efficacy of platelet-rich plasma as a scaffold in...

Clinical Research

Efficacy of Platelet-rich Plasma as a Scaffold in RegenerativeEndodontic TreatmentTugba Bezgin, DDS, PhD,* Ayca Dilara Yilmaz, PhD,† Burcu Nihan Celik, DDS,*Mehmet Eray Kolsuz, DDS, PhD,‡ and Hayriye Sonmez, DDS, PhD*

Abstract

Introduction: Current research is concerned with discov-ering better scaffolds for use in regenerative endodontictreatment. This study aimed to clinically and radiograph-ically evaluate the efficacy of platelet-rich plasma (PRP)used as a scaffold in regenerative endodontic treatmentand compare it with that of a conventional blood clot(BC) scaffold. Methods: A total of 20 necrotic, single-rooted immature teeth were randomly distributed into 2groups. After disinfecting the root canal space with tripleantibiotic paste (1:1:1 ciprofloxacin, metronidazole, andcefaclor), a tissue scaffold was created by using eitherPRP or BC and covered with white mineral trioxide aggre-gate. Clinical and radiographic follow-up examinationswere performed once every 3 months during an 18-month period. Differences in root area were calculatedfrom preoperative and postoperative radiographs. Fisherexact and Mann-Whitney U tests were used to evaluatedifferences between groups, with P value .05). Conclusions: PRP successfully created a scaffoldfor regenerative endodontic treatment; however, treat-ment outcomes did not differ significantly between PRPand conventional BC scaffold. (J Endod 2015;41:36–44)

Key WordsBlood clot, immature teeth, platelet-rich plasma, regen-erative endodontic treatment

From the *Department of Pedodontics, Faculty of Dentistry,Ankara University, Ankara, Turkey; †Molecular Biology Labora-tory, Faculty of Dentistry, Ankara University, Ankara, Turkey;and ‡Department of Maxillofacial Radiology, Faculty ofDentistry, Ankara University, Ankara, Turkey.

Address requests for reprints to Dr Tu�gba Bezgin, Ankara€Universitesi, Diş Hekimli�gi Fak€ultesi, Pedodonti Ana BilimDalı, Beşevler, Ankara 06500, Turkey. E-mail address:[email protected]/$ - see front matter

Copyright ª 2015 American Association of Endodontists.http://dx.doi.org/10.1016/j.joen.2014.10.004

36 Bezgin et al.

Necrotic, immature permanent teeth may benefit from biologically based treat-ment approaches in terms of restoring root development and reinforcingdentinal walls to increase the likelihood of long-term tooth retention (1–4). Aretrospective study has shown a higher survival rate with regenerative endodontictreatment (RET) when compared with both mineral trioxide aggregate (MTA) andCa(OH)2 apexification (5).

With regenerative procedures, the growth and development of cells and vascu-lature are achieved by providing a framework scaffold that can also be infused witha variety of factors (1, 6). The suggested protocol for scaffold creation entails theintentional induction of bleeding from the periapex and the formation ofan intracanal blood clot (BC) (7). Several reports have been published demon-strating good success with BC scaffolds (8–13); however, because it is notalways possible to invoke bleeding in the root canal (14, 15), researchers havebegun examining other three-dimensional scaffolds that can be constructed withor without bleeding (2).

Recent studies have reported on scaffold creation by using platelet-richplasma (PRP) (16–20), a volume of autologous plasma containing elevatedplatelet concentrations and thus greater amounts of growth factors to assist instem cell proliferation for healing induction and tissue regeneration (21, 22).Growth factors released from PRP play an important role in regulating cellularprocesses such as mitogenesis, chemotaxis, differentiation, and metabolism forstimulation of healing (22). PRP is being widely used in various surgical fields,including head and neck surgery, otolaryngology, cardiovascular surgery, andoral and maxillofacial surgery (21). In RET, although some researchers haveused PRP as an adjunct to BC scaffolds (17, 19, 20), both Torabinejad andTurman (16) and Bezgin et al (18) have reported on cases in which PRP aloneresulted in successful scaffold formation, suggesting the need for prospectivestudies to confirm the capacity of PRP alone to provide successful revasculariza-tion. Therefore, the present study aimed to clinically and radiographically evaluateand compare the use of PRP and BC as scaffolds in RET of necrotic immatureteeth. The null hypothesis tested in this study was that treatment success wouldbe better with PRP than with a BC scaffold.

Materials and MethodsA total of 22 teeth in 20 children (8 girls, 12 boys) aged 7–13 years (mean age,

9.95 years) were initially selected from among patients attending the pediatric dentistryclinic. Each child had at least 1 necrotic, immature, single-rooted tooth requiring rootcanal treatment. None of the teeth had been previously treated for necrosis. All childrenwere healthy and cooperative. After receiving ethical approval from the Institutional Re-view Board, the risks and possible outcomes of RET, as well as subsequent treatment incase of failure, were explained to parents, who gave their informed consent for theirchildren’s participation in the study.

Inclusion criteria for teeth were as follows:

1. Pulp necrosis, with or without periapical lesions2. Possibility of restoration3. No root fracture, ankylosis, pathologic mobility, or probing depths >3 mm (2, 7)

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Figure 1. (A) Concentrated PRP application to the root canal. (B) Photograph showing MTA placement.

Clinical Research

Pulp necrosis was tentatively diagnosed by dental history and clin-ical examination, which included electric pulp testing (Digitest, Parkell,NY) and cold stimulation testing (Chloraethyl, Wehr Baden, Germany).Clinical signs and symptoms such as pain, swelling, fistula, and sensi-tivity to percussion and palpation were also noted. Teeth with periapicallesions were grouped according to the size of the lesion as follows:

Size 1: Lesion in the apical region onlySize 2: Lesion involving one third to one half of the rootSize 3: Lesion involving more than one half of the root

Treatment ProceduresTeeth were randomly distributed between the 2 treatment groups

by assigning each tooth a number and then assigning all odd-numberedteeth to the PRP group (n = 11) and all even-numbered teeth to the BCgroup (n = 11). All treatment was performed by the same pediatricdentist.

RET was performed according to the American Association of End-odontists’ protocol described below. Local anesthesia was administered(2% lidocaine with 1:100,000 adrenaline), teeth were isolated with arubber dam, the pulp chamber was accessed, and the working lengthwas determined by using a size 20 sterile K-file. The diagnosis of totalpulp necrosis was confirmed while determining the working length,with 1 tooth assigned to the PRP group that showed sensitivity in the api-cal third of the root canal rediagnosed as having partial necrosis andexcluded from the study. Canals were not instrumented but were irri-gated copiously with 2.5% NaOCl (20 mL), sterile saline (20 mL),and 0.12% chlorhexidine (10 mL) and dried with sterile paper points.After sealing the pulp chamber with a dentin bonding agent to minimize

TABLE 1. Interexaminer and Intraexaminer Kappa Values for PreoperativeLesion Size, Bony Healing, and Apical Closure

Kappa P value

Preoperative lesion size (Dentist 1-Dentist 1) 1 .0001Preoperative lesion size (Dentist 1-Dentist 2) 0.793 .0001Preoperative lesion size (Dentist 2-Dentist 2) 0.897 .0001Bony healing (Dentist 1-Dentist 1) 1 .0001Bony healing (Dentist 1-Dentist 2) 1 .0001Bony healing (Dentist 2-Dentist 2) 1 .0001Complete apical closure (Dentist 1-Dentist 1) 1 .0001Complete apical closure (Dentist 1-Dentist 2) 0.894 .0001Complete apical closure (Dentist 2-Dentist 2) 1 .0001

Figure 2. (A) Outlining of total root area in preoperative radiograph. (B)Outlining of canal space in preoperative radiograph. (C) Outlining of totalroot area in 18-month follow-up radiograph. (D) Outlining of canal spacein 18-month follow-up radiograph.

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TABLE 2. Intraobserver Analysis for Radiographic Root Area Measurements

n Mean Median Minimum Maximum SD

Wilcoxon signed rank test

z P value

Preoperative 1 19 18.36 18.59 12.64 25.61 3.27 –0.610 .542Preoperative 2 19 18.28 18.07 12.23 25.59 3.22Postoperative 1 19 20.27 20.34 13.54 29.48 3.72 –0.684 .494Postoperative 2 19 20.34 20.71 13.01 28.09 3.57

SD, standard deviation.

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the risk of staining, equal proportions of metronidazole (Flagyl;Eczacıbaşı Inc Co, Istanbul, Turkey), ciprofloxacin (Cipro; BiofarmaInc Co, Istanbul, Turkey), and cefaclor (Sanocef; Sanovel Inc Co,Istanbul, Turkey) were ground to a powder and mixed with distilled wa-ter into a creamy paste that was placed in the canal below the cemen-toenamel junction (CEJ) by using a lentulo spiral in a slow-speedhandpiece. Canals were sealed with cotton pellets and reinforcedwith zinc oxide–eugenol cement (IRM; Dentsply, Milford, DE). Patientswere recalled after 3 weeks, and in cases of persistent signs of infection(ie, purulent drainage, failure to resolve pain, swelling, fistula, andsensitivity to percussion and palpation), triple antibiotic dressing wasapplied again.

In the following visit, teeth were re-accessed under a rubberdam, the antibiotic paste was removed by rinsing with a solutionof 5% EDTA (20 mL) and sterile saline (20 mL), canals were driedwith sterile paper points, and scaffolds were created according tothe assigned group. Because PRP application involves no dentalpain, no anesthetic was applied in the PRP group. PRP was pre-pared according to Dohan et al (23). Coagulation was achievedby combining PRP with equal volumes of sterile saline solution con-taining 10% calcium chloride and sterile bovine thrombin (100 U/mL). The PRP mixture was injected into the canal space up to thelevel of the CEJ and allowed to clot for 10 minutes (Fig. 1A). Finalrestoration was completed with white MTA (Angelus, Londrina,Brazil) prepared according to the manufacturer’s instructions(Fig. 1B), reinforced glass ionomer cement (Ketac Molar Easymix;3M ESPE, Seefeld, Germany), and composite resin (Filtek SupremeXT; 3M ESPE, St Paul, MN) during the same visit.

In the BC group, an adrenaline-free local anesthetic solution(Citanest; AstraZeneca, London, UK) was applied, and a size #20K-file was used to evoke bleeding in the root canal. Once bleedingreached the level of the CEJ, the tooth was allowed 10 minutes toform a blood clot, and the final restoration was completed as

Figure 3. (A) Radiograph of teeth #8 and #9 showing size 1 lesion. (B) Radiographlesion.

38 Bezgin et al.

described above for the PRP group. Bleeding could not be achievedin the root canal of 1 tooth, which was subsequently excluded fromthe study.

Clinical and Radiographic ExaminationsClinical and radiographic follow-up examinations were performed

once every 3 months during an 18-month follow-up period by 2 expe-rienced pediatric dentists blinded to the scaffold used in treatment.

Treated teeth were examined for vitality by using both electric pulpand cold testing, and teeth were recorded as responding positively tovitality testing only if they responded positively to both tests. At theend of 18months, periapical radiographs were independently evaluatedby 2 pediatric dentists for periapical healing and apical closure. Radio-graphs were reexamined 1 month after the initial examinations by thesame pediatric dentists, and intraexaminer and interexaminer validitywas assessed by using kappa statistics. Kappa values ranged from 0.8to 1, demonstrating good reliability (Table 1).

In addition, preoperative and 18-month recall radiographs ofteeth judged successful were digitally scanned, and radiographic rootarea (RRA) measurements were performed by using the Image J soft-ware (version 1.44) by a radiologist with experience using the programand who was blinded to the study groups. The ImageJ TurboReg plug-inwas used to align and normalize preoperative and postoperative films.RRA was calculated from all radiographs according to Flake et al (24)(Fig. 2). Measurements were repeated after 3 weeks, and increases be-tween preoperative and postoperative RRAs were calculated by using theaverages of the 2 measurements. Wilcoxon signed rank test showedgood intraexaminer reliability (Table 2).

After these examination periods, the 2 pediatric dentists jointlyevaluated all clinical and radiographic findings with addition of RRAmeasurements and scored the final success rates for all patients, as fol-lows:

of tooth #8 showing size 2 lesion. (C) Radiograph of tooth #20 showing size 3


TABLE 3. Treatment Outcomes after 18-month Follow-up

Tooth

Patientage (y)and sex

Toothtype Etiology

Preoperativeacute

symptomsPreoperativelesion size

Months tocompletehealing ofperiapicallesion

Completeapicalclosure

Increase inRRA (%)

Positiveresponse to

vitalitytesting

Successscore

PRP1 11/M Premolar Caries Yes — — Yes 7.1 Yes 32 9/M Incisor Trauma No — — Yes 12.5 Yes 33 12/M Premolar Caries No — — Yes 23.3 No 24 11/M Premolar Caries Yes 3 3 Yes 15.1 No 25 8/F Incisor Trauma Yes 2 6 Yes 2.7 Yes 36 12/F Premolar Caries Yes 1 3 Yes 10 Yes 37 10/M Incisor Trauma Yes 3 9 No –0.4 No 18 12/M Incisor Trauma Yes 3 9 No 5.1 No 19 7/M Incisor Trauma Yes 1 3 Yes 19.8 Yes 310 8/F Incisor Trauma Yes 1 12 No 3.4 No 1

BC1 11/F Premolar Caries Yes 1 3 Yes 10 No 22 9/M Incisor Trauma Yes 2 9 Yes 20 No 23 8/F Incisor Trauma No — — Yes 36.5 Yes 34 12/M Incisor Trauma Yes 1 6 Yes 2.5 No 25 12/F Incisor Trauma Yes 2 9 No 5.6 No 16 12/F Incisor Trauma Yes 2 9 No 5.8 No 17 8/F Incisor Trauma No 3 12 No 6.8 No 18 12/F Premolar Caries Yes 2 3 Yes 24 Yes 39 7/M Incisor Trauma Yes 1 — No — No 010 8/M Incisor Trauma Yes 1 3 Yes 2.2 No 2

BC, blood clot; F, female; M, male; PRP, platelet-rich plasma.

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Score 0 (unsuccessful): Teeth with clinical signs/symptoms (pain,tenderness to percussion, swelling, fistulization, or pathologicmobility) and/or radiographic pathology (evidence of periradicularpathosis, increase in periapical radiolucency, or internal/externalroot resorption)Score 1 (satisfactory): Elimination of symptoms and evidence ofbony healing but no increase in RRA or no apical closureScore 2 (good): Elimination of clinical symptoms and evidence ofbony healing, with apical closure achieved with/without increase inroot areaScore 3 (excellent): Score 2 + positive response to vitality testing

Statistical AnalysisStatistical analysis was performed by using the software program

SPSS 20.0 (SPSS 20.0 for Windows; SPSS Inc, Chicago, IL). Clinicaland radiographic data were assessed by using Fisher exact test, anddifferences in RRA between the 2 groups were assessed by using theMann-Whitney U test, with P value .05), although size 1 lesions required a mean time of 4.2months for complete healing, compared with 8.3 months for both size2 and size 3 lesions. Differences in healing time between the PRP andBC groups were also statistically insignificant, although complete heal-ing occurred sooner in the PRP group (mean, 6.4 months) than in theBC group (mean, 6.8 months). Differences in time required for com-plete apical closure were also similar between the groups, althoughthe PRP group required a mean of 8.1 months for complete apicalclosure, compared with 9 months in the BC group. However, thetime required for complete apical closure was significantly longer inpatients with acute preoperative symptoms such as night pain, spon-taneous pain, and extreme sensitivity to percussion (10.2 months)when compared with patients without signs and symptoms (6 months)(P < .05).

In terms of RRA, teeth in the BC group exhibited amean increase of12.6% in RRA, compared with 9.86% in the PRP group; however, thedifference between groups was statistically insignificant (P > .05)(Table 3).

PRP in Regenerative Endodontics 39

Figure 4. (A) Preoperative radiograph of teeth #8 and #9 showing radiolucent lesions and open apices. (B) Immediate post-treatment radiographs of tooth #8(BC group) and tooth #9 (PRP group). (C) Three-month follow-up radiograph. (D) Six-month follow-up radiograph. (E) Nine-month follow-up radiographshowing increase in periapical lesion in tooth #8. (F) A barrier was observed 2 mm coronally from the apex that restricted MTA placement in tooth #8.(G–I) Twelve- to 18-month follow-up radiographs.

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No discoloration in relation to the triple antibiotic paste containingcefaclor was observed; however, crown discoloration caused by MTAplacement was common, with unaesthetic results in 12 of 20 cases(60%).

Partial pulp canal obliteration was observed in 8 cases (PRP, 4;BC, 4) (Fig. 5); however, no relationship was found between oblitera-tion and any of the variables (lesion presence/size, necrosis etiology,preoperative symptoms, treatment group) (P > .05).

A total of 7 teeth responded positively to vitality testing (PRP, 5;BC, 2), with no statistically significant difference between the groups(P > .05).

Treatment OutcomesTreatment outcome was evaluated after an 18-month follow-up

period on the basis of subjective and objective clinical findings and radio-

40 Bezgin et al.

graphic evidence. Scores for both groups ranged from ‘‘satisfactory’’ to‘‘excellent’’ (Table 3) (Figs. 6–8), and although the PRP group had ahigher rate of ‘‘excellent’’ scores, indicating better outcomes, thedifference between groups was statistically insignificant (P > .05).

DiscussionThis study found a PRP scaffold to be effective when used in RET of

necrotic immature teeth; however, treatment outcomes did not varysignificantly between PRP and conventional BC scaffold. Therefore,the null hypothesis was rejected.

Geisler (2) has stated that regenerative therapy outcomes mayvary between teeth exhibiting partial necrosis (ie, teeth with some vi-tal tissue in the apical portion of the canal) and those exhibiting fullnecrosis (ie, teeth in which the pulp has been completely lost).Huang (3) has suggested that the type of pulpal regeneration varies


Figure 5. (A) Preoperative radiograph of tooth #13 showing deep carious lesion and incompletely developed apex. (B) Twelve-month follow-up radiograph. (C)Partial pulp canal obliteration observed at 18-month follow-up.

Clinical Research

according to these different clinical situations. In the case of partialpulp necrosis, the remaining pulp tissue may hypothetically recoverafter disinfection and help to regenerate the lost portion of pulp;therefore, the prognosis of these teeth is good. By contrast, in thecase of complete loss of pulp tissue requiring de novo synthesisof pulp, prognosis is poor, and a separate protocol and scaffoldmay be required (2, 3). This study evaluated the efficacy of PRPused alone as a scaffold in cases of de novo regeneration; at theend of 18 months, all teeth in the PRP group showed resolutionof signs and symptoms, and 90% of teeth in the PRP groupshowed various degrees of root maturogenesis.

Figure 6. (A) Preoperative radiograph of tooth #9. (B) Immediate post-treatme(H) At 18-month follow-up, bony healing was evident without root maturogenesis.


The RRA measurements used in this study are considered to pro-vide a valid assessment of the amount of root maturogenesis obtained asan outcome of RET (24). Flake et al (24) consider a mean RRA increaseof 31% to represent obvious root development. In this study, an overallmean increase of 11%was detected. The amount of increase in RRAmaybe related to the preoperative root maturation stage of treated teeth, withsmall increases in RRA occurring in successfully treated teeth that wererelatively more developed before treatment. Because RRA provides noinformation about periapical status, in addition to RRA, the presentstudy relied on visual assessment of bony healing and apical closurein evaluating treatment outcomes.

nt periapical radiograph. (C–G) Three- to 15-month follow-up radiographs.


Figure 7. (A) Preoperative radiograph of tooth #29 showing radiolucentlesion and open apex. (B) Immediate post-treatment radiograph. (C–G)Three- to 15-month follow-up radiographs. (H) At 18 months, apical closureand complete healing of periapical lesion can be appreciated. Clinically, toothgave negative response to vitality tests.

Figure 8. (A) Preoperative radiograph of tooth #20. (B) Immediate post-treatment radiograph. (C–G) Three- to 15-month follow-up radiographs.(H) At 18-month follow-up, apical closure by narrowing of apical foramenand convergence of apical walls was observed with positive response to vitalitytests.

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After an 18-month follow-up period, no statistically significant dif-ferences in outcomes were observed between the PRP and BC groups inthe present study, although more ‘‘excellent’’ scores were obtained inthe PRP group. Previous studies by Jadhav et al (17, 19) found PRPto be more effective than BC; however, because these studies usedPRP as an addendum to a BC matrix and with collagen as a carrier,the results cannot be attributed to PRP alone but may be due tosynergy among the materials. The present study’s finding that PRPalone did not significantly affect treatment outcomes is in line withrecent histologic reports (20, 25, 26). Zhu et al (26) used PRP anddental pulp cells for pulp regeneration in a dog studymodel. They foundthat the rate of root canal wall thickening was lower and mineralizedtissue formation was less when PRP was used alone. This result wasattributed to faster degradation of growth factors in PRP, which causedthem to have shorter activity. In addition, growth factors were shown tohave varying effects that may enhance or inhibit osseous and soft tissuerepair, depending on the dynamics of the wound environment (21, 27).Martin et al (20) concluded that PRP may enhance wound healing onlyif parenchymal tissue has not been completely destroyed but may nototherwise induce tissue regeneration. This would explain the similar

42 Bezgin et al.

outcomes between PRP and BC in the present study, because only totallynecrotic teeth were included.

In the present study, 6 teeth (PRP, 3; BC, 3) showing bony healingbut no further root development were rated ‘‘satisfactory,’’ the lowestpossible rating for a successful outcome. Nosrat et al (28) also reporteda case in which no further root maturation occurred in 6 years, despitethe resolution of periapical pathology, and Kahler (29) reported rootmaturogenesis in 2 patients after 36 months and recommended longerperiods of review. Geisler (2) suggested that even if no further rootmaturation has occurred, teeth showing resolution of periapical pathol-ogy do not necessarily require further endodontic treatment if they areasymptomatic. In the present study, teeth exhibiting bony healing but noroot maturation were considered successful because they were asymp-tomatic; moreover, because an 18-month period may not allow suffi-cient time to observe root maturogenesis, follow-up of all patients inthis study is ongoing.

On the basis of the hypothesis that treatment outcome may beaffected by the extent of periapical pathology, with larger lesionsrequiring more time for apical closure or bony healing, teeth in thepresent study were assessed according to size of radiolucency. A


Clinical Research

number of previous studies (12, 14, 29) reported a possiblerelationship between the duration of pulp necrosis and treatmentoutcome and suggested that longstanding infection might destroycells capable of pulp regeneration. Although large periapicallesions could be indicative of an extended period of pulp necrosis,the present study found no significant difference in treatmentoutcomes by lesion size.

A conventional apexification study has reported a correlation be-tween acute symptoms such as spontaneous pain and night pain and adelay in root closure (30). Although another study reported no corre-lation between pretreatment symptoms and barrier formation time(31), that study made no differentiation between acute and chronicsymptoms. In the present study, apical closure time was significantlylonger in patients with preoperative acute symptoms; however, thisfinding cannot be compared with other RET studies because this issuehas not been previously mentioned.

With respect to innervation, in the present study, 5 teeth in the PRPgroup and 2 teeth in the BC group were rated ‘‘excellent’’ because ofpositive responses to vitality testing. Previous studies have also reportedpositive responses to cold and/or electric pulp testing after RET (4, 8–10, 15, 16). Hargreaves et al (4) stated that positive responses to pulpsensitivity tests after RET are an indication that previously vacant spacemay become occupied by innervated tissue. In this study, less than 50%of all teeth showed a positive response to pulp testing. This may be dueto the criteria used to define vitality (ie, a positive response to both coldand EPT tests). It is also possible that as suggested by Johns and Vidya-nath (32), negative responses to vitality testing may be attributed to thethick layers of MTA (3–4 mm) and glass ionomer cement (2 mm), fol-lowed by permanent restoration. Moreover, dentin sensitivity in the nat-ural pulp-dentin complex is related to the hydrodynamic activity ofdentin tubules in association with A-b sensory fibers, whereas newly re-generated, mineralized root canal tissue does not appear to have well-organized dentin tubules and thus may not exhibit the same sensitivity asnatural tissue (3).

In the present study, 8 teeth (PRP, 4; BC, 4) showed pulp canalobliteration. Varying degrees of obliteration have been previously re-ported in RET (8, 14, 15). This may be related to the osteoinductiveactivity of MTA (33). Shah et al (34) stated that obliteration afterRET could be a sign of calcification of the entire canal, which couldmake future endodontic treatment more difficult. However, the major-ity of the literature does not support endodontic intervention in thecase of mineralized obliteration unless periradicular pathosis is de-tected or the involved tooth becomes symptomatic (2, 35).

Recent reports (18, 36) have reported successful RET withcefaclor used in place of minocycline in the triple antibiotic paste toavoid discoloration. Therefore, the present study not only usedcefaclor instead of minocycline, it also used a dentin bonding agentto seal the dentinal walls of the access cavity as a precaution againstdiscoloration, which was not observed in any patient. However,discoloration of the crown after MTA placement was a commonconsequence. MTA is widely used as a coronal plug in RET; however,crown discoloration represents a potentially serious complication,especially in anterior teeth (2), and other studies have successfullyused biocompatible MTA-like cements or glass ionomer cement instead(2, 8, 34, 37). These materials may be preferable for more aestheticresults, especially when anterior teeth are involved.

ConclusionPRPwas found to be useful in constructing a scaffold for RET; how-

ever, treatment outcomes did not differ significantly between PRP andconventional BC scaffolds.


AcknowledgmentsThe authors thank Ms Deborah Semel Demirtaş for proof-

reading the manuscript.The authors deny any conflicts of interest related to this

study.

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Efficacy of Platelet-rich Plasma as a Scaffold in Regenerative Endodontic TreatmentMaterials and MethodsTreatment ProceduresClinical and Radiographic ExaminationsStatistical Analysis

ResultsPreoperative Clinical and Radiographic FindingsPostoperative Clinical and Radiographic FindingsTreatment Outcomes

DiscussionConclusionAcknowledgmentsReferences

efficacy of platelet-rich plasma as a scaffold in...

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