Ultradent LC Block-Out Resin: Uses and Application Tips

By Ultradent Products, Inc. | Published: 2026-11-03

Category: Návody

Learn how to use light-cured block-out resin for dies and models, with a step-by-step application routine and practical checkpoints to avoid common mistakes.

Quick answer

Use a light-cured block-out resin such as Ultradent LC Block-Out Resin to fill undercuts and voids on dies and models, then cure it fully before proceeding. Apply it in thin increments, keep it exactly where you need it, and check the fit before the next laboratory step.

Why light-cured block-out resin is used on dies

Block-out resin creates a stable base by filling undercuts, voids, and irregularities on a die or model so that subsequent steps have a smooth, predictable surface. A light-cured material gives you working time to place and shape it, then sets on command with a curing light, which helps when you need to build up an area without disturbing the surrounding anatomy.

The main trade-off is that light-cured resin needs adequate light exposure to polymerize fully. If you apply it too thickly or in a hard-to-reach spot, the resin may remain tacky or soft underneath. That is why thin increments and a deliberate curing routine matter more than simply filling the space in one go.

When to choose a different approach

Light-cured block-out resin is not the only option for every undercut. If you are working in a deep or narrow area where the curing light cannot reach, or if the block-out needs to be extremely flowable into a fine crevice, a different material or technique may be more appropriate. The same applies when the die material itself is sensitive to the resin or when the laboratory protocol specifies another product.

Ultradent LC Block-Out Resin is intended for dental professionals. The catalog does not list detailed working time, depth of cure, or compatibility with every die material, so check your laboratory's protocol and the product instructions before using it on a new type of model. When a specification is not provided, treat it as a decision point rather than assuming a value.

Step-by-step application

Clean and inspect the die: Remove debris and release agent residue from the area to be blocked out, then examine the undercut or void under good light. Common mistake: applying resin over contamination, which can prevent it from bonding or sitting flush. If the surface looks glossy or feels slick, clean it again before proceeding.
Isolate the area: Keep the resin confined to the undercut or void. Use a matrix, a separating medium, or careful placement so the material does not spill onto adjacent anatomy that must remain accurate. Common mistake: overfilling and then trying to carve back to the margin. Decide before you apply how you will contain the resin.
Apply in thin increments: Place a small amount of LC Block-Out Resin and adapt it into the undercut with a suitable instrument. Build up gradually rather than placing one large mass. Common mistake: applying a thick blob that cures only on the surface and stays soft underneath. If the area is deep, plan two or more increments with curing between them.
Shape before curing: Once the resin is in place, smooth and shape it to the desired contour before light activation. Remove excess while it is still workable. Common mistake: waiting until after curing to adjust the shape, which can be harder to correct without damaging the die. Check the contour against the planned restoration or appliance before you cure.
Cure thoroughly: Follow the curing light manufacturer's instructions and the resin's instructions for exposure. Keep the light tip close and directed at the resin, and cure each increment. Common mistake: curing from too far away or for too short a time, leaving a tacky surface. If the surface remains tacky after curing, add a thin layer and cure again rather than assuming it is fully set.
Verify the block-out: After curing, check that the undercut is filled, the surface is smooth, and the resin has not encroached on areas that need to remain clear. Test the fit of the restoration or appliance if applicable. Common mistake: skipping the fit check and discovering an interference later. Refine any high spots with a suitable instrument before the next laboratory step.

Product facts

Ultradent™ LC Block-Out Resin: Ultradent LC Block-Out Resin is a light-cured resin designed for dental professionals who need a resin that stays where it is placed. A resin that holds its position helps you block out undercuts and voids without it flowing away before you cure it.
Ultradent™ LC Block-Out Resin