Endodontics of the traumatized immature incisor

Question 1

Definition -
An immature permanent incisor

Answer 1

defined as one where the apex can be
considered to be open.

Question 2

Root growth

Answer 2

Divergent- Parallel- Convergent

Question 3

Challenges of non vital immature tooth

Answer 3

 Compromised crown root ratio
 Thin root dentine walls
 Lack of dentinal stop against which
root canal materials can be
condensed

Question 4

Endodontics in non vital immature
tooth

Answer 4

 APEXIFICATION
 RCT of these teeth requires a root end
closure technique to form a barrier at apex
to enable a root filling to be condensed
without going through apex
◦ Calcium hydroxide therapy to induce barrier
◦ Artificial plug (MTA)

 Different to APEXOGENESIS – when aim is
to maintain vitality and allow continued root
growth (vital pulpotomy)

Question 5

Apexification

Answer 5

calcium hydroxide (calcific barrier)

Question 6

Apexogenesis

Answer 6

Vital pulpotomy

Question 7

Apexification

Answer 7

MTA

Question 8

Diagnosis of Loss of Vitality
Signs + Symptoms

Answer 8

Pain, swelling, sinus, TTP, mobility, colour
change

Question 9

Diagnosis of Loss of Vitality
Radiographic examination

Answer 9

Periapical radiolucency (PAP), arrest of
root development

Question 10

Diagnosis of Loss of vitality
Sensibility tests

Answer 10

Negative

Question 11

Diagnosis of Loss of vitality
Any doubt of loss of vitality ?

Answer 11

delay endo Rx
◦ Review 3 mths
◦ Better prognosis if no acute abscess

Question 12

Acute Abscess- Emergency
treatment
 Ideally

Answer 12

full extirpation of pulp and dress with
non-setting Calcium Hydroxide paste

Question 13

Acute Abscess- Emergency
treatment
But if acutely tender

Answer 13

 Prescription
 Arrange appt 24 – 48 hrs
 Sedative dressing – e.g. odontopaste

Question 14

Acute Abscess- Emergency
treatment

Answer 14

Ideally… and if accutely tender…

• Apexification ie
  ◦ Calcium Hydroxide (past)
  ◦ MTA (current method)
• Regenerative Endodontic Technique

Question 15

Aims of CH Apexification

Answer 15

 Creation of a calcific barrier across the
root apex
 Allows obturation of canal

Question 16

Method of CH Apexification

Answer 16

 Repeated dressing of nonsetting
Calcium hydroxide at 3-6
monthly intervals
 Once barrier achieved remainder of canal
obturated with thermoplastic GP
 Average 9 months to form up to 3 years

Question 17

Traditional
Apexification of
immature root
canal (see imaged labelled)

Answer 17

“Plug” of coarse
mineralised tissue at
apex

Empty root canal

Question 18

Traditional
Apexification of
immature root
canal
See other images

Answer 18

Periodontal ligament
Dentine of root
Canal
“Plug” of coarse osteocementum
material

Question 19

Traditional CH Apexification

(apical closure and success rates)

Answer 19

Can see a barrier
. 90% apical closure with Ca(OH)2
* 85% success @ 5yrs for adequate root
filling

Question 20

Disadvantages of
Apexification

Answer 20

Multiple visits
Lengthy treatment - may take up to 30 mths for
barrier
Difficult technique
Position and quality of barrier unpredictable
Discolouration
brittleness (risk of cervical #)

Expensive in terms
1. Clinical time
2. Parent’s time off work
3. Missed school

Question 21

Clinical technique- MTA Barrier

Answer 21

Consent
 Isolation
 Access cavity
 Widen cervical constriction (Gates Glidden)
 Extirpation of the pulp
 Estimation of full working length (1mm short of
radiographic apex
 Preparation of root canal, sterile water / 0.5%
Milton irrigation (must avoid extrusion through
apex)
 Needle loose and 2-3mm short of working length
 Dry the root canal
 Interim Root canal dressing (CH) +RMGI

Question 22

Canal morphology

Answer 22

Cervical constriction (remove this)

Question 23

Access cavity

Answer 23

Triangular shaped access (apex towards gingival
margin
 Larger than access cavity for mature tooth

Question 24

Canal preparation

Answer 24

 Straight line access
 May be up to no 140 file
 Ultrasonic activation or bristle brush

Question 25

Canal preparation instruments

Answer 25

 Plugger  Bristle brush  Fine tip for placement of non setting Calcium

Question 26

CaOH brands

Answer 26

Hypocal, Calasept, Ultracal

Question 27

Clinical technique- MTA Barrier review onwards?

Answer 27

 Review in 1-2weeks  Obturation when  no clinical signs of PAP  no radiographic signs of PAP or evidence of healing PAP  clean dry canal

Question 28

Clinical technique apexification

Answer 28

Fine tipped MTA carrier  Ideally using microscope  Plugger marker 2 mm short of WL  Careful condensation until 4mm thickness  Clean canal walls and access (MTA stains)  Confirm placement with radiograph  When set obturate (ProRoot 2nd visit reqd) ◦ Thermoplastic GP- diverging/parallel ◦ Fibrepost

Question 29

MTA properties

Answer 29

 Hydrophilic  5 min working time, sets <4hrs  pH 12.5  Non-resorbable  High biocompatibility  Compressive strength = reinforced ZOE =EBA

Question 30

MTA Composition

Answer 30

(75% Portland cement)  Tricalcium silicate  Bismuth oxide  Dicalcium oxide  Tricalcium aluminate  Gypsum ◦ Silicate oxide ◦ Tetra calcium aluminoferrite Add Water  Colloid gel of calcium oxide in  33% calcium  49% phosphate  6% silica  3% chloride  2% carbon

Question 31

Delivery- using

Answer 31

ProRoot MTA or MTA-Angelus/ thermoplastic obturation

Question 32

Pro-root MTA

Answer 32

 75% Portland Cement  20% Bismuth oxide  5% Calcium sulfate

Question 33

MTA-Angelus

Answer 33

 80% Portland Cement  20% Bismuth oxide  Fast set

Question 34

Radiographic follow up

Answer 34

 Check radiograph immediately after RCT  Follow up visit ◦ Radiograph at 1 year

Question 35

MTA Advantages

Answer 35

 Small number of visits  Biocompatible  Low leakage  Radioopaque  Better success than CH technique Disadvantages  Cost  Discolouration with poor handling  No reinforcement of canal  Contributes to brittleness

Question 36

Restoration of immature root treated teeth

Answer 36

 Where no bleaching GP removed to cemento enamel junction  Direct composite crown build up Avoid conventional posts +/- crown can consider DT light post

Question 37

Restoration of immature root treated teeth- Why avoid conventional posts +/- crown

Answer 37

1. Short root 2. Leaves inadequate root filling 3. Fragile canal walls 4. High risk of root fracture

Question 38

DT light post

Answer 38

 Double taper system  Fibre composite post  Colour matched posts and drills  Post colour changes with water eases removal  Reinforces weak remaining tooth structure

Question 39

Failures?

Answer 39

2 photos?

Question 40

Regenerative Endodontic Technique

Answer 40

 Aims to harness potential of stem cells at apical papilla  Repopulation of root canal space by stem cells from apical papilla  Cells similar to dental pulp progenitor cells  Canal repopulated with vital tissue  Produces further hard tissue of root

Question 41

Regenerative Endodontic Technique  Advantages

Answer 41

◦ Thicker root ◦ ↓propensity for root fracture ◦ Success requires no additional treatment ◦ ↓risk of reinfection as ↓reaccess

Question 42

Regenerative Endodontic Technique  Disadvantages

Answer 42

◦ Lack of long term follow-up data ◦ Not determined stage and duration of pathosis which leads to destruction of stem cells ◦ Pulp canal obliteration may complicate future endodontics

Question 43

Technique 1 Visit 1

Answer 43

Consent  +/-LA estimate  Rubber dam isolation  Pulp extirpated with barbed broach (Working length from preop rads)  Copious irrigation (1.5% sodium hypochlorite) of canals with mild disinfectant 2mm short of apex  5ml saline flush  Dry canal and then ...

Question 44

Technique 1 Visit 1 cont.

Answer 44

 Antibiotics sealed into canal (avoid pulp chamber) mixed with sterile water ◦ Ciprofloxacin ◦ Metronidazole  Cotton pellet  GIC  Earlier protocols used TABdiscolouration ◦ Ciprofloxacin ◦ Metronidazole ◦ Minocycline

Question 45

Technique 2  Visit 2 (2-4 weeks later)

Answer 45

 If no signs/ symps of infection  Epinephrine free LA  Rubber Dam isolation  Irrigate with saline  Irrigate with 10ml 17% EDTA  Dry with paper points  Sharp instrument 2 mm beyond apex to induce bleeding to fill canal  Induce clot  Clean coronal portion  Seal with Calcium silicate cement, GI, Composite

Question 46

Technique 3

Answer 46

Follow-up  Clinical and radiographic at 6 months  Clinical and radiographic at 12 months

Question 47

RET Conclusions

Answer 47

 Root development and thickening highly unpredictable  Until tissue engineering can be translated into practice RET should be limited only to those cases where prognosis of the immature tooth is deemed to be poor with the use of the traditional approach (CH/MTA)