Sterngold offers a variety of both precision (metal) and semi-precision (plastic) dental attachments for use with segmented fixed bridgework. Your choice will be based on your experience, knowledge, and skill level. Unfortunately, many inexperienced people choose the cheaper plastic semi-precison attachments. These often take more time and more skill to obtain a suitable result. You may do better to pay a little more for the precision attachment and spend less time to create a more accurate prosthesis.

Major applications of segmentation are: non-parallel abutments, easier laboratory fabrication and clinical insertion of large fixed restorations, occlusal force management in pier abutment cases, and segment removal for case repair or conversion to a removable partial denture.

Proper Measurements for Attachments

Sterngold works hard to make using attachments easy for you. In this catalog, we provide our best advice on space requirements based on extensive practical experience.

Each attachment description lists the minimum space required for placement of the attachment, to assure a high rate of success and long-term function. Allowance is already made for restorative materials, such as dental casting alloys or denture acrylic, surrounding and holding the attachment component. With this information you can measure a study cast and decide if an attachment can be used in the available space.

These allowances are:

• Denture acrylic thickness occlusal to extracoronal attachment components, bars and overdenture attachments (influences Height), 1mm

• Denture acrylic thickness lateral to attachment components (influences Removable Component Width), 1mm on each side.

• Casting alloy thickness between a box preparation axial wall and a metal, intracoronal, precision attachment female (influences Prep Depth), 0.4mm

• Casting alloy thickness for root cap coping (influences Height), 0.5mm.

Working with Metal Attachments

Depending on the attachment's design, metal components are anchored in denture acrylic, soldered to a casting, or invested along with a wax pattern and cast against with a dental alloy. Use an alloy with a casting temperature at least 100°F (40°C) below the lowest value of the component's melting range when casting against an attachment component.

Melting Ranges of Attachments

Ceramacast components
Degrees F: 2600-2760
Degrees C: 1425-1515

Ceramicor components
Degrees F: 2550-2715
Degrees C: 1400-1490

Doral components
Degrees F: 1705-1860
Degrees C: 930-1015

Elitor components
Degrees F: 1615-1725
Degrees C: 880-940

Iridium-platinum components
Degrees F: 3300-3360
Degrees C: 1820-1850

NPS components
Degrees F: 2700-2850
Degrees C: 1480-1565

OSV components
Degrees F: 1885-2010
Degrees C: 1030-1100