January 19, 2022 Tri Le Dental implants are an incredible solution for missing teeth, but if you’re considering getting one (or more), you may be curious what a dental implant actually is. Although you can’t tell from the name, a dental implant system has three important parts that can’t all be placed in your mouth at the same time. They are, from bottom to top: the post, also known as the screw, body, or fixture the abutment; and the crown, also known as the prosthetic or the restoration. Together these components deliver a potentially permanent solution that looks and performs like natural teeth and resolves the bone loss and other issues associated with missing teeth. Let’s take a closer look at each… The Post: Anchoring the False Tooth What does the post do? The long-lasting effectiveness of a dental implant is due in large part to the stability provided by the post, or small metal screw. By surgically placing it in the jawbone (after the dentist drills a small hole, with computer guidance), the post is “rooted” in place. This hold becomes stronger with time, which is why the placement site for the post must be allowed to heal for about six months as the fixture fuses to the bone. What material is the post made from? This fusion can be made even stronger by using a post that’s coated with hydroxyapatite or roughed by grit-blasting or acid-etching to allow for more bone contact. The underlying material usually used for posts is titanium, although zirconia is quickly gaining popularity because it’s hypoallergenic (i.e. it won’t cause allergic reactions), heat- and corrosion-resistant, and also quite strong. Different post designs Implant fixtures are manufactured in a wide variety of sizes and even different designs, so that your dentist will have the perfect option available for your missing tooth, whether it’s a molar or an incisor. This includes “mini” implants that are long (up to 18 mm), skinny screws that can be fitted into tight gaps to anchor tooth implants. But conventional posts are fairly stubby and hollow so that the abutment can be attached on top. The Prosthetic: Fixing the Smile What does the prosthetic do? The prosthetic is sometimes called “the restoration” because it’s the part of the implant that restores your appearance by filling a missing tooth gap with what appears to be just another natural tooth. In almost every situation, it’s the only part of the implant that will be visible. It also functions like a tooth, meaning you’ll be able to eat whatever you like once everything heals (assuming the rest of your teeth are healthy). The 3 prosthetics used with implants Prosthetics for implants come in three types: crowns, bridges, and dentures. Multiple, consecutive tooth implants are usually achieved with a bridge, in which the pontic (the false teeth) is held in place by crowns cemented to the abutments capping the posts. A single missing tooth, however, is generally treated with a crown placed atop a single abutment and post, first with a temporary crown and later a final, porcelain one. Finally, an entire arch of missing teeth requires dentures. Unlike conventional dentures that are held in place via suction and/or glue, implant-supported dentures are an alternative solution that snap into place on multiple (four to six) abutments. These dentures may be made with either plastic or porcelain, with an acrylic base colored to mimic your gum line. The Abutment: Bringing It All Together What does the abutment do? Sandwiched in between the fixture and the restoration lies the abutment, sometimes called “the connector.” It functions like an adapter, with one side able to screw into the post and the other designed to adhere to the prosthetic. Different abutment designs The overall design of the abutment will depend on whether you’re having a crown, bridge, or dentures placed–an abutment for a crown is like a stumpy screw, whereas an abutment for dentures has attachments for snapping the dentures in place. Within these designs, the abutment may attach via an internal hex (hexagon) connector in the post head, an external hex connector so that the abutment sits on top of the post, or an internal octagon connector. Is the abutment placed at the same time as the post? Although the post, abutment, and a temporary restoration can all be placed at the same time, in some cases, the dentist waits to attach the abutment until the post has fused with the jawbone. This necessitates a second minor surgery to reopen the gum where it has grown over the implant post, so that the abutment can be screwed in. However, if the dentist uses a healing abutment–also called a healing cuff–this removes the need for a second surgery because this type of abutment extends beyond the gums, making plenty of room for the crown. Once the post has fused, the dentist then removes the healing cuff and places the final abutment and crown. Your gums may need minor reshaping to accommodate the size and shape of the crown, although a temporary crown can help contour the gums. What material is the abutment made from? As with implant posts, titanium and zirconia are the most common abutment materials. Some patients prefer zirconia’s tooth-colored quality when getting a crown or bridge as the abutment does protrude above the gum line. Dental Implant | Before and After Single- vs Two-Piece Dental Implants Although it’s now common for the post and abutment to be fused together as one piece during manufacturing, this method is actually pre-dated by a “two-piece” design. Here the post is placed and allowed to integrate into the bone for several months before the abutment is attached by cement or cold-welding. This procedure allows the dentist greater flexibility to utilize good available bone while still angling the implant appropriately, because the top of the post can be accessed and the abutment placed at the angle needed. With a one-piece implant, this is impossible. While a single-piece implant provides greater strength, is installed in a simpler and less expensive procedure, and can be placed in a narrow space, many dentists still opt for the two-piece design as the implant angle orientation is more forgiving. Each design has its place, however, and which is best for you depends on the unique circumstances of your mouth. Dental Implant FAQs How long do implants last? If you have good oral habits, implants can last a lifetime. Patients routinely get 25 or 30 years out of their implants, although the prosthesis sometimes requires replacement after 10-15 years due to wear and tear. How much do dental implants cost? With ancillary costs included, implants range from as little as $1,000 to as much as $4,800 per implant. The wide range is a function of a number of factors, including the complexity of tooth and root extraction, the number of X-rays needed, the selected restoration material, and more. That’s why we don’t give patients estimates until we’ve met with you–each patient’s situation is different (as is each dentist). What is the most expensive part of a dental implant? The post is typically the most expensive part, followed closely by the prosthesis. The abutment is by far the cheapest part of the three. Who is not a candidate for implants? Children and teens are not advised to get dental implants after losing a permanent tooth because the jawbone is still developing, and placing an implant in an underdeveloped jaw can create problems. Also, those who aren’t healthy enough to undergo surgery are not good candidates for implants. For patients unable to undergo surgery for implants, see your other options to replace missing teeth. Tri LeA practicing dentist since 1987, Dr. Le has been running successful dental practices in Texas with his wife Ann since 1990. A member of the ADA, AACD and AADSM, Dr. Le has also contributed to several leading dental journals.