A dental implant (also known as an end osseous implant or fixture) is a surgical component that interfaces with the bone of the jaw or skull to support a dental prosthesis such as a crown, bridge, denture, facial prosthesis. The basis for modern dental implants is a biologic process called osseous integration where materials, such as titanium, form an intimate bond to bone. The implant fixture is first placed, so that it is likely to osseointegrate, then a dental prosthetic is added. A variable amount of healing time is required for osseointegration before either the dental prosthetic (a tooth, bridge or denture) is attached to the implant or an abutment is placed which will hold a dental prosthetic.
Success or failure of implants depends on the health of the person receiving it, drugs which impact the chances of osseointegration and the health of the tissues in the mouth. The amount of stress that will be put on the implant and fixture during normal function is also evaluated. Planning the position and number of implants is a key to the long-term health of the prosthetic since biomechanical forces created during chewing can be significant. The position of implants is determined by the position and angle of adjacent teeth, lab simulations or by using computed tomography with CAD/CAM simulations and surgical guides called stents. The prerequisites to long-term success of osseointegrated dental implants are healthy bone and gingiva. Since both can atrophy after tooth extraction pre-prosthetic procedures, such as sinus lifts or gingival grafts, are sometimes required to recreate ideal bone and gingiva.
The final prosthetic can be either fixed, where a person cannot remove the denture or teeth from their mouth or removable, where they can remove the prosthetic. In each case an abutment is attached to the implant fixture. Where the prosthetic is fixed, the crown, bridge or denture is fixed to the abutment with either lag-screws or cement. Where the prosthetic is removable, a corresponding adapter is placed in the prosthetic so that the two pieces can be secured together.
The risks and complications related to implant therapy are divided into those that occur during surgery (such as excessive bleeding or nerve injury), those that occur in the first six months (such as infection and failure to osseointegrate) and those that occur long-term (such as peri-implantitis and mechanical failures). In the presence of healthy tissues, a well integrated implant with appropriate biomechanical loads can have long term success rates of 93 to 98 percent for the fixture and 10 to 15 year life spans for the prosthetic teeth.
The implants are manufactured from biologically neutral pure Titanium.
Titanium is proven to be acceptable by the human body and it will not cause material-related rejection.
The categories of dental implants will be selected by the doctor depending on your specific needs and general dental condition. You would require an x-ray and/or CT scan to evaluate the amount of bone remaining, models of your mouth to determine space available and a thorough examination to decide which type of implant can help you the most.
Immediate Loaded Implants: whereby the temporary or permanent fixed prosthetics is loaded onto the implant posts immediately or shortly after placement of implant post.
Conventional Implants: done in two phases – first phase, surgical placement of the implant posts is done. The implant post is left to heal for at least 6 months before second phase whereby the fixed prosthetics on implant is done.
Benefits of Dental Implants
- Regain your confidence and increased quality of life
- Reduce size and construct a more natural functional bridge or denture
- No need to trim the adjacent teeth to form the conventional bridge
- The solid anchorage of the dental implant will allow you to increase your chewing pressure, so eat anything you want
- Improves speech as compared to having dentures
- Prevent further loss of teeth and bone support
- Young, natural appearance
- Expected lifelong replacement for lost tooth
- No slipping, sliding clicking dentures or worrying about your dentures popping out in embarrassing situations.
Dental Implant Restoration Types
Single Tooth Implant
Single tooth implant restoration consists of three separate parts. Namely, the implant’s figure which replaces the tooth root, the abutment which will support the crown and the prosthetic crown. The crown can be cemented onto the post (abutment) or held in place with a screw.
Implant Supported Dentures
Implants allow you to wear full dentures and partial dentures without worrying that they will slip or fall out. Having implants to support these dentures also means that the base of the denture can be made much smaller and more comfortable. The dentures may be fixed, using bridges, or removable, using over dentures or partial removable dentures.
For over dentures, implants with screws placed in the jaw will serve as attachments for a metal bar, which will help support a removable denture. Use of 2 to 6 implants may be used for stability, as necessary. The new denture snaps over the bar and is stable and very retentive. The completed fixed-detachable denture sits on top of the implants above the gum tissue.
Multiple Tooth Implants
Implants are stronger than the natural tooth roots, therefore several missing teeth can sometimes be replaced with fewer implants. For example three missing teeth can be supported by two implants or four missing teeth can be supported by three implants and have the bridge restored over those implants.
An Implant Bridge is very much like a conventional Full Coverage Bridge except the support is actually over implants rather than natural teeth. The implants themselves act as man-made roots. A great advantage is that this is self-supporting – unlike a tooth-supported bridge that puts a heavier load on the remaining teeth. Implants are a terrific choice for missing teeth.
Bone grafting procedures are usually necessary if there is not enough bone available to place dental implants or if any vital anatomy is in the way.
Today, Bone Grafting procedures have become almost an integral part of Implant Reconstruction. In many instances, a potential implant site in the upper or lower jaw does not offer enough bone volume or quantity to accommodate a Root form Implant of proper size or in the proper place. This is usually a result of bone restoration that has taken place since one or more teeth (if not all) were lost. Bone Grafting procedures usually try to re-establish bone dimension.
Many years ago the lack of bone posed a considerable problem and sometimes implant placement was impossible because of that. Today, however, we have the ability to grow bone where needed. This not only gives us the opportunity to place implants of proper length and width (and for Root form Implants we always try to go for as long and wide as possible), it also gives us a chance to restore the esthetic appearance and functionality better.
Maxillary sinus floor augmentation (also termed sinus lift, sinus graft, sinus augmentation or sinus procedure) is a surgical procedure which aims to increase the amount of bone in the posterior maxilla (upper jaw bone), in the area of premolar and molar teeth by sacrificing some of the volume of the maxillary sinus.
When a natural tooth is lost, whether through dental decay, periodontal or dental trauma, the alveolar process begins to remodel. The edentulous (toothless) area is termed a ridge, which over time usually loses both height and width. Furthermore, the level of the floor of the maxillary sinus gradually becomes lower. Overall, this leads to a loss of volume of bone which is available for implantation of dental implants, which rely on osseointegration. The goal of the sinus lift is to graft extra bone into the maxillary sinus, so more bone is available to support a dental implant.
It takes about three to six months for the sinus augmentation bone to become part of the patient’s natural sinus floor bone. Up to six months of healing is sometimes left before implants are attempted. However, some surgeons perform both the augmentation and dental implant simultaneously, to avoid the necessity of two surgeries.