Which cases are good candidates for Apex Flex, and what preparation is required?
Apex Flex is indicated for tooth-supported partial dentures. Retention comes from flexible clasp arms engaging natural undercuts rather than from rigid rests and cast retainers, so case selection should center on sound, well-supported abutments and a passive path of insertion.
Published applications
| Application | Notes |
|---|---|
| Tooth-supported partial dentures | The primary indication |
| Anterior esthetic partial replacement | Where visible metal clasping is unacceptable |
| Unilateral partial replacement | Single-side edentulous spans |
| Transitional partials during implant integration | Interim function and esthetics during healing |
| Replacement of a lost or fractured existing partial | Often faster when a digital file is already archived |
| Metal or acrylic monomer sensitivity | Metal-free and biocompatible construction |
Tooth preparation
One of the practical advantages of Apex Flex is how little preparation most cases require.
- Minimal to no preparation is required in most cases.
- Optional rest seats where vertical support is indicated.
- Optional enameloplasty of severe undercuts blocking a passive path of insertion.
Because retention depends on the material flexing over the height of contour, undercut detail in your scan is critical. Avoid over-smoothing tissue during scanning or scan processing, since loss of undercut detail directly compromises retention. Broad, well-captured undercuts retain better than aggressive localized ones.
Design considerations
When ROE's design team builds the case, several principles govern a durable flexible partial:
- Controlled saddle thickness, typically in the range of 1.5 to 2.0 mm.
- Relief over frena and in areas of movable mucosa to prevent ulceration and edge roll.
- Rounded internal transitions throughout the design, which reduce stress concentration and improve long-term flexural durability.
- Strategic placement of flexible clasp zones so retention is maximized without over-flexing the clasp arms.
When to consider a different ROE partial
Flexible bases do not provide the cross-arch rigidity of a cast framework, and rest seat preparation is not a substitute for rigid support. If a case demands significant rigidity, long distal extensions with heavy functional loading, or cross-arch stabilization, one of ROE's rigid or hybrid options may serve the patient better. ROE's Certified Dental Technicians can help you evaluate borderline cases and design clasping before you commit.
| ROE partial option | Esthetics | Strength | Lab days | Key benefit |
|---|---|---|---|---|
| SLM Cobalt Chrome | ★★★ | ★★★★ | 12 | High strength and durability |
| SLM Titanium | ★★★★ | ★★★★★ | 13 | Best biocompatibility, high strength |
| Acetal | ★★★★★ | ★★★ | 12 | Alternative for material allergies |
| Thermoplastic | ★★★★★ | ★★★★★ | 8 | Flexible with added comfort |
| Thermoplastic Hybrid | ★★★★ | ★★★★★ | 12 | Flexibility plus framework strength |
An All-Acrylic (Flipper) Partial is also available at 5 lab days as a lightweight, economical interim option.
Additional Resources
For more information concerning the LOCATOR Overdenture:
Contact Information
For help with a solution for your next case, contact ROE Dental Laboratory:
- Phone: (216) 663-2233
- Email: info@roedentallab.com