Implants, Crowns, and Bridges vs. Natural Teeth

Nothing can replace the natural teeth you were born with for chewing and function. However, very few people go through life without having teeth filled, crowns (caps) placed, or bridges and implants used to replace missing teeth. Crowns, bridges, and implants are the best answer and closest to your natural teeth, but they are not the same as healthy, natural teeth.

Crowns

Crowns are used to reconstruct a single tooth broken down by dental decay. Crowns are made of ceramic, resin, porcelain, porcelain plus metal, or resin plus metal materials. They are bonded or cemented onto the prepared tooth and cannot easily be removed from the tooth once placed. If the tooth was in good alignment before the crown was prepared, the crown will be in good alignment. If the tooth was misaligned before the crown, sometimes the crown may be made to obtain a more ideal shape and position. It is cleaned and flossed just like a natural tooth and is most like real teeth.

Bridges

Bridges are crowns that are attached together, suspending the crown portion of a false tooth in or over the space left by the missing tooth. A bridge can be used to replace one or several teeth. Sometimes a bridge is used to splint loose teeth together in order to make the teeth more stable. Bridges are usually made of metal covered with either porcelain or resin. Some of the newer bridges are made of all resin or all ceramic materials. They are cemented or bonded onto the existing prepared teeth and are not easily removed once placed. The bridge teeth can be brushed the same as natural teeth, but since they are attached together, must be flossed differently by using a floss threader or other device.

The teeth are generally the same shape as natural teeth. However, if the existing teeth (abutments) that are used to anchor the bridge have moved from their original position because a tooth or teeth have been missing for years, the added tooth (pontic) may be longer or shorter than the tooth that it is replacing. With a bridge, the false tooth will most often butt up against the soft tissue ridge where the removed tooth was.

The shape of the tongue side of the false tooth varies. It is usually smaller on the tongue side and completely fills the space. Food will have more of a tendency to collect in this area, so you must be prepared to clean it. If the missing tooth has been gone a long time, the ridge may have shrunk considerably, and the pontic tooth will be longer that the teeth on either side. If this is the case, there are several periodontal procedures that can be done prior to the construction of the bridge. These procedures will build up the tissue to its former height. The more your mouth has changed from its normal state, the harder it is to make new teeth look and feel natural.

Implant Crowns

Implant crowns are used to replace single or multiple missing teeth. They are either cemented or screwed-retained onto an implant fixture. The crowns are made of porcelain or resin and metal. But they have some significant differences from the natural teeth they replace. Teeth are supported by a root or roots that are irregular in shape. Implants are round. The cross-sectional of the implant will never match that of the tooth it is replacing. A multirooted tooth may be replaced by a single implant, so the manner in which an implant crown comes out of the soft tissue ridge will appear different from a natural tooth. There will be more space between the implant root and the adjacent teeth. Implant crowns are often cemented with temporary cement. This allows the dentist to easily take off the crown and evaluate how the implant is doing. Crowns on teeth are usually cemented with a final cement. Implant-supported crowns are wonderful, but not the same as natural teeth with crowns. Be prepared for some differences. Expect more maintenance on your part and in the dental office with crowns, bridges, and implants.

Smokers take note: There is a heightened risk of dental implant failures among smokers—as much as 20% greater failure rate!

Crowns: An Overview

Why would I need a crown (cap)?
1. A tooth has been so badly damaged by decay or so heavily restored by fillings that it can only be saved with cast restoration
2. A tooth has been treated endodontically (root canal treatment). These teeth are almost always restored with a cast restoration because they have lost a great deal of tooth structure from fracture, decay, or the drilling process. These teeth are prone to fracture under normal and light chewing forces.
3. The tooth needs to be used as an abutment (anchor) for a bridge to replace missing teeth.
4. Grinding your teeth, an improper bite, age, fillings and tooth decay can all be contributing factors in the wearing down, cracking or breakage of your teeth. 

What are dental crowns?
Dental crowns cover the entire visible surface of your affected tooth and add strength, durability and tooth stability. Click here to learn about the difference between crowns, bridges, and implants.

What kinds of crowns are there?
Expect to pay more for porcelain crowns because they are usually more time-consuming than gold crowns. Porcelain, porcelain over metal and gold crowns average between $600 to $3100 each in total cost. The new reinforced resin or bonded all-porcelain type costs more than other types, require more skill from your dentist and the lab, and may exceed your insurance plan coverage for crowns.

• Resin and Porcelain Crowns

• The new reinforced resin or bonded all-porcelain type of crown as the nicest appearance. This crown can be made from pure ceramic or a new reinforced composite resin, and is almost indistinguishable from natural teeth. Thew new bonding technology involved provides an exceptional bond to your tooth. It is metal-free, and thus satisfies the needs of patients with metal sensitivities. When correcting your back teeth with bonding, the cosmetic dentist will perform a tooth colored onlay. This type of procedure is used to correct only those parts of the tooth that are in need. This is a metal-free procedure. 
• Advantage: Porcelain crowns or new reinforced resin are considered to be the most aesthetically pleasing, as it is so easily matched in color to the surrounding teeth
• Disadvantage: The thickness of the porcelain required for pleasing aesthetics also requires that more tooth structure needs to be removed. It is more difficult for your cosmetic dentist to get an ideal fit where your gum meets the crown. Gingival inflammation appears to be more common with porcelain crowns that gold crowns. All-porcelain crowns require a higher skill level from your dentist and lab.
• Crowns Made of Gold

• Gold crowns are appropriate when appearance is not a priority to you. The gold metal is extremely workable, making gold crowns a more precise fit than any other type. While there exists a slight possibility of chipping with porcelain crowns, gold crowns provide no such possibility.
• Advantage: The preparation of a tooth for a gold crown is the simplest and least complicated preparation as there is minimal tooth structure removal with as much as possible of the healthy tooth structure remaining untouched. While porcelain is hard by comparison, it may cause wear on opposing teeth over the years where goal is not as likely to do so. Gold is also easier to fit to the area where the tooth and crown meet for a better fit. Gold is also a healthier environment for the gum tissue.
• Disadvantage: The cosmetic aspect, unless it is being used in the back of your mouth
• Porcelain and Metal Crowns

• For a very natural appearance, porcelain fused to metal crowns are the answer. However, they have a metal substructure and require an opaque below the porcelain. This can make the translucency of natural teeth difficult to replicate. Occasionally, a darker line will be visible at the edge of the crown, near to your gum when it recedes with age. 
• Advantage: Porcelain fused-to-metal crowns have a very natural appearance
• Disadvantage: They have a metal substructure and require an opaque below the porcelain. This can make the translucency of natural teeth difficult to replicate. Occasionally a darker line will be visible at the edge of the crown, near to your gum when it recedes with age
• Types of Porcelain
• There are two types of porcelain - felspathic and pressed ceramic porcelains. The felspathic type is the original method that has been around for 20 years. Ceramist in a dental lab bakes porcelain onto tin foil and then heats it in an oven. The Ceramist is able to create tints and opaques inside the porcelain to give the natural look we seek.
• Pressed ceramic is created from a single ingot. The single ingot is milled in one piece to create the desired shape. The stains and opaques are applied only to the surface of the porcelain to give a natural look.

How do I choose a color for the dental crowns - how white should it be?
Whiten your natural teeth to either the level of whiteness you want or to the brightest they can be. Your cosmetic dentist will then have the crowns made to that color. Teeth are of course not monochromatic, so typically more than one color is used to used a very natural look. This color variation is critical in avoiding fake or artificial looking teeth. It is the internal contrast of colors that help create vitality. The internal play of light on the porcelain in the restoration helps to create this vitality. Surface texture is also very important, and helps to break up light reflections and make the crown look more natural.

There is no one standard system in the dental field to measure and determine tooth color. The most often heard about, however, is the Vita shade guide. This guide divides tooth color into four basic shade ranges:

A (reddish brown)
B (reddish yellow)
C (gray)
D (reddish gray)

In the A range, there are five level of darkness. Ranges B, C, and D, each have four levels.

Not all of your teeth are the same natural color. Usually your eye teeth tend to be darker than the others, your front teeth are typically the whitest, and molars tend to be a shade between the two. The goal for everyone is to achieve their individual optimum whiteness while still looking natural.

Most dentists will show you a shade chart for your to pick from. Keep in mind, with a good cosmetic dentist, this is merely a starting point. Other considerations when determining the color of crowns for each patient are your complexion, hair color, the color of your natural teeth and even your eye color.

What is the procedure?
- Preparing (drilling) the tooth in an appropriate fashion for the type of crown chosen
- Making impressions of the prepared tooth, opposing teeth, and the occlusal (bite) relationships
- Selecting a shade for tooth-colored crowns
- Fabricating a provisional restoration that will remain in place while the crown is being constructed
- Cementing or bonding the completed crown into position. If the work to be done is extensive, there may also be several appointments needed for preliminary seating (try-in) of the crowns or castings

What do I need to do BEFORE I get the crown?
It is important for the ultimate success of the crown(s) that you understand and can perform thorough plaque removal. You should immediately begin following the oral self-care instructions that you have been given. It will make the procedure more comfortable and efficient, and the resulting restorations will look better. Final impressions cannot be taken until the gum tissue is healthy. Crown lengthening is an oral surgery treatment that involves removing excess gum tissue around the upper teeth to make them look longer. Your cooperation is appreciated and necessary.

What do I need to do AFTER I get the crown?
As is true with your natural teeth and especially with teeth that have been restored with any dental material, you should avoid chewing on excessively hard or sticky foods after the crowns have been cemented. It is especially important not to bite down on hard foods with just one tooth. The porcelain material can fracture from the metal substructure under extreme forces. Anything you chew that could break a natural tooth could break a crown!

Be sure to brush and floss daily as instructed. We also advise using a fluoride mouthrinse as part of your daily routine. Please be sure to return for your regular examinations and prophylaxis (cleaning) appointments at the time intervals we suggest.

After observing these types of procedures for many years, we note that the gingiva (gums) can recede from the crown margins and the surrounding tooth structure may become visible. This recession usually takes place over a period of several years and may require restoration replacements or a periodontal plastic surgery procedure to correct it.

We expect that you will receive many years of service from the cast restoration.

If you have any questions about crowns and bridges, call our office and ask or set up an appointment. We have 3 convenient locations around Austin.

Implants: Procedural Overview

Compared to a routine dental filling or crown (cap), replacement of a missing tooth or teeth with implants is a more complicated and lengthy process. It will take several phases. A periodontist or an oral surgeon will place the implant surgically. Then we will place the tooth or visible portion.

Phase One
The specialist evaluates the position, suitability, and strength of the bone that will surround the implant. This information determines the length and width of the implants and how many implants will be necessary to replace the missing teeth. Impressions of all your teeth will be taken for study models in order to design the shape of the tooth or teeth to be implanted. A surgical guide will be made to indicate to the surgeon where the implants should be placed.  

Phase Two
Surgical procedure is done to place the implant in the bone. A local anesthetic is given, and the gum tissue is lifted to expose the implant site. The implant is placed into the bone and the gum is closed over it. You will not see the implant while integration with the bone takes place. The integration takes 4 to 6 months. After this time, the site is opened again and a healing collar will be threaded into the implant. This will guide the tissue into a shape that is needed for the future crown(s). The time that the healing collar needs to be in place will vary from person to person, but will be at least several weeks.

Phase Three
Once the tissue shape is sufficient, specific attachments and components will be fitted to the implant. The implant components are similar in function to the wall or plaster anchors used to hang pictures on drywall. The healing collar is removed. Implants transfer copings, analogs, and other items are used to take an impression of the site. The healing collar is then put back on. The impressions and implant components are sent to the laboratory for fabrication of implant posts and temporary acrylic crowns.

When the temporary crown or bridge is returned from the laboratory, the healing collar is removed and the implant attachments are fasted to the implant. The temporary crowns are then seated and adjusted. They will be held in place by temporary cement or with screws, depending on your certain situation. We will explain the advantages and disadvantages of each in your particular case at the time you decide to have the implant

Temporary crowns are placed because the bone that supports and surrounds the implant must be given the opportunity to be put into function gradually. Implant techniques dictate that the implants be slowly brought into biting function. This means you will be returning several times to have more acrylic added to the temporary crown. After the implant and temporary crown have been in biting function for a few months, the final crown(s) will be fabricated and cemented or screwed into place.

Maintaining All Your Teeth
To keep your implants and your natural teeth healthy and functional for the longest time possible, clean the implant and your other teeth daily, as instructed. You will also need to come in for dental hygiene recare appointments at a 3- to 4-month interval. You have invested time and money in these state-of-the-art tooth replacements. Maintaining them as instructed will give you the best chance of success.

We feel that the benefits of replacing teeth with implant-supported crowns and bridges far outweigh the inconvenience of the long start to finish time. This is especially true when the teeth on either side of the implant are sound, unfilled teeth that would not otherwise require dental treatment. Implants help you preserve your nature tooth structure.

If you have any questions about dental implants, please feel free to ask us.