Inside Dental Technology
April 2013, Volume 4, Issue 4
Published by AEGIS Communications
Predictable Casting for Full Arch Splinted Implant Frameworks
Produce high quality castings with the Neo Super Cascom
Casting metal alloys by the lost wax process has been recognized in the industry for many years. It is known that in order for the quality of dental cast restorations to be improved, having alloys with the proper composition is not enough. Biocompatibility, good mechanical and physical properties, longevity of the restoration, compatibility with porcelain, and most importantly, casting techniques, are each pivotal as well.
Casting metals is not without much difficulty. There are many areas of the casting process where problems may arise. These problems may include castings that are incomplete, rough, too tight, too loose, or porous.
Laboratories worldwide still use the centrifugal casting method, which requires specialized training, experience, and skills to minimize miscasts and produce high quality castings. The introduction of the Neo Super Cascom from KDF US, Inc, which features automated technology, has simplified the casting process so that laboratory technicians can produce high quality castings efficiently and predictably.
Casting porosity is a common issue encountered in the laboratory, which has several potential causes including excessive burnout and casting temperature. With the Neo Super Cascom, a spiral ceramic heating element completely surrounds the crucible and allows uniform heating of the alloy with precise temperature control. The advantage to this method is that casting can be performed at the lowest possible temperature, reducing the risk of porosity in the casting.
Fit of the restoration is dependent on many variables (Figure 1 and Figure 2). The casting process is one part that has a significant impact. Laboratory technicians have struggled with large castings over the years and, as a result of the inaccuracy inherent in the casting process, have chosen to cast a large framework in multiple pieces and use soldering to finalize a large splinted framework.
Castings that are rough or incomplete are frustrating for the technician from both a time and cost perspective. Miscasts most commonly occur due to insufficient force. However, miscasts can also be the result of excessive force due to mold gas back-pressure. With conventional centrifugal casting methods, pressure is applied from one direction only. However, the Neo Super Cascom design includes an airtight chamber design, allowing casting pressure to be applied from all directions. It also uses an inverted chamber casting method which decreases the risk of miscasts by minimizing the contact of the casting alloy with the atmosphere prior to entering the casting ring. The maximum melting capacity is up to 150 gm, which allows for larger castings. These modifications ultimately result in a complete casting with superior clarity, ultimately resulting in superior fit and reduced chairtime.
Two methods of programming are provided. One is an auto program mode, and the other is a manual mode. The unit has the ability to memorize up to 100 programs. Once the start temperature is reached, the crucible is placed into the muffle and the melting process is started. The temperature will heat up towards the casting temperature. After complete melting is confirmed, the operator must choose the type of pressure for casting. This may be either compressed air or Argon gas. A casting ring is placed on top of the muffle, the chamber lid is closed, and the arm is locked. The casting is now activated. Vacuum is created in the chamber, and once the vacuum level is reached the chamber will invert to apply pressure automatically. After a cooling period, the chamber returns to its original position automatically (Figure 3 through Figure 5).
The Neo Super Cascom casting machine provides the dental technician with the ability to produce high quality castings with a variety of materials, including silver, gold, precious, semi-precious, nickel chrome, and cobalt chrome, in an automated fashion. Its large melting capacity of 5 ounces allows for the production of larger castings with efficiency and predictability (Figure 6 through Figure 10).
About the authors
Domenico Cascione is the CEO of OperArt LLC; Saj Jivraj, DDS, MS.Ed, is a Prosthodontist and has a private practice limited to prosthodontics and implant dentistry in Oxnard, California; and DaYoung Song, CDT, is a dental technician in Los Angeles, California.
For more information, contact:
Disclaimer: The preceding material was provided by the manufacturer. The statements and opinions contained therein are solely those of the manufacturer and not of the editors, publisher, or the Editorial Board of Inside Dental Technology.