Dental implants as bridges supports - a different concept

Indications for dental implants are widely known. One of them is the creation of missing supports for fixed prosthetics. Everyone knows, along with some positive qualities, what inconveniences removable dentures create. In contrast, dentures on implants create a feeling very close to that of natural teeth and therefore preserve the quality of life of the wearer.



Modern implants are of three types: enosal (screws, cylinders, plates), subperiosteal and transosal. Each of the types has a variety in design, but when an implantologist works with a given type, he cannot always master the even greater variety of clinical cases. Even more - it is impossible for one type of implant to be universal, ie using only it, to solve all clinical cases. Sometimes this is possible by using bone grafts in advance in the areas of the jawbones that are anatomically and physiologically unsuitable for the given type of implants. However, this prolongs and makes the overall treatment too expensive. Often patients refuse treatment because of the long duration and high cost. The clinician must make it possible to carry out the complete treatment with implants and fixed prostheses for optimal time and reasonable price. The concept I want to present to your attention comes to the rescue. Synthesized, it sounds like this: As much as where. In other words, to solve a case clinically, we place as many implants as we need and place them where we need them to prosthetic. In solving this case, we often take into account the presence and location of natural teeth, if any. In implant theory and practice there was such a principle that we should not combine implants with natural teeth when planning and making bridge prosthetic structures, but it did not stand the test of time and remained a purely theoretical statement.



When planning a classic orthopedic treatment, we generally use the well-known Kenedy classification for dentition defects, according to which they are four classes. When planning orthopedic treatment, where we will use either only implants or implants and natural teeth as bridge supports, we use the additional Kennedy classification (Fig. 1), containing six.
In fact, in our case we eliminate class V, because we have to replace a single missing tooth with an implant and a crown on it. Of course, in practice, we encounter a wide variety of defects in the dentition, but in the clinical interpretation, we will refer them to one of these six classes. Whichever of them, we can solve orthopedically with a removable prosthesis. However, if we want to prosthetic immobile, we will need implants as additional supports or as the only supports - VI class. Here we have to take into account the specific anatomical and physiological features of the upper jaw, where very often an obstacle for implantation is the maxillary sinus, and in the lower jaw - the mandibular canal. These two anatomical objects are very often located in such a way that they do not provide us with sufficient "bone height". In addition to it, however, in many clinical cases we need a corresponding "bone thickness", which too often for physiological reasons is not present. Finally yet importantly, in order to assess the type of implant, we need "bone quality" as a compact-spongiosa ratio and as a density of the spongiosa itself. The classification of Lekholm and Zarb (Fig. 2, 3) gives us a look in this regard as well.




Figure 2 shows, in addition to the atrophy at the height of the bone, its profile in section, as in the direction from A to E the possibilities for placement of intraosseous implants decrease - Fig.6.
Figure 3 shows well the ratio of compact-spongiosa as well as the quality of spongiosa. Cases 2 and 3 are most suitable for intraosseous implantation.
It is clear from the figures where what type of implants are most suitable, without the need for bone grafting.



Clinicians know that in practice, in the otherwise perfectly planned case of computed tomography, orthopantomography, the impression of the jaw, the type and thickness of the mucosa, as well as the ratio of movable and attached mucosa, as well as according to these classifications, etc., often occurs discrepancy between the treatment plan and the intraoperative finding. Then the implantologist must have a quick reaction and improvise.

Given the above, let us return to the concept of "As much as where." It is clear that we cannot always place as many implants as we need and where we need them, mastering one implantation method, having one implant system or several, but similar in type. There is a need to master several implantation methods and the availability of several types of implant systems in order to be able to implement the concept and improvise in case of accidents in practice, but ultimately to carry out the treatment of the patient.

I will offer you several orthopantomography illustrating clinical cases, planned and treated according to this concept, without the need for bone grafting.



Figure 8 shows a diagnostic orthopantomography of a 51-year-old patient in good general condition with a fully edentulousness Kenedy class VI upper jaw and a partially edentulous lower jaw, with all but 33 teeth available for extraction, and the implant has large bone resorption, in addition, it is clinically highly mobile, which makes it unusable. Thus, the lower jaw generally falls into Kenedy class VI. Orthopantomography and the study of the thickness and shape of the bone by the well-known method by multiple perforation of the mucosa and compiling the relief of the bone on a plaster model shows the type of implants that can be used and where what can be used. In principle, we need six supports on the upper jaw and five on the lower.

We satisfy the concept of "as much as where". We made metal-ceramic bridges. The case is 9 years old.

Diagnostic orthopantomography of a patient, a 54-year-old man in good general condition, does not want to wear a removable prosthesis. Up in the right edentulousness from 13 to 18 teeth, 21, 23 and 26 teeth strongly exposed from periodontitis with pathological mobility III degree, 24 - root. It's about I class according to Kenedy.

Fig. 11 shows the subperiosteal implant, the intraosseous implant in the tubercle area, as well as the intraosseous implants on the left. The case is under treatment. We performed a bone impression operation for a subperiosteal implant in the area of 27 teeth, after which we can make a metal-ceramic bridge.


The concept does not contradict the possibility, if necessary, to make bone grafts in certain areas of the jaws in order to place a certain type of implants, which in this case would be in the interest of the patient, as well as the possibility, in certain anatomical and physiological features be treated with the same type of implants.

Conclusion

In the last years of the last century, dental implants have established themselves as a routine method in dental practice around the world. Modern humanity, despite the progress of civilization in scientific and technical terms, is moving towards greater and earlier loss of its teeth. The cultural level of today's man sets ever-higher criteria for the restoration of his masticatory apparatus in case of partial and complete loss of teeth, both functionally and aesthetically. The solution is - fixed prostheses on implants. This requires appropriate theoretical and practical training of dentists in the field of modern implantology, ie. mastery of the methods for implantation of all known types of dental implants, a certain type of clinical thinking and on this basis the possibility of improvisation in their daily medical practic