25244_emd vs fc pulpotomy

8/6/2019 25244_EMD vs FC Pulpotomy

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COMPARISON OF PULPAL RESPONSE FOLLOWING

PULPOTOMY PROCEDURE USING ENAMEL MATRIX

DERIVATIVE VERSUS FORMOCRESOL IN PRIMARY

DENTITION

Ahmed A. Mohamed*, Maha M. F. Mounir **, Nadia A. Wahba***, Omar A. S. El-

Meligy****, Jumana M. S. Sabbarini*****

ABSTRACT

The aim of the present study was to compare the clinical, radiographical and

histological effect of enamel matrix derivative (Emdogain®) versus formocresol on

pulpotomized human primary teeth.

Clinical follow-up of formocresol treated teeth at 2 months revealed (93.3%)

clinical success rate. Only one tooth suffered from pain and was sensitive to

percussion in formocresol group. This dropped to 86.7% at 4 months. At 6 months

five teeth showed pain and pain on percussion clinically lowering the clinical

success rate to 66.7%. Emdogain® showed an overall clinical success rate of 100%

at 2 & 4 months. Only one tooth was reported with pain on percussion at 6 months

reducing the clinical success rate to 93.3%. All teeth (100%) were free from

mobility, abscess formation or draining sinus at 2, 4 & 6 months among bothFormocresol and Enamel Matrix Derivative (Emdogain®) tested groups.

Radiographically in Formocresol group, eleven teeth (73.3%) showed no

pathological signs at 2 months recall. The radiographic success rate dropped to four

teeth (26.7%) at 4 months recall. Two teeth only (13. 3%) were still free at 6 months

recall. Emdogain® group showed radiographic success rate of 86.7% representing

thirteen free teeth. This succes rate dropped to ten teeth (66.7%) at 4 months follow-

up. Nine teeth (60%) were still frees of pathological signs at 6 months. Histological

evaluation seemed far more promising for Emdogain® than formocresol. When the

pulp wound was exposed to EMD, a substantial amount of reparative dentin-liketissue was formed in a process much resembling classic wound healing with

moderate inflammatory infiltrate beneath the injury with subsequent increase in

angiogenesis of normal pulp tissue.--------------------------------------------------------------------------------------------------------------

*Professor of Pediatric Dentistry and Dental Public Health, Faculty of Dentistry, Alexandria University.

**Professor of Oral Biology, Faculy of Dentistry, Alexandria University.

***Associate Professor of Pediatric Dentistry, Faculty of Dentistry, Alexandria University.

****Lecturer in Pediatric Dentistry, Faculty of Dentistry, Alexandria University.

*****

Pediatric Dentist, Ministry of Health, Irbid, Jordan.

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At later stages, a fine web of odontoblast-like cells was also observed growing from

the central parts of the pulp towards the pulp chamber walls forming a dentin bridge.

The EMD induced hard tissue closely resembled osteodentin early in the process,

but later on the hard tissue became more like the secondary dentin. On the contrary,

the severe chronic inflammation of pulp tissue acccompained with formocresoleventually produced pulp necrosis with or without fibrosis and incomplete dentin

bridging at terminal stages in some cases.

Based on the present findings, it may be concluded that Emdogain® is a bio-

inductive material that is compatible with vital human tissues. It offers a good

healing potential and is capable of inducing dentin formation, leaving the remaining

pulp tissue heathy and functioning.

INTRODUCTION

Pulpotomy is removal of the coronal portion of the pulp. It is an accepted

procedure for treating primary teeth with carious pulp exposure. The abnormal tissue

can be removed, and the healing can be allowed to take place at the entrance of the

pulp canal in an area of essentially normal pulp(1).

Historically, pulpotomy therapy for primary dentition has developed along three

lines: devitalization, preservation and regeneration. Devitalization, where the intent

to destroy vital tisue is typified by formocresol and electrocautery. Preservation, the

retention of maximum vital tissue with no induction of reparative dentin bridge is

exemplified by glutaraldehyde and ferric sulfate treatment. Regeneration, the

stimulation of dentin bridge, as long been associated with calcium hydroxide. Of the

three categories, regeneration is expected to develop the most rapidly in coming

years(2).

As for devitalization, the use of formocresol as pulpal medicament was first

introduced in the early twentieth century(3), and has since been a popular choice for use in pulpotomy procedures, mainly because of its ease of use and clinical success.

Even though the use of this pulpotomy medicament is common and produces very

successful results, concerns regarding its use have led investigators to search for a

safe and effective alternative(4). These concerns were represented by many studies.

One is a study by Magnusson (1978)(5), in which therapeutic pulpotomies in primary

molars with formocresol technique were studied by systematic follow-up. The

results showed that the radiographic follow-up revealed periradicular osteitis in 10%

of treated teeth. Internal root resorption was seen in 37% of teeth. The histological

examination revealed a very capricious diffusion of the medication throughout the pulp tissue. Vital pulp remnants in the apical part of treated roots showed no signs of

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healing. Pulps presented a varying number of inflammatory cells in the border zone

adjacent to the formocresol-fixed region. In 80% of roots histological sections

revealed signs of internal resorption. Another study by Ranly & Gracia-Gody (2000)(6), concluded that although rationale for the use of formocresol is not clear, it

presumably fixes affected and infected radicular tissue, so that a chronicinflammation replaces an acute inflammation. Other concerns have been raised

regarding the toxicity and potential carcinogenicity of formocresol in humans(7).

As for regeneration, the stimulation of dentin bridge, has long been associated with

calcium hydroxide which is considerably less harsh on pulp tissue than

formocresol(6). It is believed that high pH of calcium hydroxide based materials

causes frequent side effects such as internal resorption and necrosis, which

prevented their acceptance as universal indicators for reparative dentin formation in

primary dentition

(8)

.

Recently, a number of studies have reported that various odontogenic proteins can

induce reparative dentin formation. Biologically active molecules, such as the bone

morphogenic protiens (BMPs)(9), the osteogenic protein (OP-1)(10), or biometrics,

such as the demineralized dentin(11), have all been proposed as specific bioinducers

of dentin formation. None of the biomaterials/proteins are commercially available,

nor are their safety and toxicity aspects properly assessed for the use in clinical

trials(9,10,11).

(Enamel matrix proteins) like amelogenins from the pre-ameloblasts, are

translocated during odontogenesis to differentiating odontoblasts in dental papilla,

suggesting that amelogenins may be associated with odontoblast changes during

development(12). Enamel matrix derivative (EMD), obtained from embryonic enamel

of amelogenin, was demonstrated in vitro, using a wound healing model, to be

capable of stimulating periodontal ligament cell proliferation at earlier times (i.e.,

days one to three) compared to gingival fibroblasts and bone cells(13).

Heijl et al (1997)(14), led a clinical trial on enamel extracellular matrix proteins in

form of the enamel matrix derivative, EMD commercially presented asEMDOGAIN® which has been successfully employed to incite natural

cementogenesis to restore a fully functional periodontal ligament, cementum and

alveolar bone in patients with advanced peridontitis.

The ability of EMD to facilitate regenerative processes in mesenchymal tissues is

well established. The EMD-induced processes actually mimic parts of normal

odontogenesis, and it is believed that the EMD proteins participate in the reciprocal

ectodermal-mesenchymal signaling that control and pattern these processes(15).

Based on these observations, it has been suggested that amelogenin participates inthe differentiation of odontoblasts and the subsequent predentin formation(16).

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Nakamura et al (2001)(17), demonstrated that EMD quickly induced a large amount

of new dentin-like tissue when applied as direct-capping material onto the exposed

pulp tissue of permanent molar teeth in adult miniature swine. The pulp wound

showed features of classic wound healing. Subjacent to the healing wound, a bridgeof new hard tissue was formed, sealing off the wound from the healthy pulp tissue.

The pulp tissue subjacent to this new hard tissue was invariably free of all signs of

inflammation. Moreover, a layer of odontoblast-like cells had formed, abutting the

newly formed mineralized tissue.

Nakamura et al (2002)(8), in another study designed to examine whether EMD could

induce reparative dentin formation without eliciting adverse side effects in

pulpotomized teeth in miniature swine. The results demonstrated the potential of

EMD as a biologically active pulp dressing agent that specifically induces pulpalwound healing and dentin formation in the pulpotomized teeth without affecting the

normal function of the remaining pulp. Furthermore, it was reported that growth of

some bacteria including streptococcus mutans, is inibited by the presence of EMD.

Ishizaki et al (2003)(18), examined the histopathological response of dental pulp

tissue to EMD used in pulpotomized teeth of mongrel dogs. The treated teeth

histologically demonstrated an increase in tertiary dentin, suggesting that EMD

exerts a considerable influence on odontoblasts and endothelial cells of capillaries in

dental pulp tissue. These results imply that EMD used as pulp treatment material

plays a role in the calcification of dental pulp tissue.

Olsson et al (2003)(19), led a study on the effect of EMD gel on experimentally

exposed human pulps and registered postoperative symptoms. After twelve weeks,

EMD gel demonstrated extensive amounts of hard tissue that was formed along side

the exposed dentin surfaces and in patches in adjacent pulp tissue. Moreover,

postoperative symptoms were less frequent.

Based on these experiments, Emdogain® gel has several potential clinical

applications and shows promising results as a valuable material for use in pulpotomy procedures especially in primary dentition. However, more experimental data and

further human research is needed, before emdogain® gel can be developed as a

material for predictable induction of dentin formation, which seems a reasonable

challenge that is worthy of investigation.

The aim of this study was to compare the clinical, radiographic and histological

effect of Enamel Matrix Derivative (Emdogain®) versus formocresol on

pulpotomized human primary teeth.

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MATERIALS AND METHODS

A- Clinical study:

This study was carried out on children served by the pediatric dental clinics,

Department of Pediatric Dentistry, Faculty of Dentistry, Alexandria University.Fifteen patients with an age range of 4 to 7 years, with bilateral deep carious

mandibular primary molars, were selected to meet the criteria recommended for

pulpotomy, with no contraindications to pulpotomy in their medical history.

The criteria for tooth selection in this study were:

1- Primary molars with vital carious pulp exposures that bled upon entering the pulp

chambers.

2- No clinical symptoms or evidence of pulp degeneration, such as pain on

percussion, history of swelling, or sinus tracts.3- No radiographic signs of internal or external resorption and no periapical or

furcation radiolucency.

4- Teeth would be restorable with posterior stainless steel crowns.

The thirty selected teeth were randomly divided into two treatment groups of

fifteen teeth each.

Group I (FC group): In which the pulpotomized teeth were treated with

formocresol(Buckley’s, Sultan Chemists Inc., Englewood,NJ,U.S.A.) on one side of

the mandible.

Group II (EMD group): In which the pulpotomized teeth were treated with

Emdogain® (BIORA AB, Malmo, Sweeden) on the contra-lateral side of the

mandible.

Following profound local anaesthesia and rubber dam application, a high sterile

high-speed bur was used to remove the roof of the coronal pulp chamber. The

coronal pulp tissue was amputated using a sterile sharp spoon excavator. Pulpal

hemorrhage was controlled by moist cotton pellet.

In group I (FC group): A sterile cotton pellet lightly moistened with formocresol

(1/5 conc.) then blotted, was placed against pulpal stumps for 5 min.

In group II (EMD group): Amputated pulpal stumps were covered with Emdogain®gel.

In all treated teeth, Cavit® (3M ESPE, Germany) base material was placed over

treated pulps, followed by a layer of light cured glass ionomer cement. Finally

treated teeth were restored with stainless steel crowns.

The children were recalled for clinical and radiographic evaluations after two, four

and six months. Clinical success was judged using the following criteria: (1) No pain

on percussion, (2) No abscess or fistulation, (3) No pathologic tooth mobility.Radiographic success was judged using the following criteria: (1) Presence of

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normal periodontal ligament space, (2) Absence of pathologic root resorption, (3)

No canal calcification or periradicular radiolucency.

B- Histological study:

Fourteen carious primary canines indicated for pulpotomy were selected among

teeth deemed for serial extraction. These teeth were subjected to the same

pulpotomy procedures as previously mentioned in (FC group) and (EMD group).

Teeth were extracted after one week, two weeks and six months to compare and

asses the response of the pulp to both formocresol and Emdogain® gel. After

extraction, teeth were fixed in 4% neutral buffered formaline, then apical foramina

were occluded with wax. Demineralization was performed in 5% trichloro-aceticacid. Longitudinal serial sections of (5μm) were prepared, processed and stained

with Haematoxylin & Eosin and Trichrome stain. The specimens were examined

under light microscope to assess histological response of the treated pulpal tissue.

Each specimen was observed for pulp vitality, pulp inflammation, odontoblastic

layer integrity, dentin bridge formation and calcific deposits. Series of sections

containing pulp tissue were observed under light microscope equipped with a digital

camera (Olympus Micro-Image, Maryland, U.S.A.) and computerized for

histometric analysis(8).

Clinical and radiographic data was collected, tabulated and statistically analysed .

RESULTS

The clinical study consisted of fifteen patients with bilateral pulpotomized

mandibular primary molars for clinical and radiographic evaluation. They were

chosen according to the previously determined criteria. The mean age was 5 years ±

0.73. They were five females and ten male patients. The treated teeth comprised

twenty two lower first primary molars and eight lower second molars. Teeth of both

groups were checked clinically one week post-operatively. At this time, no

pathological signs or symptoms were reported in any of the treated teeth.

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1- Clinical results

At 2 months, on clinical examination only one tooth suffered from pain and was

sensitive to percussion in the formocresol group. This accounts for (93.3%) clinical

success rate. This dropped to 86.7% at 4 months. At 6 months five teeth showed painand pain on percussion clinically, lowering the clinical success rate to 66.7%.

Emdogain® showed an overall clinical success rate of 100% at 2&4 months. Only

one tooth presented with pain on percussion at 6 months reducing the clinical

success rate to 93.3% .

All teeth (100%) were free from mobility, abscess formation or draining sinus at 2,

4 & 6 months among both Formocresol and Enamel Matrix Derivative (Emdogain®)

tested groups (Table 1).

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Table (1): Comparison between Formocresol and Enamel Matrix Derivative

(Emdogain®) as regards to clinical success at 2, 4 & 6 months follow-up

Clinical

success

FC EMD P-Value of

Mc NermaYes No Yes No

2M

n 14 1 15 01.00

% 93.3 6.7 100 0

4M

n 13 2 15 00.50

% 86.7 13.3 100 0

6M

n 10 5 14 10.13

% 66.7 33.3 93.3 6.7

M = Months.

FC = Formocresol.

EMD = Enamel Matrix Derivative (Emdogain®).

2- Radiographic results

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In the formocresol group eleven teeth (73.3%) showed no pathological signs at 2

months recall. The radiographic success rate dropped to four teeth (26.7%) at 4

months recall. Two teeth only (13.3%) were still free at 6 months recall.

Emdogain® group showed radiographic success rate of 86.7% representing thirteen free teeth at 2months recall. This success rate dropped to ten teeth (66.7%) at 4 months follow-up. Nine teeth (60%)

were still free of pathological signs at 6 months.

The radiographic success rates for FC tested group at four and six months were

26.7% and 13.3%,respectively , and for EMD tested group they were 66.7% and

60% respectively . Statistically significant difference was evident between FC and

EMD groups at four months recall (P=0.03). Likewise, a statistical significant

difference was evident between the tested materials at 6 months recall (P=0.04)

(Table 2).

Figures (1-6) shows periapical radiographs of lower second primary molars of the

same patient treated with formocresol ( on the left side ) and Emdogain® ( on the

right side ).

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Table (2): Comparison between Formocresol and Enamel Matrix Derivative

(Emdogain®) as regards to radiographic success at 2, 4 & 6 months

follow-up

Radiographic

success

FC EMD P-Value of

Mc NermaYes No Yes No

2M

n 11 4 13 20.63

% 73.3 26.7 86.7 13.3

4M

n 4 11 10 50.03*

% 26.7 73.3 66.7 33.3

6M

n 2 13 9 60.04*

% 13.3 86.7 60 40

M = Months.

FC = Formocresol.

EMD = Enamel Matrix Derivative (Emdogain®).

* Significant at 5% level.

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Figure (1): At 2 months no radiographic

changes after formocresol

pulpotomy


changes after Emdogain®

pulpotomy

Figure (3): At 4 months PDL widening after

formocresol pulpotomy


changes after Emdogain®

pulpotomy

Figure (5): At 6 months furcation

radiolucency (↑), periapical

radiolucency (↑), internal

resorption (↑) after

formocresol pulpotomy

Figure (6): At 6 months no radiographicchanges after Emdogain®pulpotomy

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Histological results

At 7 days Emdogain®, the amputated pulpal surface is lined by a thin nearly

continuous cellular layer. Generalized congestion accompanied by an increase in

angiogenesis is evident in the deeper parts of the pulp tissue below application sites.Moderate inflammatory cell infiltration is seen within the otherwise normal pulp

architecture.A nearly continuous layer of odontoblast cells line dentin cells.

At 7 days Formocresol, residual formocresol line the amputated pulpal surface.

Generalized congestion accompanied by moderate inflammatory infiltration of pulp

tissue is seen. A discontinuous odontoblastic layer line dentin walls.

At 14 days Emdogain® the amputated pulpal surface is lined by a thin, continuous

cellular layer. Increase in angiogenesis and congestion are persistent in nearly mostof the specimen. Mild to moderate inflammtory cells infiltrate. One specimen few

resorption lacunae in the walls of dentin.

Generalized homogenous collagenous deposition is seen within the pulpal matrix.

Most of the teeth showed small islands of dentin-like tissue at different stages of

mineralization. Some of these islands tend to coalesce together subjacent to the

amputation site, at the junction between vital pulp tissue and amputated superficial

part .

At 14 days formocresol, increase in congestion is noted in pulp tissue accompanied

by mild to severe inflammatory cell infiltrate. Discontinuity of odontoblastic cell

layers lining dentin walls and increase in fibrous content of pulp tissue is also noted.

At 6 months/24 weeks Emdogain®, most of the teeth showed coalescing island of

dentin-like tissue trying to bridge the full width of the coronal pulp at the interface

between the wounded and unharmed pulp tissue below amputation site accompanied

by deposition of reparative dentin along site pulpal walls narrowing the pulp canal

(Fig. 7). pulp tissue shows inflammatory infiltration.

Few teeth showed the amputated pulpal surfaces covered by a thick infiltrating layer

of cellular condensation accompanied by massive deposition of reparative dentin parts of the whole pulpal wall both coronal and apical (Fig. 8a,b). Inflammatory cell

infiltration is moderate in coronal pulp and decreases apically.

Only one tooth showed small coalescing dentin islands covering the surface of

amputated pulp not completely bridging the site. The pulp tissue is homogenous and

shows small areas revealing signs of partial degeneration. Dentin walls shows

resorption lacunae covered by predentin (Fig. 9).

At 6 months/24 weeks formocresol, partial bridging of dentin is seen together with

coronal pulp necrosis. chronic inflammatory infiltration, increase in fibrous content

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of pulp and pulpal degeneration is also seen. nearly complete absence of odontoblast

cells are recognized.

Quantitative analysis of new hard tissues

When the thickness of dentin bridges formed in EMD-treated teeth after 24 weeksthey were assessed by histomorphometry. The mean thickness of dentin-like tissues

bridging was measured.

The results were mean thickness of dentin (mm) 0.137 ± 0.105, 0.021 ± 0.004 and 0.276 ± 0.905

in different teeth.

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6 months Emdogain®

Fig. (7): Micrograph showing deciduous canines at 24 weeks after treatment with Emodogain.

110x H&E micrograph of amputated pulp showing coalescing islands of dentin-like tissue

trying to bridge the full width of the coronal pulp at the interface between the wounded

and unharmed pulp tissue below amputation site accompanied by deposition of reparative

dentin along site pulpal walls narrowing the pulp canal.

Dentin (D), pulp (P) and dentin bridge (DB).

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D

P DB



6 months Emdogain® (Cont.)

Fig.(8a)

Fig.(8b)

Fig. (8): Micrographs showing deciduous canines at 24 weeks after treatment with Emdogain®.

H&E micrograph, of amputated pulp showing the amputated pulpal surface covered by

a thick infiltration layer of cellular condensation accompanied by massive deposition

of reparative dentin along the whole pulpal wall (a) coronally and (b) apically (↓).

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6 months Emdogain® (Cont.)

Fig. (9): Micrograph showing deciduous canines at 24 weeks after treatment with Emdogain®.

110x H&E micrograph of amputated pulp showing small coalescing dentin islands

covering the surface of amputated pulp (↓). The pulp tissue is homogenous and shows

signs of partial degeneration (*). Dentin walls shows resorption lacunae ( )

covered by predentin (PD). Dentin (D) and pulp (P).

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*

*

*

D

P

PD



DISCUSSION

Pulpotomy of the deciduous teeth is not only the most frequent endodontic

treatment performed on children, but also the most controversial. Based on the

amputation of the pulp chamber and the conservation of the inflammation-free rootcanals, the clinical results can be good, depending on the materials used. In this,

formocresol remains the reference even if its clinical toxicity is still reported in

literature on very controversial basis. Nevertheless, this was sufficient to trigger and

stimulate a search for alternatives, and led to the proposition to use several other

new materials and even most recent regenerative materials as new bases for the

treatment of the pulp stumps after coronal pulp amputation(20).

Formocresol

In the present study, clinical success rate ranged from 66.7% to 93.3%. One tooth

only showed pain through the three periodic recalls. However, two teeth showed

pain on percussion at 4months follow-up and five teeth at 6 months. One tooth was

considered to have failed clinically due to pain on percussion. The same tooth,

however, did not present any radiographic changes. Similarly, some of the teeth,

which were considered radiographic failures did not present any clinical signs and

symptoms through the 6 months follow-up. Due to the small sample size in this

study, a difference of one tooth could be significant. However, if the recall periods

were continued longer, more cases might have started to show clinical or even more

radiographic failures. Furthermore, it was reported that an 81% agreement between

clinical and histological diagnosis of chronic coronal pulpitis in carious primary

teeth exists. A tooth may appear to be a good candidate for pulpotomy clinically, but

pulpal inflammation may not be confined to the coronal portion of the pulp only,

jeopardizing the success of the procedure. The fixative properties of formocresol and

the possibility of mummifying a broad zone of the remaining pulpal tissue make a

tooth treated with this medicament still remain clinically successful(21).

In some clinical studies, the criteria of clinical failure went to the extreme and wasdetermined based on the fistula formation and even buccal swellings only, ignoring

moderate pain or even pain on percussion which gives rise to real difference in

success results (22,23).

In the present study, radiographic success rate ranged from 13.3% to 73.3% at 2,4

& 6 months follow-up. Only two teeth of fifteen were free of any radiographic

changes including periodontal membrane widening which resembles early sign of

pulpal pathosis.

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Almost all other studies ignored the PDL widening and considered it normal pulpal

change or even questionable success but not failure. Moreover, a recent study has

categorized internal resorption as radiographic success(24). In their study, Smith et al

(2000)(24), claimed that since this radiographic finding does not involve osseous

changes it would not affect the permanent successors. For this reason, it was proposed that internal resorption, as long as it is confined to the tooth, should not be

defined as failure. Of course, this gives comparatively higher radiographic success

rate. In this study, internal resorption amounted to 26.7% of pulpotomized molars

which is moderately higher than previous studies that ranged from 11% to 19% of

the treated teeth(25,26,27).

Periapical radiolucency was described in many studies as part of the pathological

external root resorption(28). Moreover, it was reported that formocresol from the

pulpotomized molars leaches into the surrounding periodontal tissue causing theradiolucency and accelerates root resorption due to chronic inflammatory reaction.

This accounts for 39% to 45% of pulpotomized molar teeth that show periapical

radiolucency with the presence of external resorption(25,29).

In this study, the furcation and perapical radiolucency ranged from 26.7% to 53.3%

of the pulpotomized molar teeth. These results coincide with the previous studies.

Pulp calcification was observed in 13% of teeth treated with formocresol after 24

months, which is similar to frequencies reported in many previous studies (25,26,27). In

the present study, only 6.7% of teeth treated with formocresol at 6 months follow-up

showed calcific degeneration. This low percentage was due to the short period of

this study. These results did not coincide with the findings of Fei et al (23) who

reported 44% of pulp calcification after application of diluted formocresol in 27

human molars. His explanation seemed logical due to less harmful effect of the

diluted formocresol, which might be keeping the pulpotomized tooth more healthy

and might as well allow a degree of odontoblastic activity.

Histological Evaluation of Formocresol

Prominent pulpal destruction was the most outstanding histological feature

accompanied by fibrosis and incomplete dentin bridging. This observation is

consistent with previous studies by Garcia-Godoy et al (1982)(30), and Hill et al

(1991)(31), implying that the use of formocresol results in pulpal inflammation and

necrosis.

Some authors consider signs of dentin bridging as an indicator of healing

process(30)

. The severe chronic inflammation of pulp tissue accompanying

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formocresol will eventually proceed to pulp necrosis with or without fibrosis in

almost all cases. This is consistent with the present study.

Emdogain®

In this study, the percentage of clinical success rate of Emdogain® was 93.3% at 6

months where only one tooth out of fifteen showed pain. However, an outstanding

disadvantage was the gel consistency of emdogain®, which made its application

rather difficult. Moreover, it was impossible to condense any material over it.

Furthermore, the amount of the gel in 0.3 ml syringe was enough for five primary

molars. It was to be used within 2 hours or it would lose its effect. This entailed that

any remaining quantity was discarded if not used in proper time. This, of course,

should be considered when evaluating the cost effectiveness of the material.

Since scarce human clinical and radiographic information exists on the use of

emdogain® on pulpotomized teeth, its comparison with other regenerative materials

of different mode of action was found necessary.

The high clinical success rate of emdogain® coincides with the results reported on

calcium hydroxide as pulpotomy material in deciduous teeth by Brown (1967) (32),

Hannah (1972)(33), and Heilig et al (1984)(34) as the reported, clinical success rates

ranging from 88.2% to 95.4%.

Massoud (2002)(35), in his study on freeze-dried bone as a regenerative pulpotomy

material showed a high clinical success rate of 93.3% coinciding with that of

emdogain®.

Radiographic results seemed far more promising for Emdogain® than formocresol.

Periodontal membrane widening was significantly decreased in Emdogain® group.

The same was true for Periapical and /or furcation radiolucencies but the difference

between the two materials was not significant.

Internal resorption was not considered a radiographic failure by some authors as

previously mentioned (24). Only 1/5 of the cases showed signs of internal resorption.

On the other hand, no pulp calcifications were reported, which might indicate a

different pattern of odontoblastic activity.

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Histological Evaluation of Emdogain®

According to Nakamura et al (2002)(8), when pulp wound is exposed to EMD,

substantial steps occur in a process resembling classic wound healing with

subsequent neogenesis of normal pulp tissues and repair of dental pulp, i.e., rapidfibrodendin matrix formation and subsequent reparative dentinogenesis. The present

study is in full agreement with Nakamura et al . At 2 weeks period, the pulp matrix

itself showed homogenous fibrous deposition together with reparative dentin islands.

The formation of new dentin started from within the pulp at some distance from the

amputated site. There was also a marked tendency for angiogenesis in the deeper

parts of the pulps indicating an increased level of cell growth and/or metabolism.

After the initial phase of healing in these teeth, at later stages, a fine web of

odontoblast-like cells was also observed growing from the central parts of the pulp

towards the pulp chamber walls forming a dentin bridge. The EMD induced hardtissue closely resembled osteodentin early in the process, but later on the hard tissue

became more like the secondary dentin. In addition, at the 6 months stage most of

the treated pulp tissues revealed characteristic morphological findings of extensive

reparative dentin formation along the root canal walls and the apex itself, narrowing

the pulp space and extending to the coronal pulp. This is in accordance with Paine &

Snead(36) and Hammarstron et al (37).

The current study revealed that the incidence of inflammation did not significantly

influence the outcome of hard tissue formation. In agreement with Nakamura et al

(2002)(8), non of the teeth treated with emdogain® showed signs of irreversible pulp

damage, but rather resembled normal wound healing including the formation of a

scab covering the amputation site, moderate inflammatory infiltrate beneath the

injury and a local increase in angiogenesis and cell proliferation. All these

descriptions also coincide with previous animal studies by Nakamura et al (2001)(17)

on miniature swine and Igarashi et al (2003)(38), on Wistar rats.

Ishizaki et al (2003)(18) reported different results in their study on molar teeth of

mongrel dogs. Congested capillaries in pulp tissue were observed in early stages.

Later on, the pulp tissues revealed characteristic morphological findings of tertiarydentin along the root canal walls accompanied by atrophic pulpal degeneration.

However, dentin bridge formation could not be reproduced in this study.

It is generally known that the ratio of surface area of tissue in contact with capping

materials relative to the remaining tissue volume is considerably higher in

pulpotomy, thus if a material can elicit unwanted side effects, it is more likely to do

so in narrow pulp canals than in the wider coronal pulp(39) eliciting necrosis and / or

internal root resorption. Few specimens showed internal root resorption in the

present study and non showed necrosis. Few degenerative changes accompanied by

20



root resorption were only seen in one specimen in the 24 weeks period while the rest

of the pulp showed signs of total pulp regeneration.

Furthermore, a recent Immunohistochemical study by Nakamura

et al (2004)(40)

, demonstrated that enamel matrix proteins were present as aninsoluble protein matrix in detectable amounts at the application site for about 4

weeks. These findings demonstrate that enamel matrix molecules have the capacity

to induce rapid pulpal wound healing in pulpotomized teeth, and suggest that the

longevity and continued presence of enamel matrix nanospheres at the application

site can be utilized to stimulate growth and repair of dentin over a period consistent

with a favorable clinical outcome. This can explain the changes of the whole enamel

matrix as early as 2 weeks towards a favourable milieu for starting mineralization

and actual formation of dentin islands. The formation of dentine islands and dentine

bridge below amputation site and along dentine walls suggests that EMD treatmentnot only stimulates pre-existing odontoblasts, but also recruits new odontoblasts of

unknown origin from the central part of the pulp through mimicking biological

mediators normally active during early dentinogenesis.

Concerning the mechanism of EMD biological action, it has been reported that

EMD increases the autocrine release of TGF-β and PDGF-BB, and enhances

alkaline phosphatase expression of periodontal ligament fibroblasts(41). Both TGF-β

and PDGF-BB are known to be associated with the onset of odontoblast

differentiation. The TGF- β expressed by odontoblasts has been reported to be

embedded within the dentin matrix and involved in tissue homeostasis andreparative dentinogenesis after pulp amputation(42,43). The PDGF-BB secreted by

macrophages at the wound site is also reported to stimulate reparative

dentinogenesis after surgical pulp exposure and direct pulp capping in rat incisor

model(41).

The mechanism underlying the induction of hard tissue formation is still not known

in detail. However, it has recently been reported that EMD induces an intracellular

cyclic-AMP signal in mesenchymal cells. This intracellular signal is followed by

secretion of autocrine growth factors and other transcription factors thatsubsequently increase proliferation and maturation of extracellular matrix secreting

cells(44). Furthermore, EMD has been shown to induce expression of integrins in

cultured fibroblast(45). Integrins are known to play important roles in mesenchymal

cell development and function. The effect of EMD on mesenchymal cells appears to

be general since different connective tissue cells react similarly to these stimuli(44,45).

These mechanisms may thus be at play also in the EMD-induced pulpal healing.

It was also reported that growth of some bacteria including Streptococcus mutans,

is inhibited by the presence of EMD

(46)

. This restriction of bacterial growth is aclinically beneficial side-effect because most pulpotomies are performed under non-

21



sterile conditions, i.e. in decayed or traumatized teeth. Thus EMD components may

not only act as signal for induction of mesenchymal cell differentiation and

maturation, but also form a stable extracelluar matrix that provide a beneficial and

protective pulp environment.

The results reported in this study strongly supported the hypothesis that certain

enamel matrix proteins, like amelogenins, participate in differentiation and

maturation of odontoblastic cells and that these enamel matrix molecules play

important role(s) during early dentin formation. When the pulp wound is exposed to

EMD, a substantial amount of reparative dentin- like tissue is formed in a process

much resembling classic wound healing with subsequent neogenesis of normal pulp

tissue(8).

Thus EMD components may not only act as a signal for induction of mesenchymalcell differentiation, maturation and biomineralization but also forms a stable

extracellular matrix that provides a beneficial and protective pulp environment.

CONCLUSION

Based on the present findings, it may be concluded that Emdogain® is a bio-

inductive material that is compatible with vital human tissues. It offers a good

healing potential and is capable of inducing dentin formation, leaving the remaining

pulp tissue healthy and functioning.

Further investigations are recommended to validate the long term human pulp

tissue response to Emdogain® as pulpotomy agent in both primary and young

permanent teeth, using larger samples and longer intervals.

REFERENCES

1-McDonald RE, Avery DR. Dentistry for the Child and Adolescent. Seventh

Edition (2000): pp 421-22.

2-Ranly DM. Pulpotomy therapy in primary teeth : new modalities for old

rationales. Pediatr Dent. 1994 Nov-Dec: 16: 403-9.

3-Spies R, Binkley CJ. The use of formocresol in dentistry: a review of

literature. Quintessence Int. 1986 Jul; 17:415-7.

22



4-Dean JA, Mack RB, Fulkerson BT, Sanders BJ. Comparison of

electrosurgical and formocresol pulpotomy procedures in children. Int J Pediatr

Dent. 2002; 12: 177-82.

5-Magnusson BO. Therapeutic pulpotomies in primary molars with theformocresol technique. A clinical and histological follow-up. Acta Odontol

Scand. 1978; 36: 157-65.

6-Ranly DM, Garcia-Godoy F. Current and potential pulp therapies for primary

and young permanent teeth. J Dent. 2002; 28: 571-6

7-Avram DC, Pulver F. Pulpotomy medicaments for vital primary teeth-Survey

to determine use and attitude in pediatric dental practice and in dental schools

through out the world. ASDC J Dent Child. 1989; 56: 426-34.

8-Nakamura Y, Hammarstrom L, Matsumoto K, Lyngstadaas SP. The

induction of reparative dentin by enamel proteins. Int Endod J. 2002;35: 407-

17.

9-Nakashima M. Induction of dentin in amputated pulp of dogs by recombinant

human bone morphogenetic proteins -2 and -4 with collagen matrix. Arch Oral

Biol. 1994 Dec; 39: 1085-9.

10-Rurtherford RB, Wahle J, Tucker M, Rueger D, Charette M. Induction of

reparative dentine formation in monkeys by recombinant human osteogenic

protein-1. Arch Oral Biol.1993; 38: 571-6.

11-Nakashima M. Dentine induction by implants of autolyzed antigen-

extracted allogenic dentine on amputated pulps of dogs. Endo Dent Traumatol.

1989; 5: 279-86.

12-Nakamura M, Bringas P Jr, Nanci A, Zeichner-David M, Ashdown B,

Slavkin HC. Translocation of enamel proteins from inner enamel epithelia toodontoblasts during mouse tooth development. Anat Rec 1994; 238: 383-96.

13-Hoang AM, Oates TW, Cochran DL. In vitro wound healing responses to

enamel matrix derivative. J Periodontol 2000; 71: 1270-7.

14-Heijl L, Heden G, Svardstrom G, Ostgren A. Enamel matrix derivative

(EMDOGAIN) in the treatment of intrabony periodontal defects. J Clin

Periodontol 1997; 24: 705-14.

23



15-Hammarstrom L. Enamel matrix, cementum development and regeneration.

J Clin Periodontol 1997; 24: 658-68.

16-Salako N, Joseph B, Ritwik P, Salonen J, John P, Junaid TA. Comparison

of bioactive glass, mineral trioxide aggregate, ferric sulfate, and formocresol as pulpotomy agents in rat molar. Dent Traumatol 2003; 19: 314-20.

17-Nakamura Y, Hammarstrom L, Lundberg E, Ekdahl H, Matsumoto K,

Gestrelius S, Lyngstadaas SP. Enamel matrix derivative promotes reparative

processes in the dental pulp. Adv Dent Res 2001; 15: 105-7.

18-Ishizaki NT, Matsumoto K, Kimura Y, Wang X, Yamashita. A

histopathological study of dental pulp tissue capped with enamel matrix

derivative. J Endod 2003; 29: 176-9.

19-Olsson H, Holst KE, Petersson K, Schroder U. Effect of Emdogain®Gel on

experimentally exposed human dental pulps. Post. 2003; 81st General session

of international association for dental research.

20-Pilipili CM, Vanden Abbeele A, Van den Abbeele K. Pulpotomy of

deciduous teeth .Rev Belge Med Dent 2004; 59: 156-62.

21-Schroder U. Agreement between clinical and histologic findings in chronic

coronal pulpitis in primary teeth. Scand J Dent Res1977; 85: 583-7.

22-Farooq NS, Coll JA, Kuwabara A, Shelton P: Success rates of formocresol

pulpotomy and indirect pulp therapy in the treatment of deep dentinal caries in

primary teeth. Pediatr Dent 2000; 22: 278-86.

23-Fei A, Udin RD, Johanson R: A clinical study of ferric sulfate as a

pulpotomy agent in primary teeth. Pediatr Dent 1991; 13: 327-32.

24-Smith NL, Seale NS, Nunn ME. Ferric sulfate pulpotomy in primary

molars: a retrospective study. Pediatr Dent 2000; 22: 192-9.

25-Hicks MJ, Barr ES, Flaitz CM: Formocresol pulpotomies in primary

molars: A radiographic study in pediatric dentistry. J Pedod 1986; 10: 331.

26-Fuks AB, Holan G, Davis JM, Fidelman E: Ferric sulfate versus dilute

formocresol in pulpotomized primary molars: long-term follow up. Pediatr

Dent 1997; 19: 327-30.

24



27-Eidelman E, Holan G, Fuks AB. Mineral trioxide aggregate vs. formocresol

in pulpotomized primary molars: a preliminary report. Pediatr Dent 2001; 23:

15-8.

28-Magnusson BO. Therapeutic pulpotomies in primary molars withformocresol technique: a clinical and histological follow-up. Acta Odont

Scand1978; 36: 157-65.

29-Fuks AB, Bimstein E. Clinical evaluation of diluted formocresol

pulpotomies in primary teeth of school children. Pediatr Dent 1981;

3: 321-4.

30-Garcia-Godoy F, Novakovic DP, Carvajal JN. Pulpal response to different

application times of formocresol. J Pedod 1982; 6: 176-93.

31-Hill SD, Berry CW, Seale NS, Kaga M. Comparison of antimicrobial and

cytotoxic effects of glutaraldehyde and formocresol. Oral Surg Oral Med Oral

Pathol 1991; 71: 89-95.

32-Brown FS: Pulal therapy for primary teeth. Aust Dent J 1967; 12: 433-6.

33-Hanna DR: Glutaraldehyde and calcium hydroxide. A pulp dressing

material. Br Dent J 1972; 132: 227-31.

34-Heilig J, Yates J, Siskin M, Turner J: Calcium hydroxide pulpotomy for

primary teeth: A clinical study. JADA 1984; 108: 775-8.

35-Massoud A: Evaluation of the pulpal response of primary teeth to three

different material following pulpotomy procedures. M.Sc. Thesis, Alex Univ

2002.

36-Paine ML, Snead ML. Protein interactions during assembly of the enamel

organic extracellular matrix. J Bone Miner Res 1997;

12: 221-7.

37-Hammaström L, Heijl L, Gestrelius S. Periodontal regeneration in a buccal

dehiscence model in monkeys after application of enamel matrix proteins. J

Clin Periodont 1997; 24: 669-77.

38-Igarashi R, Sahara T, Shimizu-Ishiura M, Sasaki T. Porcine enamel matrix

derivative enhances the formation of reparative dentine and dentine bridges

during wound healing of amputated rat molars.

J Electron Microsc (Tokyo) 2003; 52: 227-36.

25



39-Ranly DM, Garcia-Godoy F. current and potential pulp therapies for

primary and young permanent teeth. J Dent 2000; 28: 153-61.

40-Nakamura Y, Slaby I, Matsumoto K, Ritchie HH, Lyngstadaas SP.

Immunohistochemical Characterization of Rapid Dentin Formation Induced byEnamel Matrix Derivative. Calcif Tissue Int 2004;

75: 243-52.

41-Hu CC, Zhang C, Yun SS, Qian Q, Ranly DM. Platelet-derived growth

factor-BB and epidermal growth factor as pulp capping medicaments in rat

incisors. J Hard Tissue Biol 1997; 6: 121-9.

42-Nakashima M. The induction of reparative dentine in the amputated dental

pulp of the dog by bone morphogenetic protein. Arch Oral Biol 1990; 35: 493-7.

43-Tziafas D, Alvanou A, Papadimitriou S, Gasic J, Komnenou A. Effects of

recombinant basic fibroblast growth factor, insulin-like growth factor-II and

transforming growth factor-beta 1 on dog dental pulp cells in vivo. Arch Oral

Biol 1998; 43: 431-44.

44-Lyngstadaas SP, Lundberg E, Ekdahl H, Andersson C, Gestrelius S.

Autocrine growth factors in human periodontal ligament cells cultured on

enamel matrix derivative. J Clin Periodontol 2001; 28: 181-8.

45-Van der Pauw MT, Everts V, Beertsen W. Expression of integrins by

human periodontal ligament and gingival fibroblasts and their involvement in

fibroblast adhesion to enamel matrix-derived proteins. J Periodontal Res 2002;

37: 317-23.

46-Spahr A, Lyngstadaas SP, Boeckh C, Andersson C, Podbielski A, Haller B.

Effect of the enamel matrix derivative Emdogain on the growth of periodontal

pathogens in vitro. J Clin Periodontol 2002; 29: 62-72.

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