Several options are available when it’s necessary to replace a missing tooth. Using a dental implant covered by a dental crown is the preferred solution since it behaves more like a normal tooth. I prefer to use the one-stage dental implant. Dental bridges may be a good alternative under certain situations.
Dental Bridge
A dental bridge requires two crowns adjacent to the bridge to hold it in place. So if there are already two crowns adjacent to the tooth in question, a bridge can be used.
A dental bridge might be the best solution if there is a defect in the gums that would prevent safe insertion of an implant.
A bridge might also fill the space more completely which might be important depending on the position of the tooth that needs to be replaced.
A dental bridge could be a good solution if replacing an existing bridge.
Dental bridges will sometimes be less expensive than implants depending on the situation.
To make a bridge you have to take all the enamel off on the teeth on either side of where the hole is. If those adjacent teeth already have crowns on them, then it is less disruptive to the adjacent teeth. You take off the old crowns and then create a 3-crown solution where the bridge crown is mounted on the two bracing teeth and cemented.
One problem with bridges is that since those teeth are connected together, you have to thread floss underneath them so it’s harder to keep them clean and the gums healthy around the teeth.
Even when bridges are less expensive they have inherent problems while implants solve many of those problems. In general, we choose implants over bridges.
Dental Implants
A dental implant is where we take a threaded titanium post, make a pilot opening into the gum and into the bone and screw the titanium post into the bone. The gums then must heal for a certain period of time. We can put a dental crown on top of that titanium post.
The crown then stands by itself, you can floss it like a regular tooth, and you don’t have to worry about doing anything to the teeth on either side as you would if using a bridge.
Dental implants have been done for 40 years. These original dental implants are a two-stage implant that many dentists still prefer. This type of dental implant is composed of two threaded posts, a threaded post that goes into a threaded post that serves as a sleeve. The first post is threaded into the bone and is covered with gum tissue. In order to allow the post to be completely covered with gum tissue, it needs to heal for 3-4 months.
Once healed, another surgery is performed where the gum tissue is reopened and the above-surface post is threaded into the below-surface sleeve. A few weeks of healing is usually allowed at this time. Then the crown can be mounted to the post.
This two-stage process is very expensive because of the multiple surgeries. Before screwing the implant into the bone, it also may be necessary to graft in artificial bone to make the bone large enough to hold the post.
The sizes of these two-stage dental implants are 3.5 millimeters (3.5mm), 4mm, 5mm and 6mm.
In the last ten years some research has indicated that in many cases it is unnecessary to cover up the implant. A one-stage implant reduces the cost because you reduce the surgeries and the components by half. I only do the one-stage method.
The two-stage is still necessary in the upper molar area because the bone density in the upper jaw is half that of the lower. Also, in the upper molars you have the sinuses so the bone density is low. Those upper molar teeth will always require the two-stage implant.
For the lower front teeth, the two-stage dental implant seems to have little advantage over the one-stage. The 1.8mm mini dental implants are used for those lower front teeth. The two-stage implant would be difficult to use for those teeth because there isn’t enough bone to hold the size of the smallest diameter two-stage implant.
Which dental implants to use depends on the strength of the bone. I use a wood analogy that I use to describe the 4 different types of bone strength in the jaw.
- The chin is like oak,
- Lower back jaw is like maple,
- The upper front jaw is like pine,
- Upper back bone where the sinuses are is like balsa wood.
With the lower front teeth, I could put a mini dental implant in and put a crown on that mini dental implant the same day since that bone is so strong.
The one-stage mini dental implant and hybrid mini dental implants are relatively new (10 years), I have been doing them for 5 years. The two sizes of one-stage implants I use are the mini dental implant (1.8mm) and the hybrid mini dental implant (2.9mm) which is nearly the size of the smallest two-stage implant (3.5mm).
I use the one-stage implant on any spot on the lower and anywhere on the upper except for the sinuses. The 2.9mm is small enough that I typically don’t have to graft bone or gum tissue.
With dental implants, an upper implant must heal for 6 months. A lower implant must heal at least a few weeks to see how the position of the gums change. A temporary denture is sometimes used to fit over the implant while it is healing.
When the implant is healed, I cement a crown over the post. The crown can be of the porcelain material covered over a metal that allows it to look like a real tooth.
When the two-stage dental implant is necessary, in the upper areas near the sinuses, I refer to specialists.
Although the one-stage implant is relatively new, there has been much research done on them. Gordon Christensen is a Prosthodontist (specialist in crown and bridge work) who founded a research facility called Clinical Research Associates in Provo Utah. He and his staff of dentists have been testing the smaller, one-stage implants for years in his research facility using these mini dental implants and hybrid mini dental implants.