Position of crown margin in relation to the tooth preparation line.

Background: It is of paramount importance to have the crown margin precisely adjusted to the preparation lines of the teeth in order to reduce the bacterial plaque which is known to cause inflammations of the periodontal tissues.

Aim: The aim of the present study was to determine the position of the crown margin in relation to the preparation line in axial and transversal directions for various types of crowns.

Material And Methods: The study included 89 extracted teeth with the attached restorative construction (crown or crown bridge) divided into groups by types of tooth and construction.

The impression as a means for analysis of clinical mistakes in fixed prosthodontics.

Earlier and more recent clinical observations show that mistakes made in the early clinical stages of treatment have a negative effect on the time of effectiveness of the prosthetic treatment and its medicobiological value. Finding the most common mistakes and deviations from the clinical and laboratory protocol is of primary importance for creating a qualitative clinical technique and adequate training programs. On the other hand it is difficult for the practicing dentist to perform self-control in his everyday technique for preparation and taking impressions.

Correlation between overcontouring of fixed prosthetic constructions and accumulation of dental plaque.

Introduction: In prosthetic treatment with fixed prosthetic constructions the reproduction of the dimension and form of natural teeth crowns is important for the preservation of normal articulation-occlusal relationship as well as for periodontal health. THE AIM of the study was to evaluate to what degree there is an attempt to preserve and reproduce the natural dental contour in everyday dental practice and its impact on plaque accumulation.

Materials And Methods: The study was performed in patients with different types of fixed prosthetic constructions - metal, metal-ceramic and the combination of metal/plastic with intact symmetrical homonymous teeth.

Comparative evaluation of two commonly accepted tests for adjustment of fixed prosthetic constructions.

Regardless of the great advance in prosthetic dentistry related to the development of new more elaborate materials and methods, the dentist must often correct some defects of the newly fabricated prosthetic constructions. In dentistry practice worldwide two tests for adjustment of fixed prosthetic constructions are applied most often - the silicone test and the suspension of Fe2O3 (rouge) and chloroform. The capabilities of the suspension of chloroform and rouge to assess the preliminary contacts between the prosthetic construction and the dental tissues haven't been reviewed in the dentistry literature in Bulgaria.

[A device for thermo-compressive formation of plastic foil for stomatological purposes].

A device is proposed, by which bigger plastic details for stomatological purposes can be formed via high air pressure. For that purpose, a gas flow is led away to a special bell through an armoured rubber hose from the compressive installation of the somatological unit. The plastic foil is fixed by a clip-holder, adjusted also for work with basis-plaques.