Custum tray and abutment tray

What's custum tray ?
It is a tray for obtaining an accurate impression. It is a tray that has a fixed space for the dentition and the alveolar ridge. Manufactured by a dental technician using an immediate polymerization resin.
When using a silicone impression material, the inner surface is mechanically roughened.
When using an alginate impression material, an infinite number of holes are made in the tray.
What's abutment tray ?
The monodental tray is a tray for impressing the abutment teeth in units of one tooth for the purpose of preventing deformation of the impression. The advantage is to improve the dimensional accuracy by making the thickness of the impression material a uniform thin layer. Gingival retraction can be performed simultaneously with the impression. Cut off the effect of undercutting of adjacent teeth. Etc. It is manufactured on a model with an immediate polymerization resin, and it is used after correcting the margin in the oral cavity. Materials
Paraffin wax, immediate polymerization resin, tray resin (immediate polymerization resin), gauze, technical bar (multi-pad).
Methods1. Abutment tooth formation is ideally performed on the model.
2. Make a spacer with paraffin wax.
3. Apply a separation material (Vaseline) and press-fit the immediate polymerization resin.
4. Once the resin is cured, make the shape correction with a bar.
5. The handle is made of resin and the inside is further roughened.