Dental Implant Prostheses: What Is The Best Choice?

Implant dentistry is a rapidly growing industry both in popularity and demand. It was Initially introduced a while ago by Swedish orthopedic surgeon Per-Ingvar Branemark as a treatment for his completely edentulous patients. After its introduction, the technique quickly grew and gained recognition as a good approach for other dental treatments too since it offers plenty of benefits when compared with the traditional approaches such as fixed bridges or Removable dental prostheses. Most importantly, the use of these implants eliminates the involvement of the adjacent teeth and also helps to maintain the health and structure of underlying bone.

If you are thinking about getting a dental prostheses, you may be wondering what one to get. When it comes to dental prostheses, patients are often provided with two choices — cemented crowns or screw retained crowns. The last option is more expensive though there aren't actually that many signs that they offer any significant long-term benefits for patients.

We are hear to tell you exactly what you need to know about your options for dental poshtheses. Let's take a look at the options together.

General features of dental implants

So-called root form implants are by far the most commonly used type of dental implants. They are designed to mimic the shape of natural teeth. Dental implant is based on the fixture which is a screw-like component surgically inserted into the bone. The fixture is usually made of pure titanium or titanium alloys. Titanium can become osseointegrated, i.e. it forms a direct structural and functional connection with the surrounding bone tissues. 

The process of osseointegration takes several months. Upon completion of this healing period, a crown is fabricated and attached to the implant. Crown can be either screw retained or cemented to the implant. While cemented crowns are permanently attached to the implant, screw retained crowns can be removed, if necessary. This was traditionally considered as an advantage since the removal of the crown might be needed to address problems with implant or surrounding tissues.

Cost versus quality: real value for money?

Because of more complex lab procedures involved, the screw retained crowns tend to be more expensive (by a factor of 1.5 to 2) than cemented ones. The conventional laboratory facilities are sufficient for fabrication of cement retained restorations, while screw retained restorations require additional components. Higher cost also means that patients have higher expectations in regards to the quality of crowns, their longevity and ease of maintenance. But does the more expensive technology really deliver the value for money?

Advantages and disadvantages of different types of dental crowns

Which type of crowns – cemented or screw-retained – is better is a hotly debated topic among both researchers and dental practitioners. There are numerous articles analyzing the advantages and disadvantages of both techniques. They scrutinize various particular aspects of both restorations, problems and complications usually encountered and applicability of both methods to a variety of practical situations. But even the most recent reviews of the problem don’t provide a definitive answer to the question which technique is better. There are several aspects that have to be taken into consideration when deciding which type of implant supported crown has to be used in each particular case.

Read More: Dental Implants as a Solution to Missing Teeth

The value of retrievability of screw-retained crowns is questioned by many now, since the rate of complications with modern implants seems to be no higher that with natural teeth. Since it is considered perfectly acceptable to cement the restoration on the natural teeth, it is reasonable to ask why implants have to be treated differently.

Complication Rates Differ For Two Types Of Crowns

Porcelain fracture is a frequently observed complication with all dental crowns. Significantly higher rate of ceramic fractures was reported in a number of long-term studies. In one recent report, the rate of fracturing was 38% for screw retained crowns compared to only 4% for cemented crowns.

The problem of gum inflammation and other peri-implant health issues (bleeding, soreness etc.) can be of significant concern with the use of cement retained dental crowns. Many dentists believe that these problems can be reduced with the use of screw retained crowns.

This opinion, however, contradicts to the recent findings published by a group of dentists from Israel. They performed the so-called “split mouth” long-term evaluation of gingival health in patients who has both cemented and screw-retained crowns in the same positions on two different sides of the mouth. 

Gradual loss of the jaw bone surrounding the implant is another potential problem that can eventually lead to the loss of implant. For this reason the measurement of bone loss is widely considered as an indication of the implant’s clinical performance. Again, the opinion of researchers seems to be divided here.

Many authors don’t find any differences in the clinical behavior of peri-implant bone between the two types of implant-supported crowns, while others report a smaller bone loss with cemented crowns. In the long term, the bone loss seems to be small for both types of crowns, though. Many researchers believe that this factor should not be decisive in the selection of prosthesis type.

Special situations

Some specific situations can indicate the use of either screw retained or cemented crowns. Screw retained restorations are preferred when technical or biological complications in the future are anticipated. This is the case, for example, with the large, full-arch reconstructions. These reconstructions require maintenance and repair more often, and are more prone to complications. The possibility to easily remove and adjust them does, therefore, provide a clear advantage.

The same applies to the patients who are expected to lose more teeth in the future. The possible need to modify the framework of prostheses in the future should be catered for from the beginning of treatment.

In those cases when patients are prone to gingival problems such as inflammations and gum recession the screw retained crowns are also advantageous. They can be easily removed to address the underlying problem of soft tissues and modified to adapt for a new situation, when necessary.

Read More: Impact Of Poor Dental Health

Conclusion

When it comes to choosing between the screw retained and cemented crowns, two major questions should be answered:

1. Is the probability of future complications low enough to go ahead with permanently cementing a given prosthesis?

2. Does the retrievability of more expensive screw retained prosthesis represent the value for money in a given case?

Eventually, the choice of a particular type of restoration lies in the hands of practitioner and is dictated by many factors. Depending on the particular features of each individual case, both types of restoration have to be considered. 

A number of special situations, however, favor the use of one of the systems.