Powerpoint presentation on regenerative endodontics

1. GOOD MORNING!
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2. REGENERATIVE ENDODONTICS
Presented by: Dr. Abhisek Bhattacharjee,
JR-2,
Department of Paediatric and Preventive Dentistry,
KGMU, Lucknow.
Date: 22-02-2022
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3. Introduction Routine treatment considered for
necrosed pulp varies from apexification
for non-vital immature teeth and
conventional root canal therapy for
mature non-vital teeth.1
• Drawbacks of conventional endodontic
treatment includes:
• Removal of dentinal tissues
• Less fracture resistance
• Tooth discolouration
• Loss of pulp tissue
1. Gher ME Jr, Dunlap RM, Anderson MH, Kuhl LV. Clinical survey of fractured teeth. J Am Dent Assoc.
1987 Feb;114(2):174-7. doi: 10.14219/jada.archive.1987.0006. Erratum in: J Am Dent Assoc 1987
May;114(5):584. PMID: 3469266.
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4. Apexification • Calcium Hydroxide Apexification:
• Reduction in root strength due to
calcium hydroxide
• Long time span of the entire treatment
• Multiple visits
• MTA Apexification:
• Less appointments
• Does not strengthen the root
• Does not induce further root
development
1. Wu DI, Velamakanni S, Denisson J, Yaman P, Boynton JR, Papagerakis P. Effect of silver diamine fluoride
(SDF)
application on microtensile bonding strength of dentin in primary teeth. Pediatr Dent 2016;38(2):148-53.
2. Mei ML, Zhao IS, Ito L, Lo EC, Chu CH. Prevention of secondary caries by silver diamine fluoride. Int Dent J
2016;66(2):71-7.
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5. Apexogenesis
1961: Nygaard-Ostby: First analysed the
scope of RETs.2
2001: Iwaya et al: Detailed about a
procedure and named it
revascularisation.3
2004: Banchs and Trope: Proposed the
protocol for revascularisation of
immature permanent teeth.4
2. OSTBY BN. The role of the blood clot in endodontic therapy. An experimental histologic study. Acta
Odontol Scand. 1961 Dec;19:324-53. PMID: 14482575.
3. Iwaya SI, Ikawa M, Kubota M. Revascularization of an immature permanent tooth with apical
periodontitis and sinus tract. Dent Traumatol. 2001 Aug;17(4):185-7. doi: 10.1034/j.1600-
9657.2001.017004185.x. PMID: 11585146.
4. Banchs F, Trope M. Revascularization of immature permanent tooth with apical periodontitis: new treatment
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6. 6
A COMPARISON BETWEEN REGENERATIVE
ENDODONTIC TREATMENT AND APEXIFICATION
Lin J, Zeng Q, Wei X, Zhao W, Cui M, Gu J, Lu J, Yang M, Ling J. Regenerative endodontics versus apexification in immature permanent teeth with apical periodontitis: a prospective randomized controlled study. Journal of endodontics.
2017 Nov 1;43(11):1821-7.
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7. 7
DEFINITION OF REGENERATIVE ENDODONTICS
(Murray PE, Garcia-Godoy F, Hargreaves KM. Regenerative endodontics: a review of current status and a call for action. J Endod 2007;33:377-90).
Regenerative Endodontics procedures:
“Biologically based procedures designed to replace damaged structures,
including dentin and root structures, as well as cells of the pulp-dentin
complex’’
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8. 8
Grossmann 13th Edition
Several terms used to describe regenerative endodontic procedure:
1. Regeneration.
2. Revascularization.
3. Revitalization.
The term Revascularization as defined by Andreasen- the
establishment of the vascular supply to existing pulp in immature
permanent teeth.
Revitalization describes the in growth of tissue that may not
resemble the original lost tissue
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9. 9
Regenerative endodontics: a comprehensive review Kim et al. 2018 international endodontic journal
IS THERE DIFFERENCE BETWEEN PULP
REVASCULARIZATION AND PULP
REGENERATION?
Pulp revascularization is the induction of angiogenesis.
Pulp regeneration is pulp revascularization plus the restoration of
functional odontoblasts and/or nerve fibers.
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10. Objectives of
Regenerative
Endodontics
01 Isolation
02 Regeneration of
neuro-
vasculature
03 Apical closure
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11. ROOT CANAL RE-VASCULARIZATION VIA BLOOD
CLOTTING
The blood clot is a source of platelet derived growth factor,
vascular endothelial growth factor, platelet derived epithelial
growth factor and tissue growth factor.
Factors affecting revascularisation
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12. First Appointment
Copious, Gentle
Irrigation
Copious, gentle irrigation
with 20ml NaOCl using an
irrigation system that
minimizes the possibility of
extrusion of irrigants into the
periapical space
Dry Canals with Paper
Points
Dry canals for placement of
intracanal medicament
Place Calcium Hydroxide
Deliver into canal system via
syringe
LA, Dam Isolation and
Access
AAE Clinical Considerations for a Regenerative Procedure Revised 4/1/2018
Local anaesthesia is preferred
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13. 13
Grossmann 13th Edition
If the triple antibiotic paste is used: 1) consider sealing pulp chamber
with a dentin bonding agent
If triple antibiotic is used, ensure that it remains below CEJ
(minimize crown staining).
Seal with 3-4mm of a temporary restorative material.
Dismiss patient for 1-4 weeks
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14. Following guidelines have to be ensured when employing an
antibiotic paste:
• It remains below CEJ (minimize crown staining)
• The pulp chamber is sealed with a dentin bonding agent to
avoid the risk of staining.
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15. 15
Direct Effect of Intracanal Medicaments on Survival of Stem Cells of the Apical Papilla. Nikita BR et al; J Endod 2012; 38 (10): 1372-5
A comparison of SCAP survival when treated with TAP, DAP, mTAP, and
Augmentin at a concentration near LC50 for TAP. Data plotted to compare SCAP
survival among treatment groups at a 1-mg/ml concentration for TAP, DAP,
mTAP, and Augmentin. Data are presented as the mean standard error of the
mean. **P < .01. n.s., not statistically significant as tested by 1-way analysis of
variance.
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16. 16
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17. Second Appointment
AAE Clinical Considerations for a Regenerative Procedure Revised 4/1/2018
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19. 19
EXPECTED OUTCOMES
Diogenes A, Ruparel NB, Shiloah Y, Hargreaves KM. Regenerative endodontics: a way forward. The Journal of the American Dental Association. 2016 May 1;147(5):372-80.
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20. 20
COMPONENTS OF REGENERATIVE ENDODONTICS
SCAFFOLD
GROWTH
FACTORS
STEM
CELLS
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21. 21
STEM CELLS
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22. Isolation of Stem Cells:
(A) Explant method by which dental pulp is fragmented into pieces and cultured in
medium;
(B) Enzymatic digestion method by which dental pulp is digested in collagense/dispase
solution and then the cell suspension obtained is screened for expression of
stemness markers by flow cytometry.
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23. Dental Pulp Stem Cells:
DPSC have the potential to differentiate into either odontoblast-like cells or
fibroblasts.
DPSCs can play an important role in balance of inflammation and repair, dentinogenesis
during invasive caries lesions or pulp exposures.
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Stem Cells from Apical Papilla (SCAP):
Apical papilla is less cellular and vascular compared to
dental pulp but SCAP compared to DPSCs shows a
proliferation rate higher by 2-3 folds.
Sonoyama W, Liu Y, Yamaza T, et al. Characterization of the apical papilla and its residing stem cells from human immature permanent teeth: a pilot study. J Endod. 2008;34(2):166-171.
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26. Be Na Lee et al (2015) A review of the regenerative endodontic treatment Procedure. restorative dentistry and endodontics 2015.
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27. Isolation
(A)Periapical radiographs of the apical
papillae related to the apex of a human
premolar;
(B)(B–D) Extracted premolars with intact
apical papillae.
(C)(E) Apical papilla separated gently
using tweezers;
(D)(F) Scalpel dissection of apical papilla
tissue in a cell culture dish with culture
medium.
(E)(G,H) Cultured human SCAP at 4x
after primary culture at 8 and 21 days,
respectively.
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30. GROWTH FACTORS
Growth factors are proteins that bind to receptors on the
cell and induce cellular proliferation and/or differentiation.
Growth factor
Stem cell
Desirable structure
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31. Common Growth Factors
Murray PE, Garcia-Godoy F, Hargreaves KM. Regenerative endodontics: a review of current status and a call for action. Journal of endodontics. 2007 Apr 1;33(4):377-90. 31 of 58

32. Transforming growth factor beta (TGF) family, are important in cellular
signaling for odontoblast differentiation and stimulation of dentin matrix
secretion. (Roberts-Clark DJ, Smith AJ. Angiogenic growth factors in human dentine matrix. Arch Oral Biol 2000;45:1013– 6.)
Recombinant human BMP2 stimulates differentiation of adult
pulp stem cells into an odontoblastoid morphology in culture.
(Nakashima M, Nagasawa H, Yamada Y, Reddi AH. Regulatory role of transforming growth factor-beta, bone morphogenetic protein-2, and protein-4 on gene expression of
extracellular matrix proteins and differentiation of dental pulp cells. Dev Biol 1994;162:18 –28.)
•Recombinant BMP-2, -4, and -7 induce formation of reparative
dentin in vivo.
•(Nakashima M. Induction of dentin formation on canine amputated pulp by recombinant human bone morphogenetic proteins (BMP)-2 and -4. J Dent Res 1994; 73:1515–22.)
The application of recombinant human insulin-like growth
factor-1 together with collagen has been found to induce
complete dentin bridging and tubular dentin formation. (Lovschall H, Fejerskov
O, Flyvbjerg A. Pulp-capping with recombinant human insulin- like growth factor I (rhIGF-I) in rat molars. Adv Dent Res 2001;15:108 –12.)
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This indicates the potential of adding
growth factors before pulp capping,
or incorporating them into restorative
and endodontic materials to stimulate
dentin and pulp regeneration. In the
longer term, growth factors will likely
be used in conjunction with postnatal
stem cells to accomplish the tissue
engineering replacement of diseased
tooth pulp.
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37. 37
SCAFFOLDS
It is a 3- dimensional matrix of a specific geometric configuration on which
seeded cells grow to produce the desired tissue or organ.
1. Leads to improved and faster tissue development.
2. Contains nutrients to promote cell survival and
growth.
3. May contain antibiotics to prevent bacterial in
growth in the canal systems.
Inuyama Y, Kitamura C, Nishihara T, et al. Effects of hyaluronic acid sponge as a
scaffold on odontoblastic cell line and amputated dental pulp. J Biomed Mater Res B
Appl Biomater 2010;92(1):120–8
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Scaffolds
Natural
(a) proteins like collagen,
fibrin and silk (b)
polysaccharides like
chitosan, hyaluronic acid,
alginate and agarose.
Synthetic
poly lactic acid (PLA), poly
glycolic acid (PGA), poly
lactide-co- glycolic acid
(PLGA) and polycaprolactone
(PCL).
Rigid
Non-rigid
Natural biomaterials offer good cellular
compatibility. Their disadvantages include
source variability, immunogenicity, if not
pure, limited range of mechanical
properties and lack of control over pore
size.
synthetic biomaterials can be
manufactured in unlimited supply under
controlled conditions, are cheaper and can
be tailored to obtain desired shape, cell
differentiation properties and mechanical
and chemical properties especially the
strength, pore characteristics and
degradation rate suited for intended
applications. However, synthetic
biomaterials lack cell adhesion sites and
require chemical modifications to improve
cell adhesion.
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39. Platelet Rich Plasma:
PRP - rich in platelet-derived growth factor (PDGF),
transforming growth factor-beta (TGF-β), and insulin-like
growth factor 1 (IGF-1) to the surgical site.
Promote wound healing and stimulate bone regeneration.
Bezgin T, Yılmaz AD, Celik BN, Sönmez H. Concentrated platelet‐rich plasma used in root canal revascularization: 2 case reports. International endodontic journal. 2014 Jan;47(1):41-9.
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41. Clinical Notes:
• No EDTA because it could damage the platelet membrane.
• Therefore, anticoagulants with citrate and dextrose of sodium
citrate are recommended.
• PRP activation prior to injection by combining the cPRP with
equal volumes of sterile saline solution containing 10%
calcium chloride and sterile bovine thrombin (100 U/mL) in a
sterile well plate.
• Mixture is then injected into the canal space up to the level of
the CEJ and allowed to clot for 10 min
Bezgin T, Yılmaz AD, Celik BN, Sönmez H. Concentrated platelet‐rich plasma used in root canal revascularization: 2 case reports. International endodontic journal. 2014 Jan;47(1):41-9.
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43. Platelet Rich FIbrin:
Is one of the most commonly used scaffolds in regenerative
endodontic procedures.
The fibrin matrix contains a large quantity of platelet and
cytokines.
Fibrin helps in migration of fibroblasts and endothelial cells
and is the source of growth factors that aid in
revascularization.
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Preparation of PRF:
30 MINUTES
BEFORE THE
CLINICAL
PROCEDURE
8.5 ML
BLOOD -
VENIPUNCTU
RE
BLOOD COLLECTED
IN 10ML STERILE
GLASS TUBE
WITHOUT
ANTICOAGULANT
IMMEDIATELY
CENTRIFUGED AT
3000 RPM FOR 10
MINUTES.
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Types of PRF:
Aizawa H, Tsujino T, Watanabe T, Isobe K, Kitamura Y, Sato A, Yamaguchi S, Okudera H, Okuda K, Kawase T. Quantitative near-infrared imaging of platelets in platelet-rich fibrin (PRF) matrices:
comparative analysis of bio-PRF, leukocyte-rich PRF, advanced-PRF and concentrated growth factors. International Journal of Molecular Sciences. 2020 Jan;21(12):4426.
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47. PRF vs PRP:
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48. Advantages of PRF over PRP:
A comparative evaluation of the blood clot, platelet-rich plasma, and platelet-rich fibrin in regeneration of necrotic immature permanent teeth: A clinical study Isha Narang et al,contempory clin dent2015 Jan-Mar; 6(1): 63–68
Higher concentration of cytokines in PRF over PRP.
Slow physiological polymerization in PRF that supports cytokine
growth and cellular migration.
PRF releases its growth factors steadily with the peak level
reaching at 14 days which in corresponding to the growth pattern
of periapical tissues
PRP has poor mechanical properties because its liquid or gel
form results in washing out of released growth factors such as
during an operation.
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Why Platelet Rich Scaffolds are better than blood clots?
Clinically, it is difficult to control the speed and volume of
bleeding.
It has been documented that iatrogenic mental nerve paresthesia can be
caused by an overfill of Gutta-Percha or by mechanical instrumentation
beyond the root apex .
Lv H, Chen Y, Caet al ;The efficacy of platelet-rich fibrin as a scaffold in regenerative endodontic treatment: a retrospective controlled cohort study. BMC oral health. 2018 Dec;18(1):1-8.
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50. Potential technologies for regenerative endodontics:
A. Postnatal stem cell therapy
B. Pulp implantation
C. Scaffold implantation
D. Injectable scaffold delivery
E. Three-dimensional cell printing
F. Gene delivery.
Peter E. Murray. Et al Regenerative Endodontics: A Review of Current Status and a Call for Action.JOE — Volume 33, Number 4, April 2007
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51. Injectable Scaffold Delivery:
Hydrogels are injectable scaffolds that can be delivered by
syringe in root canal.
Peter E. Murray. Et al Regenerative Endodontics: A Review of Current Status and a Call for Action.JOE — Volume 33, Number 4, April 2007
ADVANTAGES
Noninvasive.
Easy to deliver into root canal system.
DISADVANTAGES
Limited control over tissue formation
Low cell survival rate
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52. Three-Dimensional Cell Printing:
The ideal positioning of cells in a tissue engineering construct
would include placing odontoblastoid cells around the
periphery to maintain and repair dentin, with fibroblasts in the
pulp core supporting a network of vascular and nerve cells.
Peter E. Murray. Et al Regenerative Endodontics: A Review of Current Status and a Call for Action.JOE — Volume 33, Number 4, April 2007
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53. Gene Therapy:
• Based introduction of genes into target cells with the aim of altering their
phenotype or protein expression profile.
• Limited research work done.
• Gene delivery in endodontics would be used to deliver mineralizing genes
into pulp tissue to promote tissue mineralization.
Peter E. Murray. Et al Regenerative Endodontics: A Review of Current Status and a Call for Action.JOE — Volume 33, Number 4, April 2007
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54. Future of stem cell research:
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Take Home Message:
“IF THERE WERE NO REGENERATIONS, THERE COULD BE
NO LIFE.
IF EVERYTHING REGENERATED, THERE WOULD BE NO
DEATH”
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57. QUESTIONS
1) According to present available research, the ideal concentrations of irrigants for revascularization is:
A. 3% NaOCl and 15% EDTA
B. 1.5% NaOCl and 17% EDTA
C. 1.2% Chlorhexidine and 1.5% EDTA
D. 3% NaOCl and .2% Chlorhexidine.
2) 13 y/o male child reports with history of trauma 3 years back. Radiograph reveals open apex. Ideal
treatment plan for this patient will be:
A. RCT followed post and core build-up and crown
B. Apexification followed by obturation with gutta percha and then post
and core+crown
C. Revascularisation followed by RCT on completion of apical closure and then
Post and core+rown.
D. Extraction followed by implant supported prosthesis
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58. QUESTIONS
3) Which of the following is not a component of regenerative endodontic treatment?
A. Stem cells
B. Scaffold
C. Growth factors
D. Obturating material
4) 15 y/o male child reports with history of trauma 2 years back. Ideal endodontic treatment plan for
tooth #21 will be:
A. RCT
B. Apexification
C. Direct pulp capping
D. Revascularisation
5) Which of the following is a must for successful regenerative endodontic treatment?
A. Blood clot
B. PRF scaffold
C. Biomechanical preparation
D. Isolation
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