BAOT Dental Porcelain Dentin

 

The production of porcelain teeth is a high-tech treatment project. To make a high-quality porcelain tooth, it must go through strict design, accurate color comparison, precise tooth preparation, careful gum protection, high-precision impression, perfect temporary crown production, qualified crown bonding, fine blending, and polishing steps, neglecting any of these steps will result in a decline in the quality of the porcelain crown.

 

In the process of making dental porcelain teeth, the failure of the restoration and the rework accounted for a large proportion due to the lack of tightness of the edges and high occlusal.

Let’s see how to avoid the problems.

 

 

1. Porcelain crowns are not fully seated

 

  - Clinical Side

 

① The problem with the doctor’s tooth preparation, such as the abutment is not smooth and has a fulcrum, the preparation of the shoulder is irregular, and the common positioning path has a slight deviation;

 

Solution: It is recommended to pay attention to smoothness during clinical tooth preparation, regular shoulder preparation, and consistent positioning path.

 

② The moisture ratio of the gypsum is not adjusted according to the instructions in the instructions, resulting in an inappropriate expansion coefficient, and the edge will be different from the actual neck edge;

 

Solution: The moisture ratio of gypsum should be adjusted strictly according to the instructions.

 

③ Two kinds of gypsum are used to cast the model. The first layer of gypsum is super hard plaster, and the second layer is anhydrite or ordinary gypsum. The shrinkage of the two layers of gypsum is inconsistent in this example, which will lead to a slight change in the common seating path of the bridge;

 

Solution: The same plaster should be used to cast the model.

 

④ It is not a model filled with super anhydrite, and the general anhydrite replica model will have some errors;

 

Solution: It is best to use the super-hard paste to fill the model.

 

⑤ After the impression was taken, the model was not poured in time, and the impression material had a slight shrinkage, which caused some deviations in the plaster model.

 

Solution: After taking the model, the technician will fill the model.

 

  - Technician Side

 

① When making the model, the rest of it is inaccurate, and there is a gap between the die and the base, resulting in a high occlusal height of the porcelain teeth and poor edge sealing.

 

② The die shakes, and there is a slight change in the common seating path.

 

Pay attention to whether the type nails are glued firmly, and whether the type nails are consistent;

 

Whether the hardness of the gypsum of the filling base is appropriate, and whether the moisture ratio is correct;

 

If it is a nail set, pay attention to whether the set and the nail are very close and whether the tightness is appropriate.

 

③ The contact points of the adjacent teeth are worn away during the mold cutting and the shape modification of the porcelain teeth. When the doctor wears the teeth, a fulcrum will be formed and cannot be fully seated.

 

2. The edge is not fully seated against the gum line

 

  - Clinical Side

 

① There is no gingival retraction, and no silicone mold is used.

 

If the gum retraction line cannot enter the periodontal, you can use gum retraction paste;

 

If there is no silica gel, you can use cold weather materials and alginate materials to take impressions;

 

Doctors must pay attention to the fact that gingival retraction and precise impression materials must be used together, otherwise, it will be difficult to achieve a precise fit of the edges of the porcelain teeth.

 

② The moisture ratio of the model gypsum is not adjusted according to the instructions in the instructions, resulting in an inappropriate expansion coefficient, and the edge will be different from the actual neck edge.

 

③ It is not a model filled with super anhydrite, and the general anhydrite replica model will have some errors.

 

④ When pouring the model, there are air bubbles at the edge of the neck.

 

⑤ Before casting the model, the saliva and blood in the impression were not cleaned.

 

  - Technician Side

 

① There is an error in the trimming of the neck margin, and the neck margin is extended too long.

 

② The neck margin was damaged when the model was cut.

 

③ The neck margin was damaged during waxing.

 

④ The edge was damaged when caring for gold and porcelain.

 

 

3. High occlusion

 

  - Clinical Side

 

① Doctors use wax and embankment, the wax itself will have errors, and the probability of deformation during the transportation is very high. It is recommended to use silica gel as the joint embankment, use the red paste as the embankment, or put the biting wax in a hard box to prevent deformation during transportation, which can reduce the error of occlusion.

 

② The doctor did not wear a temporary crown to the patient, resulting in the elongation of the abutment teeth.

 

③ Some doctors take a partial model, and the occlusion will have some errors. It is best to take the whole model.

 

④ The opposite jaw model is not made of anhydrite. Ordinary gypsum is easy to be worn and is not accurate.

 

  - Technician Side

 

① The occlusal judgment is wrong, and the occlusal relationship transfer is incorrect.

 

② The matching model is worn during grinding.

 

③ It is best to use a precision frame if the judgment of the lateral jaw is inaccurate.