7/27/2019 Journal 0807

1/39

Characterization and analyses of

acid- extractable and leached traceelements in dental cements

Presenter: PGY1J. Camilleri et al, International Endodontic Journal 2012

7/27/2019 Journal 0807

2/39

Outline

Introduction

Materials and Methods

Results and Discussion

Conclusion

7/27/2019 Journal 0807

3/39

Introduction

7/27/2019 Journal 0807

4/39

Ideal Root-end Filling Material

Well tolerated by periapical tissues

Adhere to the tooth structure

Resistant to dissolution

Promote cementogenesis

Bacteriocidal to bacteriostatic

Noncorrosive

Not stain tooth or periradicular tissue

Readily available and easy to handle Allow adequate working time, then set quickly

Radiopaque(medicolegal reasons)Grossman L: Endodontic practice, ed 7, Philadelphia, 1970, Lea & Febiger

7/27/2019 Journal 0807

5/39

Ideal Root-end Filling Material

Hydraulic nature: set and develop their properties in

a wet environment

Interest in the use of Portland cement as a root-endfilling material

7/27/2019 Journal 0807

6/39

MTA

MTA= Portland cement + bismuth oxide

Bismuth oxide is added as a radiopacifier

Desirable physical and mechanical propertiesTorabinejad et al. 1995, Islam et al. 2006, Camilleri 2008a, 2010, Nekoofar et al. 2010

Bioactive when in contact with tissue fluids

7/27/2019 Journal 0807

7/39

MTA v.s. Portland cement

The presence of bismuth oxide in MTATorabinejad & White 1995

The fineness of MTA

Dammaschke et al. 2005

The lower levels of calcium aluminate and calcium

sulphate in MTA

7/27/2019 Journal 0807

8/39

Harmful Trace Elements

Arsenic (As)

Arsenic poisoning, leading to multiple organ failure and

death

Lead (Pb) A neurotoxin that accumulates both in soft tissues and the

bones, damaging the nervous system and causing brain

disorders

Chromium (Cr) Toxic, mutagenic and cariogenic, allergic reaction

7/27/2019 Journal 0807

9/39

Harmful Trace Elements

Traces of arsenic, lead and chromium have been

reported in both grey and white MTADuarte et al. 2005, Monteiro Bramante et al. 2008, De-Deus et al. 2009, Chang et al.

2010, Matsunaga et al. 2010, Schembri et al. 2010

Raising concern: MTA is applied in contact with both

hard and soft human tissues

7/27/2019 Journal 0807

10/39

New Materials

Laboratory-grade raw materials: pure tricalcium

silicate, produced in a laboratory using the solgel

method Chun-Cheng et al. 2009

Good bioactivity

Induce apatite formation in the presence of simulated

body fluid Zhao et al. 2005, Chun-Cheng et al. 2009

Products available

Biodentine (Septodont, Saint-Maur-des-Fosses, France)

Bioaggregate (Innovative Bioceramix Inc. VerioDental, Vancouver,Canada)

7/27/2019 Journal 0807

11/39

Aim

Determination of the elemental constitution and

investigation of the total and leachable arsenic,

chromium and lead in

Portland cement

Pure tricalcium silicate

mineral trioxide aggregate (MTA) Angelus

Biodentine

Bioaggregate

7/27/2019 Journal 0807

12/39

Materials and Methods

7/27/2019 Journal 0807

13/39

Materials

Characterization of cements

Determination of acid-solubleion Cr, As and Pb content

Determination of Cr, As and Pbion release in physiological

solution

7/27/2019 Journal 0807

14/39

Materials

White Portland cement

MTA Angelus

Tricalcium silicate

Biodentin

Bioaggregate

7/27/2019 Journal 0807

15/39

White Portland cement

More expensive than the gray product

Water/Cement ratio 0.30

Content Mass %

Tricalcium silicate (CaO)3 SiO2 4575%

Dicalcium silicate (CaO)2 SiO2 732%

Tricalcium aluminate (CaO)3

Al2O3

013%

Tetracalcium aluminoferrite

(CaO)4 Al2O3 Fe2O3

018%

Gypsum CaSO4 2 H2O 210%

7/27/2019 Journal 0807

16/39

MTA Angelus

White portland cement 80% + Bismuth oxide 20%

Water/Cement ratio 0.35

7/27/2019 Journal 0807

17/39

Tricalcium silicate

(CaO)3 SiO2

Water/Cement ratio 0.35

7/27/2019 Journal 0807

18/39

Biodentin

Powder: tricalcium silicate, dicalcium silicate

Zirconium oxide as a radiopacifier

Calcium carbonate is incorporated for both its

biocompatibility and its calcium content

Liquid: calcium chloride and a

hydrosoluble polymer

The hydrosoluble polymer is based on

polycarboxylate

Calcium chloride and fine particle

sizes: Rate of the setting time

7/27/2019 Journal 0807

19/39

Bioaggregate

Main: calcium silicate oxide (Ca3(SiO4)O or Ca3SiO5)

and calcium silicate

Others: hydroxyapatite, calcium phosphate silicate,

calcite Tantalum oxide as a

radiopacifier.

Bioaggregate is free of

calcium aluminatePark e al. 2010

7/27/2019 Journal 0807

20/39

X-ray fluorescence

Chemical analysis of the cement powders and the

liquids available for mixing Biodentine and

Bioaggregate (Bio A)

Liquid: Prolene film

Powders: Mylar film

7/27/2019 Journal 0807

21/39

Determination of acid-soluble ion Cr,

As and Pb content

The total trace metal was determined using the ISO

9917-1 (2007) method

liquid

3g powder

Placed in a plastic bag

Care in an incubator at

37 and 100%

humidity for 24h

7/27/2019 Journal 0807

22/39

crushed to a very fine

powder

2g powder

placed in

[HCL]=2.4 mol/L,

50 ml

Slurry swirled,lightly stoppered

and allowed to

stand for 16 h

Centrifuged in a

tube for 10 min

Supernatant transferred to astoppered acid-washed

plastic tube

Arsenic, lead and chromium

content measured

Inductively Coupled Plasma-

Mass Spectrometer

7/27/2019 Journal 0807

23/39

Determination of Cr, As and Pb ion

release in physiological solution

15 mm

2 mm

Materials cured

for 24 h at 37

and 100%

humidity

Materials placed in 10

mL Hanks balanced salt

solution for 28 days in an

incubator at 37

7/27/2019 Journal 0807

24/39

Results and Discussion

7/27/2019 Journal 0807

25/39

Characterization of unhydrated

cements

7/27/2019 Journal 0807

26/39

MTA Angelus

Both MTA Angelus and Portland cement exhibited

similar constituents, and both had an aluminate

phase

The MTA Angelus did not contain sulphate Indicating the low to negligible presence of gypsum in the

cement

Gypsum reduce the setting timeMTA Angelus

setting time: 1015 minSantos et al. 2008, Vivan et al. 2009

7/27/2019 Journal 0807

27/39

MTA Angelus

MTA Angelus: 10.5% inclusion of bismuth oxide

20% loading reported in the MTA patent

Torabinejad and White 1995

Same can be said for ProRoot MTA

Camilleri 2008b, Belo-Reyes et al. 2009

Reduced radiopacity of MTA Angelus

Camilleri & Gandolfi 2010

7/27/2019 Journal 0807

28/39

Tricalcium Silicate Cement, Biodentine

and Bioaggregate

The tricalcium silicate cement, Biodentine and

Bioaggregate had a similar chemical composition

All lacked the tricalcium aluminate phase as claimed

by the manufacturers and verified by othersPark et al. 2010

Risk of Alzheimers when Aluminum come in close contact

with human tissues

Forbes & Gentleman 1998

7/27/2019 Journal 0807

29/39

Biodentine and BioAggregate

7/27/2019 Journal 0807

30/39

Biodentine

Biodentine liquid incorporated a chloride

Added Portland cement to accelerate the setting reaction

thus shorten the setting time

Nagataki 1995

Addition of calcium chloride to Portland cement and

mineral trioxide aggregatemarked reduction in the

setting time of the cement demonstrated

Ber et al. 2007, Wiltbank et al. 2007, Bortoluzzi et al. 2009

7/27/2019 Journal 0807

31/39

Determination of acid-soluble Cr, As

and Pb content

7/27/2019 Journal 0807

32/39

Trace Element Contamination: Acid

The ISO recommendation for maximum total arsenic

content in dental materials is set at 2 mg kg-1 ISO

9917-1 (2007)

Levels of acid-extractable arsenic below the ISO limit inprevious studies (Monteiro Bramante et al. 2008) but high in later

(Schembri et al. 2010) and current studies

Short time for the acid to be in contact with the cement

Solution should be allowed to stand for 16h

7/27/2019 Journal 0807

33/39

Trace Element Contamination: Acid

The data are expressed in ppm in other publicationsDe-Deus et al. 2009, Chang et al. 2011

Not taking into consideration the sample weight and

volume of the solution used for the extraction

Such data cannot be compared to levels of contamination

recommended by ISO standards

7/27/2019 Journal 0807

34/39

Trace Element Contamination: Acid

In the present study, all the materials tested had

higher levels of arsenic than the limit set by ISO

9917-1 (2007)

High concentrations of acids and the quantity of dissolvedsolid content Nonspecific matrix effects

7/27/2019 Journal 0807

35/39

Determination of Cr, As and Pb

release in physiological solution

7/27/2019 Journal 0807

36/39

Trace Element Contamination: HBSS

Levels of arsenic leached in water for biomaterials

based on Portland cement were reported to be low

and below what is considered to be harmfulDuarte et al. 2005

In the current study

All had very low levels of trace element contamination

when compared to Portland cement

These materials should be considered safe to use

No set limits for leachable trace elements in dental

standards

7/27/2019 Journal 0807

37/39

Conclusion

7/27/2019 Journal 0807

38/39

Dental materials based on tricalcium silicate cement

and MTA Angelus release minimal quantities of trace

elements when in contact with simulated body fluids

This indicates that the dental materials investigated

in this study are safe for clinical use

The results of acid extraction could be affected by

nonspecific matrix effects by the cement

7/27/2019 Journal 0807

39/39

Thanks for your attention!

Presenter: R1