Not protecting adjacent tooth during prep (iatrogenic damage)
What it is
While preparing a proximal box / Class II cavity, the bur (or abrasive strip/disc) nicks, grooves, or removes enamel from the adjacent tooth's proximal surface. This iatrogenic approximal damage is common and clinically important because it increases the future caries risk on that damaged adjacent surface.
Why it happens
• No proximal protection used (no matrix band/guard/separator), so the adjacent tooth is exposed during box breaking and axial wall refinement. • Limited visibility and access in posterior contacts → the bur "jumps" when breaking contact or refining the gingival seat. High reported damage rates in Class II preps reflect this problem. • Conventional approximal box technique can easily damage the adjacent surface; experimental comparisons show conventional prep causes significant adjacent-tooth damage and that protective/alternative systems can reduce it. • Operator technique/training variation (students and practitioners) + time pressure → rushing contact break and undermining enamel.
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
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