MTA is now the material of choice for apexification and apexogenesis procedures due to its advantages over calcium hydroxide. It induces the formation of dentin, cementum, and bone, has excellent biocompatibility and sealing ability, and sets in the presence of moisture. For apexification, thorough debridement and coronal sealing are critical for apical closure. Calcium hydroxide was previously used but has disadvantages like a long treatment time.

1. Apexification
By
Ahmad mostafa hussein
Demonstrator, Department of Dental Biomaterials
Faculty of Dentistry, Mansoura university
2012

2. Introduction

3. What is the difference between:
Apexification and apexogenesis
?

4. Apexogenesis
* Vital pulp therapy in an immature tooth to
permit continued root growth and apical
closure.
* Depending on the extent of pulp damage, pulp
capping or shallow or conventional pulpotomy
may be indicated.
* Materials: Ca(OH)2 (calcium hydroxide)
or MTA (mineral trioxide aggregate).
MTA is the material of choice.

5. Apexification
* Root-end closure.
* It is the induction of a calcific barrier across an
open apex.
* Materials: Ca(OH)2 (has serious disadvantages)
or MTA.
MTA is the material of choice.

6. In case of open apex
What is the treatment of:
•Reversible pulpitis
•Irreversible pulpitis or necrotic pulp
?

7. * Treatment of reversible pulpitis: apexogenesis
Note: Shallow pulpotomy has higher success
rate than conventional pulpotomy.
* Treatment of irreversible pulpitis or necrotic
pulp:
- apexification (contraindication: very short
roots
and thin walls).
- root canal treatment & surgery
(contraindication: very short roots and thin
walls).
- extraction (if very poor prognosis).

8. In case of immature open apex
How can we differentiate between:
• Normal radiolucency surrounding immature
open apex
• Pathologic radiolucency resulting from a
necrotic pulp
?

9. To differentiate between normal and pathologic
radiolucency
Comparison with the periapex of the
contralateral tooth is helpful, with the other
diagnostic tests.

10. Apexification
•Definition
•The factors most responsible for apical closure
•Causes of failure
•The materials used for apexification:
* Ca(OH)2 (calcium hydroxide)
* MTA (mineral trioxide aggregate)
MTA is the material of choice.

11. Apexification
* Root-end closure.
* It is the induction of a calcific barrier across
an open apex.
* The factors most responsible for apical closure
are thorough débridement & coronal seal.
* Causes of failure: bacterial contamination.
* Apexification involves cleaning & shaping,
followed by placement of Ca(OH)2 or MTA
to the apex.

12. Ca(OH)2
1. Advantages
2. Serious disadvantages
3. Mineralization induced by Ca(OH)2 is
affected by …………………………....
…………………………...

13. Ca(OH)2
Advantages
1) alkaline pH
2) bactericidal
3) stimulate apical calcification.
Note: The reaction of periapical tissues to Ca(OH)2 is
similar to that of pulp tissue.
Ca(OH)2 produces a multilayered sterile necrosis
permitting subjacent mineralization.

14. Ca(OH)2
Serious disadvantages
1)long treatment period, usually takes 6-9
months, & may extend up to 21 months.
2)must be replaced at monthy intervals &
removed some months after placement
before final obturation.
3)multiple visits by the patient.
4)possible recontamination may occur.
5)weaken the root dentin & the risk of teeth
fracture.

15. Ca(OH)2
Mechanism of mineralization induced by Ca(OH) 2
* Calcium ions dissociated from Ca(OH)2 are
critical for inducing the mineralization of
osteoblasts.
* Hydroxyl ions did not have any effect on the
mineralization.
* The mineralization activity of Ca(OH)2 was
higher at pH 7.4 than at pH 8.5. Mineralization
activity was higher under neutral conditions.

16. MTA
1.Advantages
2.Disadvantages
3.Uses
4.Composition
5.Types (gray MTA & white MTA)
6.Formation of hydroxyapatite
7.Manipulation
(mixing, insertion, thickness, radiograph,
moist cotton pellet, temporary restoration)
Obturation & permanent restoration

17. MTA
Advantages
1) Save treatment time. High success rate. It is the material of choice for
apexification & apexogenesis.
2) Alkaline pH, which may impart antibacterial effect on some facultative
bacteria.
3) Can induce formation (regeneration) of dentin, cementum, bone &
periodontal ligament.
4) Excellent biocompatibility and appropriate mechanical properties.
5) Excellent sealing ability.
6) Produces an artificial barrier, against which an obturating material can
be condensed.
7) Hardens (sets) in the presence of moisture.
8) More radiopaque than Ca(OH)2.
9) Vasoconstrictive. This could be beneficial for hemostasis (most
importantly in pulp capping).

18. MTA
Disadvantages
1)Long setting time (2-4 h after mixing).
2)Poor handling properties. The loose
sandy nature of the mixture causes much
difficulty for insertion & packing of MTA.
3)High cost.

19. MTA
Uses
1)Apexogenesis, direct pulp capping and
pulpotomy.
2)Apexification, and root-end filling.
3)Repair of root perforations.
4)Repair of internal and external resorption.

20. MTA
Composition
* MTA is mainly composed of 3 powder ingredients,
which are 75% Portland cement, 20% bismuth
oxide, 5% gypsum; lime (CaO), silica (SiO2) &
bismuth oxide (Bi2O3) are the 3 main oxides in the
cement.
* Portland cement is the major constituent. It is
responsible for the setting & biologic properties.
* Bismuth oxide provides radiopacity.
* Gypsum is an important determinant of setting
time.

21. * Portland cement is composed of 4 major components;
tricalcium silicate, dicalcium silicate, tricalcium
aluminate, & tetracalcium aluminoferrite.
* Tricalcium silicate is the most important constituent
of Portland cement. It is the major component in the
formation of calcium silicate hydrate which gives early
strength to Portland cement.
* Dicalcium silicate hydrates more slowly than
tricalcium silicate & is responsiple for the latter’s
strength.
* Aluminoferrite (contains iron) is present in gray MTA.
It is responsible for the gray discoloration. It may
discolor the tooth.

22. Types of MTA
Gray MTA (GMTA) White MTA (WMTA)
1. Contains aluminoferrite (contains 1. Tooth-colored, due to lower amounts
iron), which is responsible for the gray of
Fe2O3.
discoloration. It discolors both the
tooth & gingival tissue close to the
repaired root surface.
2. 2. Smaller particles with narrower size
distribution (8 times smaller than that
of GMTA).
3. 3. Greater compressive strength.
4. Produces 43% more surface 4.
hydroxyapatite crystals than WMTA
in
an environment with PBS (phosphate-
buffered saline).
5. Induced dentin formation more 5.
efficiently; high number of dentin

23. MTA
Reaction & formation of hydroxyapatite
* Hydration reaction.
* Notes: - MTA is called hydraulic silicate cement (HSC).
- It is called hydraulic cement (‫)مكتسب صلةبة تحت الماء‬
(i.e. sets & is stable under water) relying primarily on
hydration reactions for setting.
- The material consists primarily of calcium silicate.
* When mixed with water, MTA sets. The pH of MTA
increases from 10 to 12.5 three hours after mixing.
In high pH environment, the calcium ions that are
released from MTA react with phosphates in the tissue
fluid to form hydroxyapatite (the principal mineral in
teeth & bones).

24. MTA
Manipulation
Mixing: gray MTA & white MTA are mixed with supplied
sterile water in a powder to liquid ratio of 3:1 according to
the manufacturer’s instruction.
Note: Poor handling properties. The loose sandy nature of
the mixture causes much difficulty for the insertion &
packing of MTA.
Insertion: Ultrasonic-assisted condensation [the ultrasonic
vibration applied to endodontic plugger(condenser)] is
more efficient than hand condensation in:
- the apical flowing of MTA (enable better flow).
- delaying bacterial leakage (enable better adaptation).
- the production of denser MTA apical plug.

25. MTA
* Thickness: 5-mm MTA apical plug provided
reduced microleakage.
* A Radiogragh is made.
* A moist (wet) cotton pellet is placed above the
MTA (to ensure setting), & a well-sealing
temporary restoration is placed.
Note: MTA sets 3-4 h after mixing.
* The patient is recalled when MTA has set (at
least 24 hours) for obturation & placement
of permanent restoration.

26. MTA
* Complete the root canal treatment with gatta-
percha & composite resin restoration
extending below the cervical level of the tooth
to strengthen the root’s resistance to fracture.

27. MTA
Note
* The role of posts & luting agents in
reinforcing root filled immature anterior
teeth remains unclear.