You know all laboratories live and die by the impression. At PRO-Craft Dental Laboratory, we've been monitoring our remakes and adjustments for many years. We know what impression materials are most successful, and which ones are less successful.
Dental Impression Materials
For example, we know that Impregum and Aquasil deliver the least amount of remakes and adjustments in the labs. Not sure why, but that's been our experience. My only assumption has been that there's something in their manufacturing system that maintains their consistency better than the other materials. So whatever it may be, that's the best guess that we have. And that's our experience with those two materials. One's a polyether and the others are polyvinyl.
Dental Tray Systems
The next most important thing is the tray system. We found that the quad tray from Clinicians Choice is our most successful tray. In fact, we like it so much that we stock some here at the laboratory. We have them available whenever you need them. Contact us online here and we're happy to send you some samples. If you have a question about any of your cases just give us a call at 877-4-THE-LAB (484-3522) and we'll send you a complimentary starter kit and answer all your questions.
Understanding Dental Impression Trays and Materials
Types of Dental Impression Trays
Trays can be fabricated with different materials, allowing dentists to adapt them to the needs of their patients. Commonly, trays are made from plastic and metal for stock trays, while custom trays are typically made from acrylic or shellac.
- Plastic (most common)
- Metal (most common)
- Vinylotermoplast
- Teflon
- Light-curing acrylic
- Self-curing acrylic
Metal trays are considered the most accurate because they are less prone to expansion issues once the impression sets. PRO-Craft recommends the Quad Tray system from Clinicians Choice.
Qualities of Impression Materials
Impression materials should possess certain qualities to be effective:
- Fidelity – Ability to record the finest details.
- Stability – Maintaining the exact shape for a certain amount of time.
- Elasticity – Keeping the fidelity of an impression when removed from the mouth.
- Setting Time
- Sensory Pleasing – Pleasant taste, smell, and color.
- Non-Irritant – Should not be toxic or irritate the mouth.
- Consistent manufacturer quality control.
First Impressions and Final Impressions
Different procedures require different types of impressions. For first impressions, alginate is commonly used. For final impressions that need to show precise details of tissue and tooth structure, materials like polysulfide, fluid silicones, alginate, plaster, waxes, and hard silicones are used.
Alginate is typically available in two different settings:
- Normal Set - Working time of 2 minutes and a setting time of 4 ½ minutes
- Fast Set - Working time of 1 ½ minutes and a setting time of 2 minutes.
Tissue Management
Challenges in obtaining quality impressions often involve adequate tissue retraction and sufficient moisture control. The retraction cord helps to enhance tissue management techniques by delivering the ferric sulfate solutions subgingivally for optimum sulcular fluid control. Ideal tissue displacement occurs within one to three minutes after cord placement. Packing cord placement technique also plays an important role in achieving quality, predictable tissue management.
Expasyl from Acteron is an alternative to the retraction cord. It is a viscous, rigid paste for gingival retraction that not only opens the sulcus but also leaves the field dry and ready for impression taking, cementation, or digital scanning. It is extruded directly into the sulcus where it holds its rigidity to create space between the tooth and the tissue. It can be used for all procedures requiring gingival retraction including impressions, seating of restorations, fitting rubber dams, and restoring class II, III, and V cavities.
The laboratories ability to see the margin as opposed to just trimming to the bottom of the sulcus (not recommended) requires the clinician's impression material to fill the sulcus and go slightly past the margin. The techniques mentioned here will assist in the effort.
Ensuring Dental Impression Material Success
In the end, the tools you choose to work with should benefit you and provide a successful restoration. Being selective and paying attention to the types of trays, the viscosity of impression material, and tissue management along with strict adherence to set times and manufacture instructions will ensure a successful outcome. As always patient satisfaction and the growth of your practice as they share their experience with their friends and families is the ultimate goal.
Find top-quality dental impression materials and trays from PRO-Craft.com. The techniques and materials we utilize to fabricate your restorations are the best in the world and are used by master ceramists worldwide.
Contact us at 877-4-THE-LAB (484-3522) or shoot us a message online and we'll be in touch shortly!
