Poor finish line design (unclear/irregular margins)
What it is
Creating a finish line (margin) that is not clearly defined, continuous, and smooth — for example: wavy/"chattered" margins, double margins, unsupported enamel lips, uneven width/depth, or a margin that blends into unprepared tooth so the exact line is hard to identify for the scan/impression and for the lab.
Why it happens
• Wrong bur choice / poor control at the cervical third → chatter and irregularities, especially interproximally • Subgingival margin without tissue control (bleeding/crevicular fluid blocks visualization) so the operator "guesses" the margin • Inadequate finish + smoothing: stopping after gross reduction without refining the margin continuity (shows up clinically as low "finish line distinctness") • Digital workflow pitfalls: scanners vary in how well they reproduce finish-line distinctness/accuracy; unclear margins amplify this problem
The full clinical mistake entry includes
- How to avoid it — the prevention protocol
- The clinical tip experienced clinicians use
- The documented reference behind the mistake
More clinical mistakes
Dentalverse is an educational resource for dental students and dentists. This page is a study reference — it is not medical advice and does not replace clinical judgment. Always follow your institution's protocols and your supervisor's guidance.