The advantages of an immediate implant are
- fewer visits to the dentist for the patient and
- less stress due to fewer surgical procedures on the jaw.
An immediate implant only makes sense if the conditions are ideal. Otherwise, the immediate implant will not grow in correctly. Further, sometimes complex procedures may then be necessary. For example, it may be necessary to insert a normal implant with bone augmentation.
In the case of tooth loss or severe damage due to an accident, the jawbone is usually still intact. An intact jaw with sufficient solid bone substance is the prerequisite for an immediate implant.
If caries is responsible for the removal of a tooth, there must be no inflammation.
These conditions should be fulfilled for an immediate implant:
- There must be no acute inflammation, for example in the area of the root of the removed tooth.
- The gums must be firmly attached to the bone. Sometimes the gums become detached when the tooth is extracted. To prevent this, experts use special instruments (periotomes). These are very thin and sharp and thus protect the surrounding tissue. It is also possible to remove and insert additional connective tissue, for example from the palate.
- Sufficient stable jawbone must be available.
The condition of the jawbone is a key factor when deciding on an immediate implant. An X-ray is only of limited help in assessing the bone structure. Whether an immediate implant is possible can only be definitively assessed after the tooth has been extracted.
The jawbone must be able to hold the post of the immediate implant. Whether the bone density is sufficient for this only becomes apparent when the post is screwed in.
To do this, the doctor uses a device that works on the same principle as a torque wrench: when turning, the device measures the required force in Newton centimetres (Ncm). For an immediate implant, at least 30 Ncm must be displayed. The higher the value, the better for the immediate implant.
If 30 Ncm is not achieved, the doctor decides whether he or she needs to reschedule. For example, bone augmentation may be necessary first.
Structure of immediate implants
The basic structure of immediate implants is the same as that of a normal implant: the immediate implant is connected to the jawbone via a post. This is also called the implant body. It is used to anchor the dental prosthesis in the jaw.
In most cases, it is made of pure titanium or a titanium alloy. This material is generally established in denture technology due to its stability. Patients generally tolerate it very well.
Alternatives are immediate implants made of zirconium oxide ceramic. This material is increasingly being used and is also considered to be unproblematic. However, long-term results on the durability of these immediate implants are not yet available.
A crown is placed on the post. The crown is the actual visible prosthesis, i.e. the "new tooth".
Structure of a dental implant: the post serves as the root and the crown imitates the natural tooth and its function © ONYXprj | AdobeStock
Insertion of the implant
The size of the hole in the jaw is decisive for the implantation of the post. The space left by the extracted root does not correspond exactly to the shape of the post.
If the hole needs to be enlarged, a compactor is used, not a drill. This device pushes the bone material to the side as it rotates so that it is not lost. The material is still available for a good hold of the immediate implant.
Simultaneous augmentation, i.e. filling the hole, is also possible. The doctor uses a so-called bone replacement material for immediate implants. This slowly recedes over time. In this way, it ensures that the immediate implant grows in well.
Two different post shapes
Two different post shapes can be used for an immediate implant. The apical post is rather narrow, but has a deep thread. It therefore cuts into the bone like a screw when the immediate implant is placed. The deep thread provides additional support.
The alternative for an immediate implant is a coronal implant body. It is wider overall and has a shallower thread that becomes progressively narrower. With an immediate implant, it is narrowest where the post is widest. When the immediate implant is screwed in, it therefore ensures a slight compression of the bone.
The forces exerted during chewing are absorbed by this compacted area. This means that the immediate implant does not overload the bone.
With an immediate implant, soft tissue may also have to be transplanted. This creates a seamless seal.
The material of the permanent crown
The crown should resemble the natural tooth as closely as possible. To do this, the doctor takes a plaster cast of the teeth before removing them. This ensures that the artificial tooth fits perfectly into the gap. Only then can the immediate implant fully fulfill its chewing function.
Full cast crowns made of gold are no longer common, although they are well tolerated and long-lasting. Gold crowns stand out too much in the dentition.
Ceramic crowns
Nowadays, ceramic is the most popular material for crowns. Ceramic has a very pleasant behavior, among other things, plaque does not settle on it so easily. Ceramic reflects light in a similar way to a real tooth. As a result, the prosthesis is practically undetectable from the outside.
Doctors therefore usually recommend an all-ceramic crown for immediate implants. This crown does not contain any allergy-relevant components. It is therefore particularly suitable for people who are prone to allergies.
Immediate implants with all-ceramic crowns are generally the most expensive option. However, prices vary greatly. It can therefore be worthwhile for those affected to obtain quotes from various dentists.
Statutory health insurance companies only pay a fixed subsidy for dentures. It depends, among other things, on the type of tooth to be replaced, i.e.
- molar,
- incisor or
- canine tooth.
This also applies to an immediate implant. The patient must pay the difference themselves or cover it with supplementary dental insurance.
Alternatives to ceramic crowns
In recent years, a special ceramic called zirconium oxide has become increasingly popular for immediate implants. It is considered to be particularly durable, but reacts differently to light than normal ceramics. In order for the immediate implant to look like a natural tooth, it must therefore also be veneered.
A ceramic veneering crown can be a good alternative for the immediate implant. A less expensive metal framework is used for this. A complex procedure is used to fire layer after layer of a plastic material onto the framework.
This gives the immediate implant a ceramic effect that imitates natural teeth. However, this crown is cheaper than an all-ceramic crown.
However, it has the disadvantage that a fine metal edge may become visible when the gums recede. This can be prevented using special procedures. For example, a so-called ceramic shoulder can cover precisely this area.
The most favorable option for an immediate implant is a plastic-veneered crown. As with ceramic veneers, a metal cap forms the basis for the immediate implant. It is covered with a well-tolerated plastic.
Matching the color of the crown to the natural teeth
The dental prosthesis is made in the dental laboratory. The crown should meet aesthetic requirements. For this reason, it is matched to the natural teeth as closely as possible in terms of color and shape.
Nowadays, dental technicians apply color in several layers, for example. This imitates a natural tooth even better.
The shape and color of the finished crown can be touched up later. Of course, this is not possible with gold crowns. They definitely stand out and the color cannot be changed.
For the color of the dental prosthesis, the doctor compares various available colors with the natural shade of the tooth © Aleksandr Rybalko | AdobeStock
With an immediate implant, the supporting post is implanted directly after the tooth has been removed. However, the final crown may not be screwed on immediately afterwards. The treating dentist decides whether the immediate implant can be loaded directly.
There are basically two types of crowns: Immediate restoration and immediate loading.
Immediate restoration: Use of a temporary restoration
With immediate restoration, a temporary crown is placed on the immediate implant. It closes the gap in the same way as the final prosthesis, but is slightly flatter. This means that the temporary crown has no contact with the opposite tooth. The teeth therefore do not bite against each other.
This protects the inserted post and ensures good healing. The patient should do their part and try not to put any strain on this side of the jaw.
After a period of around eight weeks, the doctor replaces the temporary with the permanent crown. Now the immediate implant takes over the full function of the removed tooth.
Immediate loading: insertion of the permanent crown
With immediate loading, the doctor places the permanent crown directly. In this case, the chewing force of the jaw acts directly on the new post.
This immediate implant method was viewed skeptically for a long time. It was feared that it would not guarantee secure healing. The result would be a loss of the immediate implant.
However, this is countered by another phenomenon: the body uses its resources as efficiently as possible - if tissue or muscles are not needed, they regress. This also happens to the jawbone when a tooth is removed: It no longer needs to hold a root at this point and decreases over time.
Bone density and structure therefore deteriorate over time after tooth loss. Only a quick replacement can counteract this. Even with normal implants, patients should not wait too long. Otherwise there may be too little bone material left for a dental implant.
Stress is always a signal for the body to strengthen bones and muscles. Immediate loading with immediate implants makes use of these positive effects.
Various studies show that there are no significant differences between immediate loading and immediate restoration in terms of the immediate implant's chances of success. However, this only applies if all the prerequisites for a positive outcome are met.
Indicators that speak against immediate loading are not necessarily related to the condition of the jaw. Diabetes or heavy smoking can also worsen the prognosis for immediate implants.
Healing times and adhesive bridges
It is not always possible to place a (temporary) crown immediately after the post implantation. In some cases, the inserted post must first grow in. It must not be exposed to any stress.
This is similar to the normal implant procedure, where such a healing period is also provided for. Nevertheless, the patient does not have to leave the practice with a visible tooth gap.
One option here is an adhesive bridge (Maryland bridge). It is temporarily bonded to the neighboring teeth. The bridge ensures that the immediate implant is not loaded, but closes the gap visually.
This temporary bridge is fixed in place and is removed after around ten weeks. Only then does the doctor add the permanent crown to the immediate implant.
