Tasks for independent work during preparation to practical classes.

Ministry of Public Health of Ukraine

Higher State Educational Establishment of Ukraine

"Ukrainian Medical Stomatological Academy"

"Approved"

at the meeting of the department

propedeutics of Prosthodontics

Head of the department

Associate Professor, Korol D.M. _________

"_____"_______________ 20___

RECOMMENDATIONS

FOR STUDENTS’ independent WORK

during the preparation to practical classes

Poltava 2011

1. Actuality of the theme:

Analysis of the literature indicates that the leading place in removable prosthetics take partial removable laminar dentures However, their manufacturing is time-consuming and complex process that requires from the medical and dental technician specialized professional approach to all clinical and laboratory stages of their manufacturing and rational grounded application of the basic and auxiliary materials. It is known that for manufacturing of various designs of dentures is necessary to obtain a high-quality impressions and patterns. With a wide range of impression material, you need to know their composition and properties to choose the one that best of all fits the stated objectives of orthopedic treatment. Manipulation of obtaining an impression and a model is a clinical task on the quality of which depends the success of orthopedic surgery.

2.Specific objectives:
- To justify the choice of impression materials in different clinical conditions in manufacturing of removable partial plate prosthesis.
- Propose to understand the sequence of actions in obtaining a working impression.
- Propose to understand the sequence of actions in obtaining a working model.
- Classify impression materials used in prosthetic dentistry.
- To explain the positive and negative properties of impression materials.
- To analyze the quality of the received impression.

3.Base level of training:

Tasks for independent work during preparation to practical classes.

4.1. Recommendations for students’ independent work and album for independent work of students.

4.2 Theoretical questions to the lesson:

1. Indicationsis to all removable partial dentures fabrication.

2. Contra-indication is to all removable partial dentures fabrication.

3. Components of all removable partial dentures.

4. Clinical stages of all removable partial dentures fabrication.

5. Laboratory stages of all removable partial dentures fabrication.

6. Positive and negative properties of all removable partial dentures.

7. Definition of the impression.

8. Classification of the impressions.

9. Definition of the casts. Steps of cast making.

4.3. Practical works (tasks) that are executed at the lesson:

By means of diagnostic models, thematic patients demonstratively examined students:

1. indication and contra-indication to all removable partial dentures fabrication.

2. sequence and maintenance of the clinical stages of all removable partial dentures fabrication.

3. sequence and maintenance of the laboratory stages of all removable partial dentures fabrication.

4. Take impression

5. make cast

Content of the theme:

Impressions and models making.

Classification of the impressions by Gavrilov

1 group - 2 group -

Preliminary Final

Anatomical Functional

Full, Pressure techniques ( mucocomressive)

Partial Selective pressure

Bite registration Minimal pressure

No Pressure ( mucostatic)

Anatomical impressions leave out of account mobility of mucous membrane and are made by using stock impression tray. Functional impressions take into account mobility of mucous membrane and are made by using special tray. The aim of the functional impression is to maximize the rest area of the denture base taking the muscle movements into consideration.

Impression trays

Impression tray

A receptacle or device used to carry the impression material to the mouth, confine the material in apposition to the surfaces to be recorded, and control the impression material while it sets to Form the impression.

There are two types of impression trays:

1. Stock impression tray

2. “custom” impression tray (also be called “special” or “individual” trays).

Stock impression trays

Stock trays come in a variety of designs and sizes. These trays fall into three main types:

Full dentate trays
partially dentate trays
edentulous trays

There are a variety of sizes to suit most patients. Stock trays can be made of metal (not disposable) or plastic. The plastic trays are intended to be disposable.

Advantages (metal stock trays)

• designed to be used many times
• must be able to be srerilised
• used to take first impression for the production of The primary cast

Disadvantages

• the problem in using stock trays is that the impression material is of various thickness which can lead to distortion
• the flow of the impression material cannot be guaranteed to cover all the areas of the teeth or tissues required
• pressure points can occur when using a stock tray. The patient can experience discomfort during impression taking due to the large amount of impression material used in the tray. In order to overcome these problems a special tray should be constructed.

Impression tray consists of body, handle and flanges. Upper impression trays have a palatal section; which is, of course, absent in lower trays. Very often it is not possible to obtain an accurate impression with a standard tray. In such cases a model obtained from the first impression is used to make a special tray. With this “made to measure” individual tray perfectly accurate final impression can be taken.

Date: 2015-12-24; view: 1077