1. What is the major difference in the ERA? Connection point inside (this word should be in bold type) the root.Intraradicular ball and socket joint.
2. Is there an advantage to this? Teeth with poor crown to root ratios can be used as attachment abutments for an overdenture when periodontal conditions permit. Intraradicular connection of attachment components lowers occlusal stress on the root. Cases in which marginally adequate abutments do not warrant the expense of using of a cast root cap coping.
3. Are there sizes to be concerned with? The Stern Root Anchor retains and stabilizes complete overdentures and removable partial dentures using the retained roots of endodontically treated teeth. It has a minimal crown to root ratio because the attachment places the point of occlusal force application within the root. White for standard female and mini female, Orange for standard female, Grey for standard female, Blue for standard female.
4. Is preparation difficult? Technique using one-step carbide drills: Complete endodontic procedures. Reduce the tooth to slightly above the gingival level.Use the appropriate Stern Root Anchor drill (standard or mini) to form a retention site in the occlusal surface of the root for cementation of the attachment female. Use low speed rotation and copious application of cooling water while cutting. Cut to the full depth of the bur, creating an occlusal seat for the attachment female. The drill has a built in stop to prevent over drilling. The female should be placed with its long axis within 5° of parallel to the denture's path of insertion. It need not follow the root canal. When the root is at a significant angle to the path of insertion consider the possibility of root wall perforation. Either use the mini size female, or forgo use of the Stern Root Anchor. The Stern ERA Direct Placement Overdenture Attachment, for example, could be substituted because it requires less root preparation and can accommodate highly divergent abutments. Alternative Instrumentation for Standard and Mini Female Site Preparation Specialized diamond burs are available for shaping a prepared site for the standard female and the mini female.
5. How is the female held in the preparation? Cement the female into place, again using the male as a handle. Be sure the male is fully seated in the female with the centering collar covering the female opening. This is to prevent any excess cement from entering the female. ERA Lock composite resin cement works well in this application.
6. Are there special home care instructions for the patient? Daily Maintenance by the Patient Exposed dentine at the occlusal surface of the abutment root should be treated daily with water free, 0.4% stannous fluoride gel for protection against decalcification and secondary caries. All exposed root surfaces should be protected whether or not the roots support attachments. Do not use gel, which has passed its expiration date. Black collar males used with standard females. Universal hinge. Intraradicular ball and socket joint. Nylon male, titanium female. Lightest to strongest: white, orange, grey. Standard and mini size. Fixation: Male - polymerized into denture acrylic. Female - cemented directly in root preparation. Three color coded males for three levels of retention. White collar males used with mini females.
