METHOD OF CONTROL AND CORRECTION OF THE EDGE OF THE ARTIFICIAL CROWN TO THE GUM AGGER
In clinical practice, after prosthetic repair with non-removable dentures (crowns, caps), complications often occur in the form of chronic inflammatory processes of the underlying gingival tissue (gingivitis, localized periodontitis, etc.) due to the shortening or excessive lengthening of the edge of artificial crowns, which cannot be visually checked stage of prosthetics, both clinically and technologically. According to several authors, the shortening of the crowns in the cervical region is up to 28.9%, excessive elongation to 39.7%. In the literature there is no clear consensus on the prevention and elimination of such complications. There is also no generally accepted method and tactics of fitting the edge of the artificial crown to the gum agger, which does not allow visual control and correction. Study purpose. Development of methods for fitting crowns and preventing inflammation of the gingival margin after prosthetics with non-removable dentures Material and methods. 54 patients with various defects of hard tissues of teeth and dental rows were made with 957 artificial crowns: 267 stamped, 214 solid, 68 plastic, 39 ceramic and 369 metal-ceramic artificial crowns. To assess the quality of fit and correction of the edge of the artificial crowns to the gum, the method of applying the full or partial anatomical impression proposed by us was used. The essence of the proposed technique is that after the clinical fit of artificial crowns on the prepared teeth, a complete or partial anatomical impression is removed from the tooth row, for example, with alginate masses. In this case, the shape of the impression depends on the number of fitted artificial crowns. The next point is to remove the artificial crowns from the prepared teeth and install them in the corresponding cell in the anatomical cast. An important step is the visual assessment of an anatomical cast with crowns or caps, where the picture of the ratio of their margin to the gum agger is reliably visually reconstructed. Moreover, the excessively elongated edges of the crowns protrude above the surface of the impression, which are shortened to the desired value (0.5-1 mm) by means of cutting tools. Inconsistently covering the neck of the teeth and with shortened edges, artificial crowns are sent for alteration. Study results. During the implementation of the research task, a method was developed to control and correct the edge of artificial crowns, caps to the gum with the help of removing a partial or complete anatomical cast of dentition with fixed fixed prostheses. When using this method of control, it was found out that 957 artificial crowns and caps 380 (39.7%) did not meet the clinical requirements: excessively elongated margins in 178 (46.8%) cases, shortened cervical areas 92 (24.2%) and loosely covered the neck of the teeth 110 (28.9%). The excessively elongated edges of the crowns were adjusted to the required value, i.e. protruded above the surface of the anatomical impression by 0.5-1 mm. Poorly made crowns and caps after the rework were reattached and fixed on the dentition. Remote control examinations conducted over three years revealed chronic inflammatory processes of the form of gingivitis in only 6 (11.1%) patients. Conclusion. The use of the proposed method of correction of the edge of non-removable prosthesis with the help of a partial or complete anatomical impression can be an effective technique for fitting artificial crowns (caps) to the gingival margin and contributing to the reliable elimination of chronic complications.