Common Reasons for Zirconia Crown Remakes (and How to Avoid Them)

Incomplete or Inaccurate Impressions

This is the number one cause of remakes across the industry. If the lab cannot clearly identify the margin, the restoration will not fit. For a deep dive on how to avoid impression-related issues, see our guide on digital vs traditional impressions. Common impression issues include:

• Margin obscured by tissue or blood — inadequate retraction before impression capture
• Voids or pulls in PVS impressions — usually from moisture contamination or premature removal
• Scan stitching errors — digital scan artifacts that distort the preparation geometry
• Missing interproximal data — the scanner or impression material did not capture the area between the prepared tooth and adjacent teeth

Insufficient Occlusal Reduction

Zirconia is strong, but it still needs adequate thickness to function without fracture. Monolithic zirconia requires a minimum of 0.5–1.0 mm of occlusal clearance, while layered restorations need 1.2–1.5 mm to accommodate both the zirconia coping and porcelain overlay.

When reduction is insufficient, the lab has two options: make the restoration too thin (risking fracture) or make it at the correct thickness (resulting in a high restoration that requires significant chairside adjustment). Neither is ideal. Using a reduction guide or putty matrix before preparation helps verify adequate clearance.

Shade Mismatch

Shade remakes are frustrating because the restoration may fit perfectly — it just does not match the adjacent teeth. Common shade-related issues include:

• Shade selected under poor lighting — fluorescent overhead lights distort color perception
• Shade note without a photo reference — the lab has no visual context for how the shade looks in the patient's mouth
• Not specifying value or translucency — two restorations can be the same VITA shade but look different due to opacity or surface texture differences
• Bleaching plans not communicated — if the patient is planning to whiten their teeth, the restoration shade should be selected after bleaching is complete

Poor Communication Between Office and Lab

A surprising number of remakes stem from communication gaps rather than technical errors. The lab cannot read minds. Details that may seem obvious to the clinician are not always clear from the impression or scan alone.

Every case should include clear instructions about the type of restoration (full coverage, implant-supported, etc.), the material preference if you have one, the desired shade with a reference photo, any contacts that need to be particularly tight or open, and whether the patient has specific esthetic concerns.

Fit Issues from Tooth Movement or Tissue Changes

If too much time passes between preparation and impression — or between impression and delivery — the prepared tooth can shift slightly, adjacent teeth can drift, or tissue can heal and change the gingival architecture. This is especially relevant for cases involving temporaries that do not maintain proper contact with adjacent teeth.

Minimize the time between preparation and final impression, and between impression and restoration delivery. A 48-hour lab turnaround significantly reduces this risk compared to a 7–10 day turnaround.

Practical Steps to Minimize Remakes

Based on the cases we process daily, these steps have the biggest impact on reducing remakes:

• Verify your impression or scan before sending — check margin clarity, opposing arch capture, and bite registration
• Use a reduction guide to confirm adequate clearance before finalizing the preparation
• Take a shade photo in natural light with a VITA shade tab held next to the tooth
• Include clear written instructions with every case — even if you have sent similar cases before
• Seat temporaries that maintain contacts and occlusion to prevent drift
• Communicate with your lab when in doubt — a quick call or message can clarify questions before fabrication begins