The Critical Apical Diameter to Obtain Regeneration of the Pulp Tissue after Tooth Transplantation, Replantation, or Regenerative Endodontic Treatment.

By Laureys WG, Cuvelier CA, Dermaut LR, De Pauw GA.

Date: 01/2013
Journal: JOE


  • Measure the minimum apical diameter for regeneration to occur.


  • Subjects: single-rooted mature beagle teeth
  • N= 15
  • Experimental Design: extraction -> wire-cutter apicoectomy -> photographed -> replanted for 90 days.
  • Sectioned, stained, and evaluated under light microscope.
  • Criteria of evaluation:the amount of vital tissue filling the pulp chamber 90 days after replantation, 4 different categories were distinguished:
    • 1. More than two thirds of the pulp chamber filled
    • 2. Between one third and two thirds of the pulp chamber filled
    • 3. Less than one third of the pulp chamber filled (apical area only)
    • 4. No ingrowth



  • No teeth showed no ingrowth
  • The new vital tissue in the pulp chamber could be described as well-vascularized cell-rich connective tissue

Clinical Significance:

The minimum diameter of the apical foramen to allow ingrowth is not determined, but a diameter much smaller than 1 mm does not prevent revascularization and ingrowth of new vital tissue (histologically).