ABO Retention and Stability Flashcards

Bonded retainers should be checked at recall visits primarily for:

Answer: Bond failures, wire distortion, and signs of plaque accumulation

Bonded retainer recall includes checking bond integrity, wire distortion, and periodontal health since fixed wires can accumulate plaque.

Essix (vacuum-formed) retainers are contraindicated in patients who:

Answer: Exhibit bruxism or severe parafunction

Patients with bruxism can rapidly wear through or fracture vacuum-formed retainers, reducing their effectiveness and potentially damaging dentition.

Long-term stability of corrected Class III malocclusion treated with growth modification is LEAST favorable in patients with:

Answer: Vertical mandibular growth pattern and strong Class III genetics

A vertical growth pattern combined with strong Class III genetic tendency produces the highest risk of relapse after orthopedic correction.

The primary purpose of a positioner appliance at the end of fixed treatment is to:

Answer: Seat and refine the occlusion while providing initial retention

Positioners use a flexible rubber or silicone tray to detail and seat the occlusion while simultaneously acting as a short-term retainer.

According to the ABO grading system, which OGS (Objective Grading System) criterion evaluates the axial inclination of posterior teeth?

Answer: Root angulation

The ABO OGS root angulation criterion evaluates whether roots are properly parallel and properly angulated on the final panoramic radiograph.

Retention protocol for a patient treated for a severe anterior open bite should ideally include:

Answer: Long-term or indefinite retention, often with a fixed retainer

Anterior open bites are among the least stable corrections in orthodontics, requiring long-term or permanent retention to prevent relapse.