These considerations should be seen as one possible source of information and, given the rapid evolving nature of this field, clinicians should also actively review new findings elsewhere as they become available.
Tooth with necrotic pulp and an immature apex
Pulp space not needed for post/core, final restoration
No known allergies to antibiotics if intended for use
Compliant patient (parent/guardian)
Two (or more) appointments
Use of antimicrobial(s)
Possible adverse effects: staining of crown/root, lack of response to treatment, pain/infection
Alternatives: MTA apexification, no treatment, extraction (when deemed non-salvageable)
Permission to enter information into AAE database (optional)
Local anesthesia, rubber dam isolation, access
Copious, gentle irrigation with 20ml 1.5% NaOCl using an irrigation system that minimizes the possibility of extrusion of irrigants into the periapical space (e.g., needle with closed end and side-vents, or EndoVac). The lower concentrations of NaOCl are advised, to minimize cytotoxicity to stem cells in the apical tissues.
Place antibiotic paste or calcium hydroxide. Ca(OH)2 is antimicrobial at concentrations that do not induce stem cell toxicity and is widely available. As an alternative, if the triple antibiotic paste is used: 1) consider sealing pulp chamber with a dentin bonding agent [to minimize risk of staining] and 2) mix 1:1:1 ciprofloxacin:metronidazole:minocycline in a lower concentration (0.01-0.1 mg/ml) to avoid stem cell toxicity; these lower concentrations appear as a liquid form and are no longer a paste.
If triple antibiotic is used, ensure that it remains below CEJ (minimize crown staining). As an alternative, Ca(OH)2 does not cause staining.
Seal with 3-4mm Cavit, followed by IRM, glass ionomer cement or another temporary material
Dismiss patient for 3-4 weeks
Assess response to initial treatment. If there are signs/symptoms of persistent infection, consider additional treatment with the antimicrobial, or an alternative antimicrobial. Recall the patient in about 3-4 weeks as before.
Anesthesia with 3% mepivacaine without vasoconstrictor, rubber dam, isolation
Copious, slow irrigation with 20ml 17% EDTA, followed by normal saline, using a similar closed end needle.
Dry with paper points
Create bleeding into canal system by over-instrumenting (endo file, endo explorer)
Stop bleeding 3mm from CEJ
Place CollaPlug/Collacote at 3mm below CEJ.
Place 3-4mm of a MTA and reinforced glass ionomer and place permanent restoration. Glass ionomer may be an alternative to MTA in cases where discoloration of the crown is a potential concern.
Clinical and Radiographic exam:
No pain or soft tissue swelling (often observed between first and second appointments)
Resolution of apical radiolucency (often observed 6-12 months after treatment)
Increased width of root walls (this is generally observed before apparent increase in root length and often occurs 12-24 months after treatment)
Increased root length
Hargreaves KM, Law AS. Regenerative Endodontics. Chapter 16. Pathways of the Pulp 10th ed. Eds, Hargreaves KM, Cohen S. Mosby Elsevier, St Louis, MO, 2011: 602-19.
Murray PE, Garcia-Godoy F. Stem cells and regeneration of the pulpodentin complex. Chapter 5. Seltzer and Bender’s Dental Pulp – 2nd ed. Eds, Hargreaves KM, Goodis HE, Tay FR.
Quintessence Publishing Co Inc, Hanover Park, IL, 2012:91-108.
Banchs F, Trope M. Revascularization of immature permanent teeth with apical periodontitis: new treatment protocol? J Endod 2004;30:196-200.
Bose R, Nummikoski P, Hargreaves K. A retrospective evaluation of radiographic outcomes in immature teeth with necrotic root canal systems treated with regenerative endodontic procedures. J Endod 2009;35:1343-9.
de Paz S, Pérez A, Gómez M, Trampal A, Domínguez Lázaro A. Severe hypersensitivity reaction to minocycline. J Investig Allergol Clin Immunol. 1999;9(6):403-4
da Silva LAB, Nelson-Filho P, da Silva RAB, Flores DSH, Heilborn C, Johnson JD, Cohenca N. Revascularization and periapical repair after endodontic treatment using apical negative pressure irrigation versus conventional irrigation plus triantibiotic intracanal dressing in dogs' teeth with apical periodontitis. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2010;109:779-87.
Galler KM, D'Souza RN, Federlin M, Cavender AC, Hartgerink JD, Hecker S, Schmalz G. Dentin conditioning codetermines cell fate in regenerative endodontics. J Endod 2011;37(11):1536-41.
Geisler TM. Clinical considerations for regenerative endodontic procedures. Dent Clin North Am 2012;56:603-26.
Hargreaves KM, Geisler T, Henry M, Wang Y. Regeneration Potential of the Young Permanent Tooth: What Does the Future Hold? J Endod 2008;34:S51-S6.
Hargreaves KM, Diogenes A, Teixeira F. Treatment options: biological basis of regenerative endodontic procedures. J Endod In press.
Huang GT-J. Apexification: the beginning of its end. Int Endod J 2009;42:855-66.
Huang GTJ. A paradigm shift in endodontic management of immature teeth: Conservation of stem cells for regeneration. J Dent 2008;36:379-86.
Law A. Considerations for regeneration procedures. J Endod In press.
Lovelace TW, Henry MA, Hargreaves KM, Diogenes A. Evaluation of the delivery of mesenchymal stem cells into the root canal space of necrotic immature teeth after clinical regenerative endodontic procedure. J Endod. 2011 Feb;37(2):133-8.
Martin DE, Henry MA, Almeida JFA, Teixeira FB, Hargreaves KM, Diogenes AR. Effect of sodium hypochlorite on the odontoblastic phenotype differentiation of SCAP in cultured organotype human roots. J Endod 2012 Mar(3):e26
Nosrat A, Seifi A, Asgary S. Regenerative endodontic treatment (revascularization) for necrotic immature permanent molars: a review and report of two cases with a new biomaterial. J Endod. 2011 Apr;37(4):562-7. Review.
Petrino JA, Boda KK, Shambarger S, Bowles WR, McClanahan SB. Challenges in regenerative endodontics: a case series. J Endod. 2010 Mar;36(3):536-41.
Reynolds K, Johnson JD, Cohenca N. Pulp revascularization of necrotic bilateral bicuspids using a modified novel technique to eliminate potential coronal discolouration: a case report. Int Endod J. 2009 Jan;42(1):84-92.
Rodríguez-Lozano FJ, Bueno C, Insausti CL, Meseguer L, Ramírez MC, Blanquer M, Marín N, Martínez S, Moraleda JM. Mesenchymal stem cells derived from dental tissues. Int Endod J. 2011 Sep;44(9):800-6.
Ruparel NB, Teixeira FB, Ferraz CC, Diogenes A. Direct effect of intracanal medicaments on survival of stem cells of the apical papilla. J Endod 2012 Oct(10);38:1372-5.
Thibodeau B, Teixeira F, Yamauchi M, Caplan DJ, Trope M. Pulp revascularization of immature dog teeth with apical periodontitis. J Endod 2007;33:680-9.
Thibodeau B, Trope M. Pulp revascularization of a necrotic infected immature permanent tooth: case report and review of the literature. Pediatr Dent 2007;29:47-50.
Torabinejad M, Turman M. Revitalization of tooth with necrotic pulp and open apex by using platelet-rich plasma: a case report. J Endod. 2011 Feb;37(2):265-8.
Trevino EG, Patwardhan AN, Henry MA, Perry G, Dybdal-Hargreaves N, Hargreaves KM, Diogenes A. Effect of irrigants on the survival of human stem cells of the apical papilla in a platelet-rich plasma scaffold in human root tips. J Endod. 2011 Aug;37(8):1109-15.
Wang XJ, Thibodeau B, Trope M, Lin LM, Huang G. Histologic characterization of regenerated tissues in canal space after the revitalization/revascularization procedure of immature dog teeth with apical periodontitis. J Endod 2010;34:56-63.
Wigler R, Kaufman AY, Lin S, Steinbock N, Hazan-Molina H, Torneck C. Revascularization: A Treatment for Permanent Teeth with Necrotic Pulp and Incomplete Root Development. J Endod In press.
Yamauchi N, Nagaoka H, Yamauchi S, Teixeira FB, Miguez P, Yamauchi M. Immunohistological characterization of newly formed tissues after regenerative procedure in immature dog teeth. J Endod. 2011 Dec;37(12):1636-41.