums to get brused during the crown making process. As a solution a dentist will often suggest that rinsing with warm salt water up to three times a day may speed up the healing of this gum tissue. However, in all cases, if something seems amiss you should feel free to report to us and let them evaluate your situation. (See Top Menu)
C. The bite on your temporary crown seems incorrect.
After your numbness wears off you may find that when you bite down your temporary crown touches first or hits harder than its neighboring teeth. In these instances we will probably be very eager to adjust your temporary crown so your bite is more even. Don't expect this situation to take care of itself or improve with time. Allowing this condition to persist can seriously aggravate the tooth's nerve or even compromise its health. (See Top Menu)
D. Discomfort with your tooth.
It is not out of the ordinary that a tooth might feel a little aggravated after having been drilled on. If you do notice discomfort go ahead and let us know so they can evaluate your symptoms. As a solution for minor reversible conditions, a dentist will often suggest that their patients take an anti-inflammatory analgesic (such as ibuprofen or aspirin) so to help their tooth settle down. (You will need to read and evaluate the directions and precautions that accompany these products so that you know that their usage is appropriate for you.) (See Top Menu)
VI. Possible problems with a permanent crown?
People can and do experience problems with those teeth on which a dental crown has been placed. No doubt it is both your and our hope that once your crown has been completed that your tooth will be just fine. Unfortunately, life sometimes runs contrary to our wishes.
Here are some of the types of complications people can experience, they can range from very minor and common place in nature to serious and disappointing. In all cases, if you experience a problem you should let us know, sooner rather than later, so they can evaluate your symptoms and make a treatment recommendation.
A. The tooth has sensitivity to both hot and cold stimuli.
It's not uncommon that, after a crown has been cemented into place, a person will notice that their tooth has sensitivity to both hot and cold foods and beverages. Typically the location of this sensitivity is at the edge of the crown, by the gum line.
In some cases a dentist might have a very simple solution for this problem. The solution might be as easy as using a tube of one of those toothpastes marketed as being a treatment for "sensitive teeth" (the active ingredient in these products is usually potassium nitrate). However, rather than make an incorrect treatment decision yourself, let us know you are having a problem so they can evaluate your situation and make a recommendation.
B. The bite of the crown seems off.
We will have evaluated the way your crown touches against your other teeth when you bite down during that visit when they cemented your crown in place. Even so, you may find, especially after your numbness has worn off, that some aspect of your crown's shape is not quite right. Possibly when you bite down you feel your crowned tooth makes contact first, or maybe as you slide your teeth from side to side you can feel some aspect of the crown which seems too prominent.
This type of problem is usually an easy fix for us, they simply need to buff your crown down so its shape is more in harmony with your bite. Don't expect this type of problem to take care of itself because it won't. In fact, if this condition is not remedied promptly it can lead to serious consequences related to the health of the nerve in your tooth. (See Top Menu)
C. Other difficulties with crowns.
The same events and circumstances that have led to the need for your crown (a broken or cracked tooth, a large cavity, etc...) can have a detrimental effect on other aspects of your tooth's health. Possibly your tooth was asymptomatic initially and now that the crowning process has been begun (or completed) problems seem to have popped up. While this set of circumstances is disappointing, it is not an indication that all was well with your tooth initially. It simply suggests that the full extent of the tooth's problems could not be identified beforehand.
Sometimes after crown treatment has been begun or completed a problem with the tooth's nerve becomes apparent and subsequently root canal treatment is needed. Some teeth are cracked seriously enough that even a crown cannot hold the tooth together sufficiently. These are not circumstances we can predict with certainty, they can't see the future and know all outcomes. We are simply trying to rebuild your tooth in that fashion that their experience and training suggests to them is best and most reasonable.
If you have found that a problem has developed, or has persisted, after your crown has been placed simply report to us, sooner rather than later, so they can evaluate your current situation and suggest a treatment solution. (See Top Menu)
D. What to do if a crown comes off.
If your crown comes off let our office know promptly so they can provide you with specific instructions and make an appointment for you where they will evaluate your situation and then, if possible (and it very often is), recement the crown on your tooth.
During that time which exists before your dental appointment we may suggest that you simply place the crown back on your tooth. The idea here is that wearing the crown will protect your tooth from irritating stimuli such as hot or cold liquids. Placing the crown on your tooth will also keep the tooth from shifting. (A tooth without its crown can shift in position so much that a dentist will not be able to recement the crown but instead will have to make you a new one.)
Sometimes when a person places a dislodged crown back on their tooth they will find that the crown's bite seems to be off. This condition must be reported to their dentist so a revised recommendation can be made. Usually in this instance a dentist will feel that is best just to leave the crown off, but that is for them to decide.
If your crown doesn't seem to stay in place very well we might suggest that you fill it with toothpaste, vaseline, or else denture adhesive before you place it over your tooth (this technique should only be used for a few days). Of course we will probably also tell you you will need to be careful with your crown until it can be recemented. So you don't end up swallowing or biting on your crown unexpectedly, we will probably suggest that you remove your temporary crown when you sleep and eat. (See Top Menu)
VII. What type of crown should you have?
Crowns can be made from metal, ceramic materials (porcelain), or a combination of both. The information on this page discusses the pros and cons of each of these various types of crowns, but in general you should rely on our judgment and advice as to which of these types of crowns would be most appropriate for your situation.
All metal crowns / Gold crowns.
Some crowns are made entirely of metal. The classic metal crown is one made of gold, or more precisely gold alloy. Over the decades a variety of different metal alloys have been put to use in making crowns. Some of these metals are silver in color rather than yellow like gold.
Having a gold crown made can be an excellent choice. Here are some reasons why:
- Because of its physical characteristics dentists find gold to be a very workable metal and one which lends itself to their being able to achieve a very precise crown fit.
- Since they are metal through and through, gold crowns withstand biting and chewing forces well. They will not chip. It would be uncharacteristic for a gold crown to break. Of all of the types of crowns, gold crowns probably have the greatest potential for lasting the longest.
- Although they are very strong the wear rate of a gold crown is about the same as a person's own tooth enamel. This means that a gold crown won't promote excessive wearing of the teeth it opposes (the teeth with which it bites against).
Metal crowns are usually placed on those teeth that are not overly visible when a person smiles (i.e. molars). If you are considering having a gold crown made take our advice on this point. Before you give us the go ahead on making a gold crown, check with your spouse first. They're the one who will be looking at your smile and your new crown the most.
crowns that will show prominently when you smile are usually either made of porcelain or else have a veneer of porcelain on their surface, so that the crown's color is white like the rest of your teeth. (See Top Menu)
All porcelain crowns.
Some crowns are constructed in a manner where their full thickness is porcelain (or some other ceramic material). These crowns can possess a translucency that makes them the most cosmetically pleasing of all of the different types of crowns.
Although they can be very life like in appearance, the overall strength of all porcelain crowns is less than the other types of crowns. While they can be a good choice for front teeth, due to the large chewing and biting forces which humans can generate an all porcelain crown may not be the best choice for back teeth.
Porcelain fused to metal crowns.
Porcelain fused to metal crowns are somewhat of a hybrid between all metal crowns and all porcelain crowns. When they are made the dental technician first makes a shell of metal that fits precisely over the tooth. A veneer of porcelain is then fused over this metal, giving the crown a white tooth-like appearance. Depending on the requirements of your situation, these crowns are sometimes made where the porcelain veneer only covers those aspects of the crown that are readily visible (the other portions of the crown have a metal surface), in other cases these crowns are pretty much fully surfaced by porcelain.
Porcelain fused to metal crowns can be a good choice for either front or back teeth. These crowns are strong enough to withstand heavy biting pressures and at the same time can have an excellent cosmetic appearance. There are some disadvantages associated with porcelain fused to metal crowns however (which no doubt we will try to minimize as much as is possible). They are:
- While the cosmetic appearance of these crowns can be excellent, they often are not as pleasing aesthetically as all porcelain crowns.
- The crown's porcelain can chip or break off.
- The porcelain surface of the crown can significantly wear those teeth that bite against it.
- The metal underlying the crown's porcelain can sometimes be visualized as a dark line found right at the crown's edge. A dentist will usually try to position this dark edge just underneath the tooth's gum line but if a person's gums recede this dark line can show, thus spoiling the crown's appearance. (See Top Menu)
VIII. How long do crowns last?
It would be reasonable to expect that a crown could last between five and fifteen years. Most likely a crown which did only last five years would be somewhat of a disappointment to us. It's probably their hope that any crown they make for you will last ten years or longer. Depending on what wear and tear the crown is exposed to, and how well you keep the tooth free of plaque at the margins (where the crown and tooth meet), it is reaonable to see a crown last indefinitely.
Why do crowns need to be replaced?
There can be a variety of reasons why a crown might need to be replaced. Some of them are:
A. The formation of tooth decay.
While a crown cannot decay, the tooth on which the crown is cemented certainly can. If dental plaque is allowed to accumulate on a tooth in the region where the crown and tooth meet, a cavity can start.
While there can be a lot of variables with this type of situation, the worst case scenario for your crown is that in order for us to be able to get at the decay, and subsequently restore your tooth properly, the crown will need to be removed and replaced with a new one. (See Top Menu)
B. The crown becomes excessively worn.Dental restorations are not necessarily more wear resistant than your own natural teeth, nor is it in your best interest that they should be. The ideal crown would be one made out of a material which has the same wear characteristics as your own teeth. This way neither the crown nor your teeth would wear each other excessively.
Crowns can wear out, especially in those cases where a person clenches and grinds their teeth excessively. A dentist will sometimes detect a small hole on the chewing surface of a crown in that area where it makes contact with an opposing tooth (meaning a tooth which touches on the crown when you bite). In these cases, since the crown is no longer sealed to your tooth plaque can get under the crown start a cavity. Sometimes these can be treated with a filing and for a short time until the crown needs to be remade. (See Top Menu)
C. The crown has broken.
Crowns can break, or more precisely the porcelain component of a crown can fracture. Some crowns are made in a fashion where their full thickness is porcelain. In these cases if the crown breaks it will most likely break through and through. Even if the broken piece of the crown doesn't come off either the esthetics, function, or the seal of the crown will most likely have been compromised and the crown will need to be replaced.
Other ceramic crowns are of the "porcelain fused to metal" variety. When this type of crown is fabricated the dental technician first makes a thin metal shell that fully covers over the tooth, a layer of porcelain is then fused to this metal so to give the crown a tooth-like color. In cases where this type of crown has broken it is the layer of porcelain that has fractured off, usually revealing the metal tooth covering underneath (which is often grey in appearance). While the function and esthetics of the crown may have been compromised, the crown's seal over the tooth may not have been affected.
Since the seriousness of a crown fracture can vary greatly, any crown which has broken should be evaluated by us. Some minor damage might not be of much concern, and possibly ameliorated by a little smoothing with a dental drill, but only us should determine this and only after they have had an opportunity to examine your precise situation. (See Top Menu)
D. The esthetics of the crown have become objectionable.
Some crowns are replaced because, from a cosmetic standpoint, their appearance is no longer pleasing. Two situations where the cosmetic aspects of a crown can change with time are:
1) The crown's edge has become visible.
Often as time passes the gum line of a tooth on which a crown has been placed will recede. This is especially likely in those cases where diligent brushing and flossing have not been practiced. If enough recession occurs the edge of the crown, which was originally tucked out of sight just under the gum line, will become visible.
Inherent to porcelain fused to metal crowns (related to their construction) is the fact that the very edge of these crowns will show some darkness (a hint of the metal that lies underneath the porcelain). If enough gum recession occurs this dark edge will become visible, thus spoiling the cosmetic appearance of the crown.
All porcelain crowns do not have the same inherent edge darkness as porcelain fused to metal crowns. Gum recession can, housver, expose the portion of the tooth that lies beyond the edge of the crown (the tooth's root surface). Usually the color of this part of the tooth is significantly darker than the color of the crown, thus spoiling the cosmetic appearance of the tooth.
2) The color of the crown no longer matches its neighboring teeth.
Also related to the cosmetic appearance of a crown, there can be times when, as years have elapsed, the color of the crown no longer closely matches the shade of its neighboring teeth. In these cases it is not the color of the porcelain used to make the crown that has changed but instead the neighboring teeth have stained and darkened.
There can be two solutions to this situation. The crown can be replaced with a new one that more closely matches the current color of its neighboring teeth. Another solution might be to use a teeth whitening process to return the neighboring teeth closer to the color they usre when the crown was originally placed.