Implant Design & Fabrication Flashcards

When using guided bone regeneration (GBR) membranes in conjunction with implant placement, which membrane type maintains space the longest without premature collapse?

Answer: Non-resorbable dense PTFE (d-PTFE) membrane

Non-resorbable dense PTFE membranes maintain rigid space for the full healing period without degradation, making them ideal for large defects requiring long-term space maintenance.

A CAD/CAM-designed implant surgical guide is classified as 'tooth-supported,' 'bone-supported,' or 'mucosa-supported' based on:

Answer: Which anatomical structure provides the guide's positional stability during surgery

Surgical guide classification describes the anatomical reference surface — remaining teeth, exposed bone, or soft tissue — that stabilizes the guide intraoperatively.

In implant fabrication, 'cold working' of titanium alloy (Ti-6Al-4V) during machining can induce which problematic microstructural change?

Answer: Residual compressive or tensile stresses that affect fatigue resistance

Machining introduces residual stresses in the titanium that can either improve (compressive) or compromise (tensile) fatigue life, requiring careful manufacturing process control.

The 'switching platform' design advantage is most clinically significant for patients with which soft tissue biotype?

Answer: Thin scalloped biotype at risk for peri-implant bone loss and tissue recession

Platform switching is most beneficial in thin biotype patients where even minimal crestal bone loss translates to visible soft tissue recession and esthetic compromise.

Which implant body geometry is specifically designed to convert lateral bone expansion forces into compressive forces that improve primary stability in low-density (D3/D4) bone?

Answer: Tapered body with condensing threads increasing in pitch from apex to collar

A tapered body with condensing thread geometry compresses trabecular bone laterally as the implant advances, increasing bone density and primary stability in soft bone.

When fabricating a screw-retained implant crown, the access hole for the retaining screw is ideally positioned at which location on the occlusal/incisal surface?

Answer: Through the cingulum (anterior) or central fossa (posterior) aligned with the implant axis

The screw access hole must align with the implant long axis; ideal placement is through the cingulum of anterior teeth or central fossa of posteriors to minimize structural compromise.

ISO 14801 is the standard used to evaluate which performance characteristic of dental implants during the regulatory approval process?

Answer: Fatigue resistance under dynamic cyclic loading conditions

ISO 14801 defines the dynamic fatigue test protocol for endosseous dental implants, applying cyclic loads to determine fatigue limit and ensure mechanical safety under simulated function.