Try-In & Fit Check — OCTOdent Protocol

Why this page exists

A printed restoration passes through three evaluations before it goes to cementation: visual QC after post-cure, fit verification in the patient's mouth at try-in, and occlusal check before final cure. Skip or rush any of them and you cement a problem.

This page documents the try-in protocol OCTOdent recommends for every OCTOpod-printed restoration — the checks, the tolerances, and what to do when something doesn't pass.

The protocol at a glance

  1. Pre-try-in inspection on the bench: margins, intaglio, external surfaces. Reject and reprint anything that fails.
  2. Dry try-in first: seat the restoration without cement, verify fit and contacts.
  3. Handle from the occlusal only — never touch the intaglio with bare gloves or contaminated instruments after try-in begins.
  4. Check margins under loupes or operatory scanner.
  5. Check contacts with unwaxed floss.
  6. Check occlusion with articulating paper in CR and excursive movements.
  7. Decontaminate the intaglio with Ivoclean (20 sec) if saliva contacted it during try-in.
  8. Dry with oil-free air before proceeding to cementation.

If any check fails irreparably — reprint. Don't compromise.

Step 1 — Bench inspection

Before the restoration goes near the patient's mouth, inspect it under operatory light or loupes.

What passes

  • Margins are clean and continuous. No chips. No flashing. No visible delamination.
  • Intaglio surface shows print layer lines (the horizontal banding typical of SLA/DLP prints). Glossy or smooth intaglios indicate residual uncured resin — go back to the post-processing protocol.
  • Color and opacity match the shade printed. No white haze, no patchy translucency.
  • Support stubs are finished flush with no overhang or undercut at functional surfaces.

What fails (and means re-print)

  • Chipped margin — printed resin is not repairable with flow composite to clinical marginal fit.
  • Delamination between print layers — structural failure, not a fit issue. Reprint.
  • Distorted geometry (warped from the design) — orientation / support structure let the part relax during cure. Reprint with better orientation.
  • Obvious polymerization deficit (tacky, soft, deformable under gentle pressure) — re-post-cure first. If still deficient, reprint.

Step 2 — Dry try-in

Always try-in without cement first. Seating a restoration full of cement before verifying fit leads to exactly one outcome: premature set with a restoration that doesn't seat. You then chip cured cement off the internal surfaces and compromise the retention surface.

Technique

  1. Remove the temporary (if any) with a hemostat or crown remover. Clean the prepared tooth with pumice and rinse.
  2. Isolate with cotton rolls (rubber dam goes on before cementation, not usually before try-in — the dam can complicate contact verification).
  3. Seat the restoration with firm finger pressure. It should fully seat without rocking.
  4. If the restoration seats fully on first attempt — good. Proceed to margin / contact / occlusal checks.
  5. If it doesn't seat — diagnose before forcing. Binding contacts, interproximal over-contours, or an internal high spot are typical culprits.

Handle from the occlusal only

From this step forward, do not touch the intaglio with ungloved fingers, contaminated instruments, or bite-block material. Any oil, blood, or saliva on the intaglio contaminates the bonding surface. Handle the restoration by the occlusal/external surfaces only.

Step 3 — Margin check

Under loupes (4–6× minimum) or an operatory scanner:

  • Marginal fit should be continuous and close — no visible gap at the preparation margin.
  • No rocking — press alternately on opposing cusps; the restoration should not see-saw.
  • No vertical step at the margin — the restoration margin should be flush with the tooth, not over-contoured or under-contoured.
  • Emergence profile follows the tooth anatomy — no sharp ledge or sudden width change.

Acceptable tolerances

  • Marginal gap: <100 μm is ideal; <200 μm is clinically acceptable for printed resin; >200 μm is an adjust-or-reprint decision.
  • Seating completeness: the restoration should fully seat without any visible lift-off. Partial seating is never acceptable.

If the margin fails

  • Small binding high spot (you can see where it's pressing): adjust with a fine diamond at low speed on the intaglio at the high spot location. Rinse, re-try. Adjust sparingly — aggressive intaglio adjustment invalidates the fit.
  • Over-contoured margin: adjust external surface with a fine football/pear bur at low speed.
  • Generalized poor fit (no obvious high spot; restoration just doesn't seat): this is a scan error, a design error, or a distortion during print. Reprint after fixing the upstream cause.

Step 4 — Contact check

Use unwaxed floss, single strand, through each proximal contact.

Pass criteria

  • Floss passes through with light resistance — shreds slightly as it snaps through a correctly tight proximal contact.
  • Floss is continuous from occlusal to gingival — no binding partway down.

Failure modes

  • Floss won't pass — contact too tight. Adjust with a fine diamond strip or a polishing disc, check again, repeat until floss snaps through crisply.
  • Floss passes without resistance — contact open. This isn't fixable chairside; the restoration needs to be remade, or a composite addition at the proximal can sometimes salvage minor open contacts in non-esthetic locations.

Step 5 — Occlusal check

Use articulating paper to mark contacts in centric relation and excursive movements.

What to check

  1. Even contact in CR across all centric holding cusps on opposing teeth.
  2. No high spot on the restoration — marks on the new restoration should be no darker than marks on adjacent teeth.
  3. Group function or canine guidance in excursions, per the patient's existing occlusal scheme. Don't introduce new interferences on lateral or protrusive movements.
  4. No anterior/posterior interference — check that the restoration isn't disarticulating other teeth in excursions.

Adjustment

  • Adjust high spots with a fine diamond or ceramic polishing point at low speed.
  • Always adjust the restoration, not the opposing tooth, unless the opposing tooth is also being evaluated for treatment in the same visit.
  • Polish adjusted occlusal surfaces with a polishing cup and composite polishing paste.

Step 6 — Saliva contamination protocol

If the intaglio contacted saliva during try-in — which it routinely does in pediatric and elderly patients, no matter how careful — the intaglio's primed / abradable surface is now biofilm-contaminated and will not bond reliably.

Always treat the intaglio as contaminated after try-in.

Decontamination

  1. Remove the restoration from the mouth.
  2. Apply Ivoclean (alkaline zirconia oxide suspension, Ivoclar) to the intaglio for 20 seconds. Cover the full intaglio surface.
  3. Rinse thoroughly with water spray.
  4. Air-dry with oil-free compressed air or your operatory air/water syringe.

Do NOT

  • Do not re-etch the intaglio with phosphoric acid as a "cleaning" step. Phosphoric acid removes filler particles from resin surfaces and weakens the bond interface. Ivoclean is specifically formulated not to damage the resin surface while decontaminating.
  • Do not re-abrade unless the contamination is severe (visible blood, long saliva exposure). Re-abrasion resets the bonding sequence — you now need to re-apply primer.
  • Do not skip decontamination even for "brief" try-ins. Saliva proteins bind fast.

Step 7 — Dry and hand off to cementation

After decontamination, air-dry the intaglio thoroughly with oil-free air. Handle by the occlusal from this point forward. The restoration is now ready for the Bonding Protocol.

The 6 mistakes to avoid at try-in

  1. "I'll skip the dry try-in and just load it with cement." You'll set the cement, fail to seat fully, and then try to chip cured cement out of the intaglio. Dry-try always.
  2. "I touched the intaglio with my glove — it's fine." Nitrile glove powder, latex proteins, or hand oils all contaminate the bond. Handle from the occlusal only from step 2 onward.
  3. "I re-etched with phosphoric to clean after saliva contact." H₃PO₄ strips filler from the resin; your bond drops. Use Ivoclean.
  4. "The margin has a small gap — I'll seat it with enough cement." You'll trap cement at the margin and create a chronic perio irritant. Fix the fit or reprint.
  5. "The contact is tight enough — floss doesn't have to snap." Open contacts → food impaction → patient returns in six weeks. Fix before cementation, not after.
  6. "I adjusted the intaglio aggressively to get it to seat." You just invalidated the fit. Reprint.

Disclaimer

This protocol is provided as educational and clinical reference material for licensed dental practitioners. It is based on clinical experience using the OCTOpod workflow with BEGO VarseoSmile TriniQ resin and on standard fixed prosthodontic try-in technique.

Cement manufacturer instructions for use (IFU) supersede any recommendation on this page where the two conflict. Nothing on this page constitutes dental advice, a guarantee of clinical outcome, or a substitute for the practitioner's independent clinical judgment.

OCTOdent does not accept liability for clinical outcomes associated with use of this protocol.

Page last reviewed: 2026-04-19.