Inside Dental Technology
September 2011, Volume 2, Issue 8
Published by AEGIS Communications
Directional Insight on Implant Attachment Solutions
Using Rhein83’s guidelines and steps, many implant attachment issues can be resolved.
By Dennis Urban, CDT
Today’s attachment and implant market can be confusing and overwhelming, ideally pertaining to cases that involve divergence issues and limitations on occlusal space. Poor placement of implants is an everyday occurrence in the world of dentistry and, most of the time, the stress and responsibility is placed on the dental technician to come up with solutions. This is exactly why communication is key between the dentist, periodontist, oral surgeon, and dental technician.
According to the American Dental Association, one implant survey shows that 1.5 million dental implants were placed in a recent year and that number continues to grow. Bone quality and bone volume are essential to a successful implant’s long-term outcome. A clinically mobile implant is considered a failure. While early implant failures denote a lack of integration, divergence issues can also result in improper loading and clinical failure.
Fortunately, there are solutions to divergence issues. The Sphero Flex and Sphero Block attachment systems by Rhein83 can provide excellent results in compromised divergency situations. Sphero Flex can restore non-parallel implants with up to 43º of divergency. It has a 2.5-mm sphere, inclines 7.5º in all directions, and is considered “self-parallelizing.” The directional rings ensure passive insertion and reduce trauma to implants. The Sphero Block is a stationary ball abutment and can correct divergence up to 28º. The Sphero Flex and the Sphero Block are both customized to fit any implant. When space is a concern, the Sphero Block abutment can be ordered with a 1.8-mm or 2.5-mm sphere and is used with an elastic retentive cap.
The directional ring is chosen on the basis of the position of the implant. When the implants are parallel, the 0º ring is used. Upon the degree of divergence from the line of parallelism, apply a 7º or 14º ring. The reduction or elimination of off-axis stress on a divergent implant can make a world of difference on the success of the implant and the overdenture. Some roadblocks that could be faced when divergence on implant placement becomes an issue are path of insertion from the implant overdenture, compromised room for denture teeth, occlusal scheme limitations, and inadequate strength of the implant overdenture due to lack of room for denture base material.
The feedback from dentists who have delivered cases when the Rhein83 Sphero Flex and Sphero Block was used correctly in appropriate situations has been extremely positive. The bonus to this system is the elastic retentive cap. Using elastic retention, the function of Rhein83 attachments is extended. An example of processing the elastic caps intraorally can be seen in Figure 1, Figure 2, Figure 3, Figure 4, Figure 5, Figure 6.
Because these caps are so elastic, it is possible to control the flexure. The result is a resilient and shock-absorbing prosthesis. The resilience can be controlled due to the assortment of available retentive caps and their various elastic characteristics. The volume of the retentive area is increased because of the elastic memory or the cap (Table 1).
When curing elastic caps with directional rings on the model, a simple procedure is followed similar to the intraoral method. Keep in mind that prefabricated stainless-steel housings can be used; in fact, using these housings makes it much easier to change the caps. First screw the abutment on the model, then place the directional rings and rotate them until optimal parallelism is achieved. Lastly, place the elastic caps on the sphere and process with cold cure acrylic.
There are cases when divergence issues are too extreme and require the removal of the implant. But when the degree of divergency falls within the guidelines and parameters of Sphero Block and Sphero Flex, functional results and long-term success are both achieved.
The manufacturer provided the preceding material. 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.
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About the Author
Dennis Urban, CDT, has worked in dental technology for 35 years and was the recipient of the 2007 NADL Excellence in Education award. He is currently the Technical Consultant and Removable Manager for Drake Precision Dental Laboratory in Charlotte, North Carolina.