- Nair et al 1996:
- Few patients had pain; most had extensive caries or coronal breakdown.
- All teeth were extracted with the lesion attached.
- Represented an “unknown fraction” of all extracted teeth with radiolucencies.
- Utilized complete serial sectioning and microscopy (Light and TEM).
- Abbott 1999:
- Biopsies taken during surgery.
- Most teeth had undergone Root Canal Re-treatment before surgery.
- Half had previous apical surgery, especially with retrograde amalgam.
- Many had over-extended previous RCFs or continual pain/infection despite re-treatment.
- Utilized light microscopy on only a few sections.
- Love & Firth 2009, Schultz et al 2009, Wang et al 2004, Becconsall-Ryan et al 2010:
- Biopsies taken during surgery for radiolucencies persisting >4 years or enlarging.
- Some patients had pain.
- RCT was not possible or had already been performed with no healing.
- Utilized light microscopy on up to four sections.