Mobile dental NOG-types used in working dental models
A working dental model is a model made from the mold taken from an intervention in the mouth (in the fixed prostheticsthat is preparation of the teeth) and on which it is directly modeled and a fixed prosthetic construction is made. We pour a hard or super hard plaster. The mold is made first by mixing the super hard plaster, a small quantity is poured on the protruding part of the mold (distal part of the palate) by tapping in slowly it slides in the lumen of all the molded teeth. In this way the water and air are squeezed outso there aren’t any defects or porosity on the molded movable dental nog.
Today the dental model making is imperative, and the whole laboratory making of the artificial dental crowns taken from the working models (knows as “master” models) are mobile nogs that can be taken out of the rest of the mold mutable times and again put back in the completely same position. The reason is that, the removed nogs very easy to approach, model and control the precision of the gingival edge of the artificial crown, especially from the mesial and distal side where there is a chance of a small gap. The second reason is that some particular widely accepted models for making an envelope as the first phase of the modeling of the crown (for example: making an envelope by wrapping it in plastic foil also known as the Adapta-system or a model made by dipping in molted wax) they can be made only if the working nog is not mobile. In a working dental model is made with a mobile nog, there are a number of ways of making that: with Ney metal stakes, Trey- model- system with tray leading grooves and with separation, with root continuance from plaster or peg, with galvanization, with a mobile periodontium (his regards the surrounding gingival, and not directly on the movable working log.)
The goal of the study is to explore methods and apparatus for making models with movable dental nogs and their use in today’s modern practice.
For realization of the set goal a research was made and information was gathered from different manufacturers of apparatus and methods for making models with movable dental nogs. By using the Pindex apparatus we can drill channels in the plaster for placing double (Duplex) stakes, by using the Top Spin (automatic laser drill) a laser drill is make and placement of the stakes for making movable dental nogs in the dental practice. By using different methods and apparatus in the dental practice we get working models with movable dental nogs which secure better retention, stabilization and orientation for rightful acting.
Key Words: Apparatus, dental nog, dental prosthetics, models, modern methods.