Pulp Therapy in the Primary Dentition

• Aims and indications for pulp therapy in the primary dentition = to maintain a disease-free primary tooth until exfoliation:

  • To maintain an intact arch
  • To avoid the physiological and psychological trauma of extraction
  • If extraction is medically contraindicated
  • No permanent successor tooth
  • Space maintenance (mixed dentition)
  • Cooperative child and carers
• Contraindications for pulp therapy in the primary dentition:

  • Uncooperative child or carers
  • Child at risk from infection (immunosuppressed or at risk from endocarditis)
  • Neglected dentition (>3 pulpotomies required)
  • Severe acute infection
  • Unrestorable crown
  • Root caries
  • >2/3 root resorption (near to exfoliation)
• A neglected dentition:

  • All teeth carious - anterior teeth have decoronated and therefore exposed the pulp chambers
  • Plaque deposits visible
  • Not suitable for pulp therapy

  
• Acute infection:

  • Large palatal swelling indicates acute infection (likely related to the D)
  • Not suitable for pulp therapy either
  • Drainage of swelling and removal of tooth = better options
  • If pulp therapy was required on other side of the arch though then that would be fine

  
• Pathology:

  • Some pathology will only show up on radiographs as it's subgingival or involving the roots - important to consider
  • Here is an example of internal root resorption and ballooning of the root canal, as well as furcal pathology (pathology in the furcation)
  • Furcal pathology = important; it's the first place the periodontal membrane space will enlarge and it has lots of nerve fibre connections to the pulp chamber

  
• The approaches to pulpotomy:

  1. Preserving the radicular pulp in a healthy state
  2. Rendering the radicular pulp inert
  3. Encouraging tissue regeneration and healing of the radicular pulp at the site of amputation
• The ideal pulp therapy:

  • Harmless to pulp and surrounding structures
  • No interference with physiological root resorption
  • Promote healing of the radicular pulp
• Aetiology of pulp disease - information specific to primary molars:

  • Microbial infection - caries gets in, approaches the pulp, bacteria are ahead of carious lesion in the dentine tubules & eventually end up in pulp
  • Progresses more rapidly in primary dentition; everything is smaller
  • Cruder diagnosis of pulp status; children not good historians, often get history from mum/dad - have to make snap decisions most times
  • If marginal ridge collapse - likely the tooth will need pulp therapy
  • Spontaneous pain = tooth beyond pulp therapy - intermittent pain = pulp therapy still possible though

  
• Types of pulp therapy:

  • Vital pulp
  • Indirect pulp therapy
  • Direct pulp cap
  • Single visit pulpotomy
  • Desensitising pulpotomy
  • Pulpectomy
  • Non-vital pulp
  • Pulpectomy
• Types of pulp therapy - vital pulp:

  • Indirect pulp therapy - seals tooth and allows the pulp-dentine complex to start fighting back against those bacteria
  • Direct pulp cap - only ever used if a child has bitten on a bur and caused a traumatic exposure - would never be used for a carious exposure
• Types of pulp therapy - vital pulp:

  • Single visit pulpotomy - expose pulp, apply a dressing to the exposure and apply stick tip to pulp stumps
  • Desensitising pulpotomy - dress exposure with a desensitising paste (contains formaldehyde though, which we're moving away from using in paediatric dentistry)
  • Pulpectomy
  • Remove non-vital pulp and obturate tooth (with something that will resorb along with the roots to allow for the tooth to exfoliate normally)
  • Only really done if pulp won't stop bleeding; want to try to keep tooth for as long as possible
• Types of pulp therapy - non-vital pulp:

  • Pulpectomy
  • Remove non-vital pulp and obturate tooth (with something that will resorb along with the roots to allow for the tooth to exfoliate normally)
  • Only really done if pulp won't stop bleeding; want to try to keep tooth for as long as possible
• Indirect pulp therapy:

  • Deep dentinal caries
  • No symptoms of spontaneous or nocturnal pain
  • No evidence of pulp exposure
  • Walls clean
  • Stained cavity floor

  If the above are evident, then indirect pulp therapy would be done:

  • Cavity preparation
  • Explore/look for exposure
  • Line cavity floor/axial wall with glass ionomer
  • Well-sealed compomer restoration
  • Preformed metal crown/Hall Crown
  • Studies show good success rates compared with pulpotomy
• Aim of pulpotomy is to remove the red, irreversibly inflamed pulp and leave behind the normal/reversible inflammation.

  
• • Top image = radicular pulp stumps after root amputation - healthy radicular pulp
  • Bottom image = coronal pulp that is bleeding excessively - doesn't stop bleeding within 2-3 mins - blood is dark - indicates that coronal pulp is irreversibly inflamed
  • Wound dressing = ferrous sulphate - alternatives = formocresol

  
• Options for a bleeding carious exposure

  
• Alternatives for vital pulp:

  • Glutaraldehyde
  • Calcium hydroxide - can't be used with inflamed pulp; will fail
  • Dentine chips - not v good
  • Modified collagen solutions
  • Electrocautary/lasers - char/burn pulp stumps to form dentine bridge - popular in Japan & India
  • Ferric sulphate - doesn't build dentine bridge
  • Bone morphogenic proteins (BMP) - expensive
  • Mineral trioxide aggregate (MTA) - needs healthy pulp - acts as dentine bridge
• Ferric sulphate pulpotomy:

  • Derived from the Ca(OH)₂ pulpotomy (haemorrhage control)
  • Styptic in nature
  • Easily obtained, but expensive, used as a haemostatic agent in restorative dentistry

  1. Deep caries with irreversible inflammation in the coronal pulp
  2. Prepare cavity - unroof the pulp chamber and remove coronal pulp, leaving behind just the radicular pulp
  3. Apply 15.5% ferric sulphate for 15 seconds to cause further haemostasis - then remove cotton wool and gently dry the area with more cotton wool
  4. Add a layer of zinc oxide eugenol and top with GIC
  5. Place a preformed metal crown on top

  
• No other effect on the pulp, just forms the clot to block off the rest of the pulp so that it can remain vital.

  
• Calcium hydroxide:

  • Many different preparations tested
  • Stimulates calcific barrier
  • Healing or irritation
  • Calcific barrier forms from irritated pulp due to being beside calcium hydroxide
  • Leads to the pulp walling itself off from the calcium hydroxide by forming a dentine bridge
  • Internal resorption - not commonly found if tooth seems healthy
  • If radicular pulp or radicular pulp stumps are inflamed then calcium hydroxide won't work
• Mineral trioxide aggregate:

  • Used a lot in endodontics now
  • Silicates, aluminates, calcium sulphate, bismuth oxide
  • Stimulates cytokine release from pulpal fibroblasts stimulating hard tissue formation
  • Expensive but can be stored in Eppendorf tubes
  • Promising early results
  • Small numbers and short review periods
  • Physical suitability in load-bearing areas? - questionable because cement takes a long time to set (wouldn't be stable for a while)
  • Useful pulp cap after traumatic exposures
• Recommendations:

  • Choose teeth wisely
  • Well-placed restorations, monitor for signs of poor seal
  • Radiographic monitoring
• Desensitising pulp therapy = remove caries - apply Ledermix to the pulp exposure - anchor the Ledermix with setting dical then restore the tooth temporarily. In the second visit, move to ferric sulphate pulpotomy.

  
• Non-vital pulp therapy:

  • Used when pulp is necrotic (no blood)
  • Used when bleeding is difficult to stop (irreversible pulpitis)
  • This is where we will really miss formocresol
  • Two-stage pulpectomy has a dressing in between the two appointments

  
• Stay 2mm away because tooth germ will be underneath - don't want to harm it.

  
• • Don't shape; difficult - odd shapes
  • Don't use hypochlorite; can get through apex and damage tooth germ

  
• For RCT in primary teeth, obturate using resorbable paste and achieve a coronal seal with a PFMC.