|Year : 2015 | Volume
| Issue : 3 | Page : 198-202
Regenerative pulp therapy for immature nonvital teeth with plasma-rich fibrin
Amitava Bora, Shabnam Zahir, Gautam Kumar Kundu, Abhirup Goswami
Department of Pedodontics and Preventive Dentistry, Guru Nanak Institute of Dental Science and Research, Kolkata, West Bengal, India
|Date of Web Publication||4-Aug-2015|
108/6 Nagendra Nath Road, Kolkata, West Bengal - 700 028
Regenerative endodontics is a biologically based procedure designed to replace damaged structures such as dentin, root structures, and cells of the pulp dentin complex. Regeneration of dental tissue is possible from a variety of pre existing dental stem cells in a properly disinfected root canal system in the presence of suitable growth factors and scaffold medium. Platelet-rich plasma or platelet-rich fibrin act as ideal three-dimensional scaffold medium and a rich source of growth factors that favors from stem cell multiplication and differentiation. The present case report presents a case of regenerative endodontic procedure in a 11-year-old male child with necrotized 31 and 41 with large periapical radiolucency and extra oral discharging sinus where plasma-rich fibrin has been used as scaffold and a source of growth factors.
Keywords: Regenerative endodontics, plasma-rich fibrin, tri antibiotic paste
|How to cite this article:|
Bora A, Zahir S, Kundu GK, Goswami A. Regenerative pulp therapy for immature nonvital teeth with plasma-rich fibrin. SRM J Res Dent Sci 2015;6:198-202
|How to cite this URL:|
Bora A, Zahir S, Kundu GK, Goswami A. Regenerative pulp therapy for immature nonvital teeth with plasma-rich fibrin. SRM J Res Dent Sci [serial online] 2015 [cited 2019 Dec 5];6:198-202. Available from: http://www.srmjrds.in/text.asp?2015/6/3/198/162184
| Introduction|| |
Modern medical science has moved from surgical model of care to the medicinal model and is likely to move onto the biological model of care, seeking biological replacement of biological tissue. From this perspective, the goal of regenerative dentistry is to induce biological replacement of dental tissues and their supporting structures.  Regenerative endodontics is a biologically based procedure designed to replace damaged structures such as dentin, root structures, and cells of the pulp dentin complex allowing continuous increase in root length and increased thickness of dentinal wall making the toothless vulnerable to fracture.  Permanent teeth with necrotic pulp and immature apex are most suitable for such treatment procedure.  Revascularization through an open apex allows the delivery of mesenchymal stem cells into the root canal space of necrotic immature teeth after a clinical regenerative endodontic procedure.  This could allow host cell homing to form new tissues in the root canal space.  Regenerative endodontics is based on the principles of tissue engineering which require a correct spatial assembly and dynamic interactions between distinct stem cells, growth factors/morphogens, and scaffolds to form a functional pulp dentin complex.  Clinically, regenerative endodontic procedure consists of 1 st phase of disinfection by suitable medicaments followed by 2 nd phase of treatment by blood clot induction or autologous fibrin matrix like platelet-rich plasma (PRP) or platelet-rich fibrin implantation in the canal and periodic follow-ups. 
The present case report presents a case of regenerative endodontic procedure in a 11-years-old male child with necrotized 31 and 41 with large periapical radiolucency and extra oral discharging sinus using plasma-rich fibrin (PRF) as scaffold and utilizing its growth potentials.
| Case Report|| |
An 11-year-old male patient [Figure 1] reported to the outpatient Department of Pedodontics and Preventive Dentistry of Guru Nanak Institute of Dental Science and Research, Kolkata with the chief complaint of recurrent extra oral swelling in lower face and pain in lower front teeth region for last 15 days. There was a history of trauma to the lower front teeth region on biting hard food 7 months back. Dental, medical and familial history was noncontributory. Extra oral examination revealed a large discharging sinus in symphysis area [Figure 2]. Submental lymph node was palpable and tender. Intraoral periapical radiograph of mandibular anterior region [Figure 3] revealed large periapical radiolucency (approx 5 mm in diameter) in relation to 31 and 41. Apical closure was still incomplete in 31 and 41. Intraoral examination revealed first degree yellowish discoloration (according to Jordan and Boskman scale, 1984) of crown structure, and 2 nd mobility (movement of teeth within a range of 1 mm) in 31 and 41. Both the teeth were tender on vertical percussion. Pulp vitality testing by heat test and electric pulp tester (EPT) (Parkel Digitest 2) were performed and both the teeth were found to be nonresponsive.
Considering the age of the patient, pulp vitality status and extent of apical closure, clinical decision of performing regenerative endodontic procedures were taken in 31 and 41. The written informed consent form was signed by the parent of the child.
On the 1 st appointment, access cavity was prepared in 31 and 41 under rubber dam isolation and canals were thoroughly irrigated with 1.5%, 20 ml/canal sodium hypochlorite for 5 min with side vented irrigation needle (Max I Probe) followed by Normal Saline 20 ml/canal for 5 min (according to clinical protocol by American Association of Endodontists (AAE) for a regenerative procedure; 7/31/2013).  The tip of the needle is placed at apical third of the root for achieving proper disinfection of root canal system. No mechanical preparation was done to avoid any harm to varieties of resident stem cells. Canals were dried with paper point and a creamy paste of tri antibiotic paste mixture (minocycline, metronidazole, and ciprofloxacin) in 1:1:1 concentration in normal saline vehicle was placed in the canals with sterile paper points below cemento enamel junction. The access cavity was sealed with a layer of zinc oxide-eugenol cement (Cavit) followed by a second layer of type II glass ionomer cement (Fuji II).
During the second appointment (after 4 weeks), there was no tenderness on percussion, absence of mobility on both vertical and horizontal directions and the extra oral discharging sinus was healed in both 31 and 41 region [Figure 4]. Intraoral periapical radiograph [Figure 5] of 31 and 41 revealed decreased periapical radiolucency. PRF was prepared according to Choukroun's protocol (A 12 ml sample of whole blood was drawn intravenously from the patient's right antecubital vein and centrifuged (R-8C BL, REMI) under 3000 rpm for 10 min to obtain the PRF [Figure 6] which was jelly-like in consistency). Access cavity was reopened and again root canal was thoroughly irrigated with 1.5%, 20 ml/canal sodium hypochlorite for 5 min with side vented irrigation needle (Max I Probe) and saline 20 ml/canal for 5 min. PRF was condensed in the canal with sterile endodontic condenser. White mineral trioxide aggregate (MTA) (Proroot MTA, Densply) of 3-4 mm thickness was placed coronally, and the access cavity was closed with type 2 glass ionomer cement (Fuji II).
|Figure 4: Healed discharging sinus after 4 weeks of application of triantibiotic paste|
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|Figure 5: Intraoral periapical radiograph showing decreased periapical radiolucency after 4 weeks of application of triantibiotic paste|
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The patient was advised for recall visit after 1-month, 3-month, 6-month, 9-month, and 1-year for review. After 1-year follow-up, the teeth showed a negative response to percussion and palpation tests but did not respond positively to heat or an EPT. Radiograph revealed continued thickening of the dentinal walls, root lengthening, regression of the periapical lesion, and apical closure [Figure 7] and [Figure 8]. Patient is advised for regular recall visit in every 6 months.
|Figure 7: Intraoral periapical radiograph after 6-month follow-up showing increased root length, dentinal thickness as well as very little radiolucency present|
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|Figure 8: Intraoral periapical radiograph after 1-year follow-up showing increased root length, dentinal thickness as well as very little radiolucency present|
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| Discussion|| |
Regenerative endodontic procedure is emerging as a very popular alternative to more traditional treatment like apexification in treating nonvital immature permanent teeth as they provide biological replacement of damaged structures such as dentin, root structures and cells of the pulp dentin complex allowing further increase in root length and increase in thickness of dentin making the tooth less vulnerable to fracture. 
Conventional method of regenerative endodontic procedure is to induce blood clot formation by over instrumentation in immature necrotic pulpal space preceded by initial phase of disinfection by tri antibiotic paste combination. However, this procedure might cause discomfort for the patient and most importantly the amount and extent of clot formation cannot be controlled by the operator. The amount of bleeding induction in a long-standing nonvital tooth is also questionable. Hence, there was a quest for a better approach in regenerative endodontics which led to the introduction of autologous fibrin matrix as PRP in the revitalization procedures.  Mahmoud Torabinejad and Turman  documented a case report where role of PRP as scaffold in regenerative procedure is documented.
Plasma-rich fibrin has been shown to have several advantages over traditionally prepared PRP. Its chief advantages include ease of preparation and no need for addition of any activator, which makes this preparation strictly autologous. ,, Recently, studies have demonstrated that the PRF has a very significant slow sustained release of many key growth factors such as PDGF and TGF β for at least 1-week and up to 28 days making it an excellent healing agent. ,, This leads to the idea of using PRF as a capping agent for reparative dentin formation or as a biomaterial for pulp regeneration.  Unlike the PRP, PRF by Choukroun's technique does not dissolve quickly after application; instead the strong fibrin matrix is slowly remodeled in a similar way to a natural blood clot. ,, Another advantage of using PRF as a scaffold is that it has a trimolecular or equilateral fibrin branch junction which makes its architecture flexible and can support cytokine enmeshment and cellular migration, application is also easier for PRF. 
Shivashankar et al. reported a case of revitalization of tooth with necrotic pulp and open apex using PRF. They described evidence of continued thickening of the dentinal walls, root lengthening, regression of the periapical lesion and apical closure with use of PRF. The authors considered PRF to be an excellent biomaterial for pulp dentin complex regeneration. Huang et al. conducted an investigation into the biological effects of PRF on human dental pulp cells. PRF was found to increase dental pulp cell proliferation as well as osteoprotegerin expression in a time-dependent manner. Alkaline phosphatase activity was also significantly up-regulated by PRF. These findings might serve as a basis for preclinical studies that address the role of PRF in reparative dentin formation.
One disadvantage with PRF is placing the material inside the root canal. As PRF is jelly-like and more viscous in consistency, its placement deep inside the canal is very difficult. In the current case PRF was placed in the canal with the help of the endodontic plugger.
Irrigation was done in accordance with clinical considerations by AAE for a regenerative procedure given on 7/31/2013.  No mechanical preparation was done to avoid any harm to varieties of resident stem cells. Disinfection was done with Tri antibiotic paste. Sato et al., investigated this drug combination in vitro and found it to be very effective in the sterilization of carious lesions, necrotic pulps, infected root dentin, and periapical lesions. This drug combination is also effective in killing the bacteria in the deep layers of root canal dentin. 
Finally, over the PRF clot, the MTA was packed and condensed to obtain an excellent bacteria-tight coronal seal.  MTA is used because it gives excellent coronal seal, it is hydrophilic, so moisture contamination does not hamper its setting and also MTA itself provides signaling molecules for growth of stem cells. ,
The AAE clinical considerations for a regenerative procedure given on 7/31/2013  were followed in this case. The initial case selection, placement of medicament, thorough irrigation with minimum mechanical preparation of the canal to avoid injury to pulpal stem cells was done in accordance with clinical considerations by AAE. The AAE clinical considerations for a regenerative procedure advocate formation of scaffold by overinstrumentation of the canal to form a blood clot followed by placement of MTA. It advocates periodic radiographic and clinical follow-up. 
Positive clinical and radiological findings on 1-year postoperative examination confirm the efficacy of PRF as scaffold and a rich source of growth factors in regenerative endodontic Procedure. Negative response to pulp vitality testing may be because of obstruction by coronally present MTA, or complete regeneration of blood vessels and nerve fibers may not have taken place in 1-year period. The nature of resultant tissue is also controversial. Hence, more long-term clinical trials are necessary before establishing regenerative endodontic procedure over conventional methods and moreover comparing PRF or PRP over scaffold formation by blood clot induction with over instrumentation.
| Conclusion|| |
On the basis of current case report, we can conclude that PRF can act as an excellent biomaterial for pulp dentin regeneration under strict asepsis and disinfection of root canal. More clinical trials are necessary to compare the effect of PRP, PRF, and Induced bleeding in the revitalization of tooth with necrotic pulp and open apex on a long term basis.
| Acknowledgment|| |
All the faculties and Postgraduate trainees of Department of Pedodontics and Preventive Dentistry, Guru Nanak Institute of Dental Science and Research, Kolkata.
| References|| |
Hargreaves KM, Law AS. Regenerative endodontics. In: Cohen′s Pathways of the Pulp. 10 th
ed. India: Elsevier; 2011. p. 602-13.
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.
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;37:133-8.
Kim JY, Xin X, Moioli EK, Chung J, Lee CH, Chen M, et al.
Regeneration of dental-pulp-like tissue by chemotaxis-induced cell homing. Tissue Eng Part A 2010;16:3023-31.
Nakashima M, Akamine A. The application of tissue engineering to regeneration of pulp and dentin in endodontics. J Endod 2005;31:711-8.
Geisler TM. Clinical considerations for regenerative endodontic procedures. Dent Clin North Am 2012;56:603-26.
Iwaya SI, Ikawa M, Kubota M. Revascularization of an immature permanent tooth with apical periodontitis and sinus tract. Dent Traumatol 2001;17:185-7.
Torabinejad M, Turman M. Revitalization of tooth with necrotic pulp and open apex by using platelet-rich plasma: A case report. J Endod 2011;37:265-8.
Dohan DM, Choukroun J, Diss A, Dohan SL, Dohan AJ, Mouhyi J, et al.
Platelet-rich fibrin (PRF): A second-generation platelet concentrate. Part I: Technological concepts and evolution. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2006;101:e37-44.
Huang FM, Yang SF, Zhao JH, Chang YC. Platelet-rich fibrin increases proliferation and differentiation of human dental pulp cells. J Endod 2010;36:1628-32.
O′Connell SM. Safety issues associated with platelet-rich fibrin method. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2007;103:587.
Dohan DM, Choukroun J, Diss A, Dohan SL, Dohan AJ, Mouhyi J, et al.
Platelet-rich fibrin (PRF): A second-generation platelet concentrate. Part II: Platelet-related biologic features. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2006;101:e45-50.
Shivashankar VY, Johns DA, Vidyanath S, Kumar MR. Platelet Rich Fibrin in the revitalization of tooth with necrotic pulp and open apex. J Conserv Dent 2012;15:395-8.
Windley W 3 rd
, Teixeira F, Levin L, Sigurdsson A, Trope M. Disinfection of immature teeth with a triple antibiotic paste. J Endod 2005;31:439-43.
Torabinejad M, Rastegar AF, Kettering JD, Pitt Ford TR. Bacterial leakage of mineral trioxide aggregate as a root-end filling material. J Endod 1995;21:109-12.
Torabinejad M, Parirokh M. Mineral trioxide aggregate: A comprehensive literature review - Part II: Leakage and biocompatibility investigations. J Endod 2010;36:190-202.
Gancedo-Caravia L, Garcia-Barbero E. Influence of humidity and setting time on the push-out strength of mineral trioxide aggregate obturations. J Endod 2006;32:894-6.
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