Deep Caries & Pulp Mx of Primary Teeth

Question 1

What are some dental factors to consider during pre-operative assessment?

Answer 1

1. General dental condition (e.g few carious teeth needing pulp therapy)
2. Restorability of tooth:
   - Internal/external resorption
   - Exposed root => resto process might damage successor
   - Caries through pulpal floor
   - Pulp calcification
3. Lifespan of tooth (e.g close to exfoliation)
4. Amount of supporting bone
5. Significance of tooth to dental arch (e.g loss of E => space loss)
6. Absence of successor => might want to conserve primary tooth

Question 2

What is the preventive only approach?

Answer 2

• Slow down & arrest caries using preventive measure (e.g topical fluoride)
• Caries initial/minimal or can be made self-cleansing (e.g disking)
• Require px & parental compliance => attend regular visits

Question 3

What is the biological approach?

Answer 3

• Incomplete caries free, place resto w good seal => arrest remaining caries
• e.g Hall technique, ITR, IPC

Question 4

How can we come to a diagnosis of pulp status in primary teeth?

Answer 4

1. Pain history (SOCRATES)
2. Clinical Examination
   - discolouration
   - redness, swelling, sinus tract
   - mobility
3. Vitality tests
   - percussion
   - cold test
   - EPT not valid, response inconsistent
4. Radiographs
   - pathologic root resorption
   - pathology at apical/furcal areas
   - bone loss
   - pulpal calcification
5. Bleeding from exposed pulp during procedure
   - Pink/red & healthy => little bleeding
   - Dark red/purple & necrotic => oozing

Question 5

What are the types of pulp therapy?

Answer 5

Vital pulp therapy, for
- normal pulp
- reversible pulpitis

Non-vital pulp therapy, for
- irreversible pulpitis
- necrotic pulp

Question 6

What are the clinical parameters that should be observed for teeth indicated for vital pulp therapy?

Answer 6

• No spontaneous pain
• Pain from thermal testing does not linger
• NTTP, NTTPp, mobility WNL
• No soft tissue lesions (e.g swelling, sinus)
• No PARL/perifurcation on radiograph

Question 7

What are the indications for Hall Technique?

Answer 7

• Vital tooth
• If unable to do conventional resto for carious primary molars

Question 8

Describe the Hall Technique

Answer 8

1. Place separator at previous visit to make space for crown
2. No LA, caries removal or tooth prep
3. Cement preformed SSC with GIC – seal in decay

Question 9

What is the rationale behind a protective base and what are some examples?

Answer 9

• Cover exposed dentinal tubules => Prevent microleakage & post-op sensitivity
• Protective barrier btw resto material/cement & pulp => Preserve tooth vitality, promote pulp healing & tertiary dentine formation

Examples of bases: Ca(OH)2, GIC

Question 10

What is the indication for indirect pulp cap?

Answer 10

Vital asymptomatic tooth with deep caries adjacent to pulp

Question 11

Describe the procedure for indirect pulp cap

Answer 11

1. Place biocompatible material over thin residual layer of affected dentine – stimulate healing and repair (eg Ca(OH)2, ZOE, RMGIC, MTA)
2. Restore tooth with material that seals against microleakage (eg CR)
   >90% success rate at 3 years follow up

Question 12

What are the indications (including pulpal status) for interim therapeutic restoration (ITR)?

Answer 12

• When conventional cavity prep & restorations not feasible (eg uncooperative child/special needs, partially erupted teeth)
• For caries control in child patients with multiple open carious lesions who would benefit from step-wise excavation or awaiting rehabilitation under GA
• Normal pulp/reversible pulpitis

Question 13

Describe the procedure for ITR

Answer 13

1. Caries removal, deepest carious dentine left so as to not expose pulp (different from IPC)
2. Total/maximum caries removal at periphery of lesion
3. Restore with GIC
4. Monitor for s/s, decide if need to re-excavate caries & replace with conventional resto later on

Question 14

What are the indications for direct pulp cap?

Answer 14

• Pin point mechanical exposure during cavity prep or following a traumatic injury
• NOT for carious pulp exposure
• Vital tooth

(rarely done for primary teeth)

Question 15

What are clinical parameters to take note of that indicate success of vital pulp treatments (IPC, DPC)?

Answer 15

• Check that tooth remains vital
• No post tx s/s
• No radiographic evidence of pathologic changes
• No harm to succedaneous tooth

Question 16

What are 3 possible ideal outcomes of pulpotomy?

Answer 16

• Preserve radicular pulp in healthy state
• Render radicular pulp inert
• Encourage tissue regeneration & healing at site of radicular pulp amputation (best!)

Question 17

What are the indications for pulpotomy?

Answer 17

• Carious/mechanical/traumatic pulp exposure in primary tooth
• Inflammation/infection deemed to be confined to coronal pulp & radicular
  pulp deemed to be vital => able to control bleeding

Question 18

Describe the procedure for pulpotomy?

Answer 18

1. Baseline x-ray & vitality tests
2. Clean tooth, LA, RDI
3. Caries free & remove pulp chamber roof
4. Amputate coronal pulp (~2mm):
   - Spoon excavator/high speed round bur (slow speed might catch pulp)
   - Go down along the side until reach pulp chamber floor
5. Irrigate w saline & dry w cotton pellet
6. Assess bleeding:
   - Healthy red bleeding, can achieve haemostasis
   - Dark red/purple, cannot achieve haemostasis => pulpectomy
7. Place medicated CP over amputated pulp stumps for 3-5min:
   - Minimal amount of medicament (formocresol) => avoid cytotoxicity
   - Soak CP in 1 drop of medicament & squeeze w gauze until damp
8. Place ZOE/GIC/IRM to fill pulp chamber
9. Restore tooth (Ideally SSC)

Question 19

What is the F/U Mx of pulpotomy of primary tooth?

Answer 19

F/U 6/12 with annual radiograph
Success rate of formocresol/MTA pulpotomy 90-95%

Question 20

What are the possible complications following pulpotomy?

Answer 20

• Premature exfoliation
• Pulpal calcification
• Internal resorption
• Enamel defects in succedaneous teeth
  (e.g Turner’s hypoplasia)

Question 21

What are some medicaments used for pulpotomy?

Answer 21

• 1/5 dilution of formocresol (19% formaldehyde, 35% cresol)
• Ferric sulphate
• Mineral trioxide aggregate (MTA)

Question 22

What are the effects of formocresol?

Answer 22

• Possible toxicity, diffusion into systemic system, potential mutagenicity & carcinogenicity => diluted for use
• 1/5 dilution vs non-diluted:↓ PA & furcation RL, ↓ tissue irritation, ↓ cytotoxicity
• Equally effective, high success rate

Question 23

What is the mode of action of ferric sulphate?

Answer 23

• Ferric ion complex seals cut blood vessels => haemostasis
• Very acidic
• Success rate similar to formocresol

Question 24

What are the features and effects of MTA?

Answer 24

• Biocompatible, prevent microleakage & promote tissue healing
• Expensive, may discolour teeth (not too bad cos will exfoliate)
• Success rate equal/higher than formocresol

Question 25

What are difficulties faced when doing pulpectomy for primary teeth?

Answer 25

- Variable & complex root morphology - Thin canal walls & pulpal floor - Ongoing physiological root resorption - Proximity of underlying developing permanent teeth

Question 26

Describe the procedure for pulpectomy

Answer 26

1. Baseline x-ray & vitality tests 2. Clean tooth, LA, RDI 3. Caries free & remove pulp chamber roof 4. Remove radicular pulp (without enlarging canals) 5. Flush with NaOCl/CHX/sterile water/saline 6. Establish WL with radiograph 7. Use files to gently debride canals 2mm short of radiographic apex 8. Dry canals with paper points 9. Fill canals with appropriate resorbable material 10. Take radiograph to assess density & level of root fill 11. Place cement base & permanent resto 12. Recall 1 week, 3 months, 6 months, then annually until tooth exfoliates

Question 27

What are the ideal properties for root canal filling material for primary teeth

Answer 27

- Antiseptic - Adhere to canals - Does not shrink - Does not discolour teeth - Harmless to periapical tissues and tooth germ - Resorb with root of primary tooth

Question 28

What are some root canal filling materials that can be used?

Answer 28

- ZOE (resorb slower than tooth but inconsequential) - Iodoform - Ca(OH)2 w Iodoform (Vitapex)

Question 29

What are some complications after pulpectomy?

Answer 29

- Possible flare up => redo RCT if have s/s - Premature exfoliation - Over-retention - Enamel defects in succedaneous teeth

Question 30

What are the indications for lesion sterilisation / tissue repair (LSTR)

Answer 30

When the primary tooth is to be maintained for less than 12 months

Question 31

Describe LSTR

Answer 31

Similar to pulpect but no instrumentation of root canals 1. Canal orifices enlarged slightly using large round bur 2. Walls of pulp chamber cleaned with phosphoric acid, rinsed and dried 3. A/B paste (clindamycin, metronidazole, ciprofloxacin) applied onto enlarged canal orifices & pulpal floor 4. Cover with GIC and restore with SSC