Confection spoon
A ready-made spoon is an industrially manufactured, dental auxiliary instrument with which the impression of the upper or lower jaw is made.
variants
The auxiliary instrument, which is also called an impression spoon , is available
- in different sizes for different jaw sizes.
- differently designed for the upper and lower jaw
- designed differently for each
- fully dentate jaw
- partially edentulous jaw
- edentulous jaw
- with different retention elements.
Plastic impression material is poured into the impression tray and the denture or jaw impression is taken . The retention elements are intended to hold the impression material in the tray when the impression is removed. For this purpose, the impression tray can be provided with perforations through which the impression material passes during the plastic phase (impression tray according to Ash) or have a retentive rim that holds the material in the tray (rimlock tray).
Schreinemakers' impression trays are a special variant for taking impressions of the edentulous jaw. A range of plastic spoons was developed for the Schreinemakers impression method. There are 13 different sized plastic spoons for the lower jaw; 7 different sizes for the upper jaw. In order to determine the correct size of the impression tray for an alginate impression, the maximum width of the lower jaw between the trigona retromolaria is grasped paralingually with the caliper and a tray is selected that is more spacious by the thickness of the caliper.
In contrast to individual spoons, ready-made spoons are not precisely adapted to the patient's jaw. These are prefabricated stencils made of metal or plastic . They can be intended for single or multiple use.
application
Ready-made impression trays can only be used for difficult jaw conditions, i.e. those that deviate far from the norm, to produce an individual tray in the dental laboratory, which is based on the shape of the jaw and can be adapted accordingly by the dentist.
Prefabricated impression trays, where a particular precision of the impression is important, find their limits. Individual spoons are used for this so that the impression material is applied in the most even layer possible. Uneven layer thicknesses have different setting behavior, which leads to inaccuracies.
They are used to create situational models that record the dental situation in a plaster model before treatment. In the case of dental work that has to be done under time constraints, an individual tray is usually not made, for example when repairing removable dentures. The production of smaller dental work, such as B. single crowns, can be carried out after taking the impression using a prepared spoon.
Prefabricated spoons can be adapted to the anatomical conditions of the patient to a certain extent by means of a palate stop made of silicone material and a distal (rear) dam made of plastic before the impression is taken .
swell
G. Heydecke, total dentures, pretreatment of impressions and model production (PDF; 6.7 MB), University of Hamburg Polyclinic for Prosthetics
Individual evidence
- ^ Hermann Böttger, Horst Gründler, The practice of the telescope system Neuer Merkur Verlag; 2nd edition (1978) ISBN 3-921280-23-0
- ↑ J. Schreinemakers, The Logic in Total Prosthetics , Verlag Die Quintessenz , 1979, ISBN 3876525306
- ↑ Wilm-Gert Esders, Rational work processes in the dental practice, Thieme Verlag, Stuttgart, 2006 ISBN 3-13-132261-6