Production of a bis-acrylic temporary
No matter how a provisional crown or bridge is produced, it needs to be designed for optimal conditioning of the soft tissues. This is a relevant aspect for implant- and tooth-based restorations with subgingival margins. In this case, the soft tissue usually needs time to recover from tooth preparation, and ideal tissue management with the aid of the temporary will ensure easier exposure of the margins during impression taking and the desired dry, clean working field during cementation of the final prosthetic work.
Whenever teeth with a pre-existing anatomy need to be restored, chairside matrix production is usually possible. A preliminary impression is taken, filled with bis-acrylic resin and placed in the patient’s mouth to obtain the desired shape of the temporary. The process is completed with careful adjustments especially in the area of the restoration margin. With some materials like 3M™ Protemp™ Plus OR Protemp™ 4 Temporization Material, the restorations’ surfaces become glossy just by wiping with ethanol.
Case example: Initial clinical situation with a PFM crown on the second premolar that needs to be replaced.
Clinical situation after crown removal and tooth preparation.
Removal of the undercuts in the area of the crown margin in the preliminary impression
Matrix ready to be filled with bis-acrylic temporization material.
Temporary in the matrix after setting in the mouth (3M™ Protemp™ Plus Temporization Material).
Temporary taken from the matrix.
Removal of the excess bis-acrylic resin with a fine-grained diamond instrument.
Careful finishing and smoothening of the margin.
The smear layer on the surface is easily wiped off with ethanol, leading to a glossy appearance.
Cementation of the provisional crown with temporary cement.
Temporary in place.
In implant cases or other situations without pre-existing tooth anatomy, the matrix is usually manufactured in the dental laboratory. Here, the tooth anatomy is built up on a model and the matrix is produced e.g. by thermoforming. The subsequent procedure steps are the same as for the chairside procedure.
Edentulous maxilla with four implants in place.
Lab-produced
Lab-produced matrix.
Matrix filled with bis-acrylic material (3M™ Protemp™ Plus Temporization Material), placed in the patient’s mouth.
Basal view of the implant-based temporary with smooth surfaces and rounded edges.
