Notice for Silicone Rubber Mould Taking!
Before making dental restorations, it is necessary to make dental impressions, and then copy the shape of the teeth out of the mouth, which is one of the most important steps in denture production. The precision of the prosthesis is reflected by the impression material. Of course, the more accurate the impression is, the better, because it directly affects the final quality of the prosthesis.


Classification of common impression materials


1. Alginate: The advantage is cheap and easy to operate, but the disadvantage is that it can not accurately reflect the shape of teeth because of its large shrinkage.
2. Agar: Advantage is cheap, disadvantage is easy to break, brittle.
3. Silicone rubber: It has the advantages of high accuracy and stability, and can be used in the manufacture of various prostheses.
In order to ensure the quality of restoration and improve patient satisfaction, doctors are strongly advised to use silicone rubber to take dental moulds for patients.




II. Overview of Silicone Rubber Die Material


Silicone rubber belongs to polymer synthetic rubber and is an irreversible elastic impression material. Its main advantages are:


1. The size is more stable after solidification, and the change of size is about 0.1% within 24 hours.
2. Short operation time, fast coagulation in oral cavity, 3 minutes for the first impression and 3.5 minutes for the second impression.
3. The impression has high accuracy and good operation performance. In addition, the addition silicone rubber impression material is mixed with 1:1 rubber component with the same viscosity, which brings convenience to clinical work.


3. Two-step Mould-taking Operation of Silicone Rubber
IV. Detailed Explanation of Silicone Rubber Moulding Operation


1. Choose a suitable tray for the patient. The tray requires 3-4 mm from the patient's teeth.
2. Clean and dry hands, do not wear latex gloves during operation.
3. Take the first impression
(1) Matrix and catalyst, take one full spoon from maxilla and one flat spoon from mandible to ensure 1:1 of matrix and catalyst;
(2) Use fingertips to mix until the color is uniform without stripes. Knead the mixed first impression into strips and place it on the tray. Then put it in the entrance and take it out after 3 minutes.


(Note: The solidification time of polysilicone rubber is greatly affected by temperature, and it solidifies quickly when the temperature is high.)


4. Repairing the first impression
Use a special dressing knife to remove the inverted concave of the shoulder, gingival papilla and interstitial area of the first impression, repair the spillway, facilitate the second impression positioning and reduce bubbles.


5. Take the second impression
It is suggested to discard the front material 1-50px and place the tray filled with light material in the entrance, slowly and once in place, after curing for about 3 minutes and 30 seconds, the material will be removed from the mouth.




6. Complete and check the impression


(1) The prepared impression has clear and complete subgingival margin, no bubbles and clear and continuous shoulder.
(2) After the impression is removed from the mouth, it is placed for 30 minutes (it can still be used for up to 30 days). Without urgent filling, it can be soaked and disinfected and sent directly to the processing plant.