QUAD-TRAY Xtreme: Eliminate Flex for Consistently Accurate Impressions
The dual-arch impression technique offers many benefits for single-tooth impressions. It impresses the preparation site, impresses the opposing arch, and registers the bite all at once. It can be used for more than one preparation, and it is more economical than taking a full-arch impression with polyvinyl siloxane (PVS) combined with a separate impression of the opposing arch and separate bite registration. In addition, the dual-arch technique takes less chairtime and is easier for the patient.
The Problem: Impression Distortion
Many dual-arch trays are plastic, compromising accuracy when these trays flex as the impression is taken, resulting in discrepancies of 180 ?m to 210 ?m. This flex can be caused by the high side walls of the trays hitting the palatal tissues, maxillary tuberosities, or tori present in the oral cavity. The very act of swallowing during the impression can cause the tongue to displace the lingual wall of the tray during polymerization, creating distortion. As well, the thicker rheology of high-viscosity impression materials can cause the plastic tray to flex away from the tooth preparation.
When the tray is removed, the plastic memory of the tray creates an inward pressure, and depending on the stiffness of the heavy body used, the dies can be distorted mesiodistally, creating problems with marginal fit and interproximal contact.
The Solution: QUAD-TRAY Xtreme
The best solution is to use a metal tray, which eliminates flex. The QUADTRAY Xtreme from Clinician?s Choice is designed to complement the dual-arch impression technique, eliminating the distortion common with plastic dual-arch trays. Because the tray is fabricated from aluminum, it has no elastic memory to create distortion. The low sidewalls cannot cause distortion from axial roll or outward flex, and the design incorporates an adjustable wide arch and thin retromolar area. When combined with the correct stiff heavy body PVS material, the impression is dimensionally accurate and stable for an indefinite period.
A new addition to the QUAD-TRAY family is the QUAD-TRAY XL, which provides the same benefits as QUADTRAY Xtreme but in a full-quadrant design. It extends to the dental midline, has a perforated, tapered buccal/facial wall and a slotted lingual wall that helps lock in the impression material without impinging on the palate. With the QUAD-TRAY XL, clinicians can provide the laboratory with more information for precision and accuracy in creating crown-and-bridge prostheses.
Save Time and Money
Laboratories see far too many plastic trays with obvious burn-through of hard or soft tissues, reflecting a probable distortion, but the fear of losing clients often dissuades them from returning the case for a new impression. What the laboratories cannot see is the possible mesiodistal discrepancies caused by memory flex of the plastic tray.
In an era where economic turmoil is a reality, neither the laboratory nor the clinician can afford the time, frustration, the cost of remakes or the time taken to ?adapt? an ill-fitting prosthesis.