Tooth gaps disrupt perfect closure and chewing harmony. Their effect on human organism are known. Tooth gaps can be eliminated by fix denture when adequate numbered and situated own teeth are present. In case of a low number or unsuitable teeth prosthetics are applied. Their disadvantages are known. In certain parts of such cases application of implants remains a possibility, that is a rather complicated intervention and raises several problems. Despite of successful construction, success is only partial, as with solving one problem, an other, hardly curable problem brings to surface, namely the patient's damaged psyche. Accomplishment of one or two end situations had been studied for a long time by professional researchers. The essence of ZX-27 Attractive Glass Abutment System is, that those who still have own teeth, but do not want prosthetics or implants can obtain fix dentures with this method.

Condition of introduction and application of a long last designed denture is that implantation should not be resulted in permanent and irreversible tissue damage. Secondary changes within the implant, that could cause alteration on the structure of the surface or modification of element composition due to solubility of the saliva, that is dissolution of substances from the glass should not occur.

Why the glass?

It was a long way to ZX-27 Attractive Glass Abutment System. As follows we can look into why the materials on trial did not work. Why the glass?

Fig.1. Heat modeling of general glass.

Following the trial of many experimental glaspolished while as a result of them it looses as much from accuracy that it did not live up to expectations, stub will not fit to the gum with whole surface. Things are the same with plastics,
similarly the processing causes trouble. Moreover
plastics are porous that causes food deposition
then inflammation. Furthermore most part of commercial plastics are not flexible enough and are not thermal resistant. In case of glass ceramics and ceramics, shrinkage after adaptation to the gum is problematic, furthermore
these are not really self cleaning because of porosity. General glasses also did not equal expectation, the causes will be mentioned later. After the trial of the mentioned materials, there was only one choice, namely the glass and a
special composition within In case of metals casted stub has to be processed, ses, ZX-27 glass served the listed view points.

Main characteristics of ZX-27 glass

General glasses did not equal expectation as dental glasses have to serve many view points at the same time, namely:
- meltablity
- workability
- rigidity
- chemical resistance

There is no such amongst general glasses, the main problem is meltablity and chemical resistance. General glasses can not
be heat-processed under dental technical circumstances. It can be fractured
during heating or invisible hair-crack may develop
that leads to fracture. Similar processes occur with cooling. Chemical resistance is the other problem. Saliva interacts the glass and evokes chemical reaction sooner or later. Meanwhile toxic substances, like plumb and barium get into the saliva from the glass. These substances are harmful to the human organism.
Conditions made on the utilizable glass:
- workability
- rigidity suitable to utilization
- chemical resistance and its effect on organism.

Good workability of ZX-27 glass under
laboratory circumstances is own to its high boron-trioxide content. That made the otherwise indispensable high alkaline content being reducible. Due to the low sodium content, corrosion does not cause local pH rise nearby the gum. The above assure dental utilization of structural elements made from ZX- 27 glass.

Contraidications of ZX-27

Contraindications of this way processed ZX-27 Attractive Glass Abutment System:
- Excessive deep biting
- Loose or shaky mouth works.

Indications of ZX-27

Indications and fields of utilization:
- unilateral status
- bilateral status
- in combination with implants
- supporting arching of large span bridges

Illustrations of indications were born from eleven
years' practical experience. Application of the abutment is safe with simultaneous employment of indications and acquired technology. The last ten years and large number of implantation irrespective of geographic situation have proved, that acceptance of the glass abutment - despite of previous reservation - was undiminished. This is
own to its greatness that lies in simplicity and to its increasedconvenience for the patients. Naturally several unanswered questions have escorted my work thereafter the start ten years ago. The first and most important is that general pathological thesis, whereas chronic irritation of on keratinized mucosa leads to development of keratinized mucosal epithelium, that is metaplasia, which in turn become dysplastic,
thus a precancerous condition develops.