Why STL Quality Matters

The quality of your intraoral scan directly impacts surgical guide fit and accuracy. A poorly

captured or unprocessed STL file can lead to guide instability, inaccurate implant placement, and

frustrating clinical outcomes.

Common STL Issues

- Holes in mesh: Missing data from scanning artifacts

  • Noise and spikes: From saliva, blood, or scanner errors
  • Incomplete margins: Insufficient gingival capture
  • Excessive file size: Slowing down processing
  • Wrong orientation: Complicating software alignment

Pre-Scan Preparation

Good STL quality starts before scanning:

- Dry the area thoroughly ” moisture causes artifacts

  • Use retraction for better gingival capture
  • Scan systematically to avoid gaps
  • Capture beyond the area of interest for context

> Pro Tip: For edentulous cases, consider a radiographic guide with fiducial markers or use a CBCT with the

patient's denture in place for better soft tissue visualization.

Optimization Steps

1. Import and inspect: Check for obvious errors in mesh viewing software

2. Remove artifacts: Delete floating mesh fragments and spikes

3. Fill holes: Use mesh repair tools for small gaps

4. Smooth surfaces: Light smoothing can improve fit (be careful not to

over-smooth)

5. Reduce file size: Decimate if necessary while preserving critical detail

6. Export properly: Use binary STL format for smaller file sizes

CBCT-STL Registration

The final critical step is proper alignment with CBCT data:

- Identify stable reference teeth or landmarks

  • Use at least 3-4 well-distributed points
  • Verify alignment in all three planes
  • Check cross-sections for consistency

Conclusion

Taking time to properly prepare and optimize your STL files pays dividends in surgical guide

accuracy. If you're consistently having fit issues with guides, the problem often traces back to

scan quality. Don't hesitate to rescan if the initial capture is suboptimal.

STL Files

Intraoral Scanning

Mesh Optimization

CBCT Integration