Dental implants are artificial tooth roots that are surgically placed into the jawbone to support a replacement tooth or bridge. They are a popular and effective option for replacing missing or damaged teeth, providing a permanent solution that looks and functions like natural teeth. There are different types of dental implant available, each with its own advantages and disadvantages. In this article, we will discuss the most common types of dental implant and their characteristics to help you understand which option may be best for you.
The types of dental implants differ based on the type of classification. In general, when it comes to the types of dental implant, the most basic divisions are as follows:
Types of dental implant based on their location in jaw bone
- Endosteal or intraosseous: These type dental implants are considered to be the most reliable and frequently used type of implant. They are suitable for a wide range of individuals seeking tooth replacement. Typically, these implants are screw-shaped and are inserted into the jawbone using a dental drill. Over time, the bone gradually grows and fuses to the surface of the implant, leading to integration with the jawbone.
- Implant on bone or subperiosteal: A subperiosteal dental implant is a type of implant that rests on top of the jawbone, rather than being anchored within it. This implant consists of a metal framework that is placed beneath the gum tissue and contains one or more rods. Once the gum tissue has healed, the implant remains in place, with artificial teeth attached to protrusions that extend above the gumline. This type of implant is often recommended when the patient lacks sufficient jawbone density to support traditional implants or other tooth replacement options.
Subperiosteal implant is used only if the patient’s jaw bone is not suitable to hold a normal implant or the person does not want to perform dental bone grafting before the surgery to place the implant in the jaw.
Zygomatic implant: This type of implant is the least used and its operation is complicated. This type of implant is used only in cases where there is not enough jawbone for an intraosseous implant. Zygomatic implants are placed in the cheekbone, not the jawbone.
Types of intraosseous implants
- Screw-shaped implant (conventional dental implant): screw-shaped implant is the most popular and common type of dental implant all over the world. Since this implant acts like a tooth root and has a similar shape, it is also called a root implant. The screw-shaped implant itself is designed in different shapes.
Blade Implants: One of the first types of dental implant used in North America was the blade implant, which is now rarely used. Because the screw implant has more advantages, most of the implant manufacturing companies have switched to it and no longer offer bladed implants. In the blade implant, a channel was created in the bone and the implant blade was placed in it, and in the last step, the dental veneer was attached to it. The blade implant can be single or multiple.
Transosseous dental implant: Transosseous dental implant is a very stable implant that works like a standard four-screw implant. This type of dental implant is placed under the jaw and protrudes from the upper part of the jaw. A bar is attached to it so that the denture can be mounted on it. Few dentists perform this treatment because it is very difficult and requires a lot of skill and in most cases hospitalization. However, in situations where the mandible is very weakened and reduced or very thin, this method is a good alternative to the usual implant.
Types of dental implant in terms of length and diameter
Implants are also classified according to their size. Based on this, the types of dental implant are:
- Standard or normal implants: its diameter is between 3.5 and 4.2 mm. This implant is usually used for the front of the mouth.
- Wide implants: The diameter of these types of dental implant is between 4.5 and 6 mm and they are usually placed in the back of the mouth (instead of big molars).
- Mini implants: Its diameter is between 2 and 3.5 mm and it is mostly used in those who do not have enough space in the mouth to plant a normal implant. Mini-implants are also used in cases where the jaw bone density is not enough.
Types of dental implant in terms of body surface
Initially, dental implants were made with smooth titanium surfaces. However, implant designers have since developed various designs with the goal of maximizing the implant’s surface area for better bone adherence. Surface roughening, for instance, increases the contact area of the implant, thereby enhancing its stability. Additionally, some implants are coated with a layer of hydroxyapatite to improve the connection between the implant and the bone. This is because hydroxyapatite is the same material that comprises bone tissue. Overall, these design modifications have contributed to the success and longevity of dental implants.
While surface roughness can enhance implant stability, it may also increase the risk of contamination and infection. Consequently, dental implant manufacturers have developed alternative designs, such as implants with smooth surfaces or those with both smooth and rough areas. One company, for instance, has developed an implant with microscopic gouge-like areas on the surface, which significantly increases its surface area. This allows for the use of smaller implants with greater stability, particularly in patients with low bone volume. These innovative designs are helping to improve the safety and effectiveness of dental implants.
Types of implants in terms of abutment connection
The head of the dental implant is the place that must be connected to an intermediary piece called the abutment, and the dental veneer is also installed on the abutment. The abutment acts like a prepared tooth that is ready to be covered and holds the crown.
The implant head is divided into three categories in terms of connection to the abutment:
- Internal hexagonal connection: The hexagonal shape of the implant head is a hole into which the abutment is inserted and screwed (female connection).
- External hexagonal connection: The hexagonal shape of the implant head is a projection where the abutment is screwed (male connection).
- Internal octagonal connection: The hole of the implant head has an octagonal shape into which the abutment is inserted and screwed (female connection).
Types of dental implant in terms of body shape
- Conical screw
- Smooth screw shape
Types of implants in terms of connecting the crown to the abutment
- Cemented: In this method, the crown is attached to the abutment with dental cements. Exactly as it is done when veneering a natural tooth.
- Screw retained: In this method, the veneer is attached to the abutment with a screw. Then, the place of the screw on the tooth is filled and smoothed with a tooth filler such as dental composite.
Types of implant-based prostheses
- Single implant: It is the same as normal implants, where a tooth crown is installed on each implant base.
Dentures based on mini-implant: It is one of the implant prostheses that is used in those who have lost most of their teeth or all of them. This method is cheaper than placing single implants and requires less surgery and incisions. Also, due to the use of mini-implants instead of implants, the surgery is easier and the recovery period is shorter. However, you should be aware that due to the thinner mini-implant, its resistance to pressure is also lower.
All on Four: In this method, a complete set of upper or lower dentures is fixed on four implants. The advantage of this method is that there is no need for bone grafting and multiple surgeries for many implants, and the cost is much lower. But the problem is that while you are waiting for the bone to fuse, you have to be careful about what you eat so as not to put pressure on the implants. After six months, when the implant has hardened, the main denture is prepared and mounted on the implant, and the eating restriction is over.
Implant-based bridge: Prosthesis is similar to a normal bridge, but instead of using natural teeth for the support of the bridge, implant teeth are used.
Types of dental implant in terms of treatment stages
- Immediate implant: In the immediate implant method, in the same session as the damaged tooth is extracted, the implant is placed in the bone and then the cover is attached to it. Of course, this cover is temporary and you are not supposed to chew food with it because no pressure should be applied to the implant. After a few months, the main crown is attached to the tooth.
One-stage implant: In this method, after the implant placement surgery, the implant is closed with a healing screw, but the gum is not stretched over it, but the gum around the implant is sutured. This is done so that a few months later, when it’s time to attach crown, there is no need for another surgery to open the implant. In a one-stage implant, the tooth space remains empty for several months until the bone fuses to the implant.
Two-stage implant: In this method, two surgeries are needed. One time to place the implant and the second time to open the gum on the implant and connect the abutment and healing cover. However, the second surgery is very simple and has a short recovery period. Its advantage is that the implant is better protected under the gum and the risk of contamination or pressure is less.
Different types of dental implant are available, each with unique characteristics that can suit a wide range of patient needs. Endosteel or intraosseous implants are the most commonly used and reliable type, while subperiosteal implants offer an alternative for patients with insufficient jawbone. The surface of implants has been optimized over time to increase contact with the bone, but careful consideration must also be given to reduce the risk of infection. Lastly, the design of implant heads and connections has evolved to improve their functionality and flexibility. With these advancements, dental implants continue to provide patients with a comfortable and functional solution for tooth loss