Pulp Therapy of Immature Permanent Teeth

What are the stages of root development according to the moorrees classification of root development

¼

½

¾

full development of the root with wide apex opening

full development with ½ closed apex

full development with closed apex

below stage 6 is immature

Immature vs mature teeth roots

Immature:

• Shorter roots (tooth cannot withstand a lot of force, stage 1 and 2 may not be suitable for any pulp therapy)

• Wide open apex (allows more blood to enter roots - better healing, also nothing stopping extrusion of material)

• Thin dentine walls (affects the prognosis of tooth, trauma may fracture the tooth in the future when treating immature teeth)

Mature:

• Closed apex

• Long root

• Thin dentine walls 

prognosis of pulp healing and why?

obturation ease

crown root ratio

strength of root

immature vs mature teeth?

Immature:

• Better prognosis of pulp healing - good blood supply (wider apex)

• less favourable crown root ratio

• difficult to obturate

• week root - increase fracture risk

Mature:

• not as good prognosis of pulp healing - less bloody supply

• better crown root ratio

• easier to obturate

• stronger root

What are aims of pulp therapy in immature permanent teeth? (4)

1. Preserve the vitality of the pulp or part of the pulp (to let the root continue growing - thicker walls, narrower canals)

2. Continuation of root development and root apex formation - (Apixogenesis - do pulp therapy so tooth can continue growing - apex close)

3. Induce of a natural apical barrier - (Apexification - we fix it)

4. Placement of an artificial barrier at the root apex 

Apexogenesis is for which type of teeth, vital or non vital?

Vital teeth, so apexification the tooth can no longer grow to maturity as the pulp is dead 

What are 4 procedures that fall under Apexogensis for vital teeth?

• Indirect pulp capping

• Direct pulp capping (not primary teeth anymore, can put CaOH no longer any resorption)

• Cvek pulpotomy (remove 2-3 mm of the pulp if there is any infammation)

• Conventional pulpotomy (removing whole coronal pulp)

these keep the vitality of the teeth so that the root development process can continue to maturity 

these procedures rely on good bloody supply from the apex

What are 2 pulp procedures for non-vital teeth in apexification?

• Inducing a calcified barrier at the apex:

• 1. Natural barrier with CaOH dressing (irritate bone on top of apex and body will lay down cementum like tissue to close apex artificially - body makes the barrier)

• 2. Artificial apical barrier with MTA cement - (we put the barrier)

• Pulp revascularisation (regenerate the pulp)

Definition of Apexogenesis? again what 4 procedures does this include?

Vital pulp therapy procedure performed to encourage physiological development and formation of the root end 

• indirect and direct pulp capping, partial pulpotomy (cvek), conven pulpotomy

Rationale for vital pulp therapy - Apexogenesis? (3)

• Continuation of root development needs an normal healthy pulp

• Pulp of immature teeth has a better repair potential (blood supply) 

• poor long term prognosis of endodontically treated immatuer teeth (most will fracture - you want thicker walls, closed apex )

What is a Cvek pulpotomy/partial pulpotomy?

• A procedure in which the inflamed pulp tissue beneath an exposure is removed to a depth of 1-3mm or more to reach the deeper healthier tissue

What is the rationale behind a cvek pulpotomy (2)?

• Based on the observations from Mjor and Townstad - dental pulp is usually inflamed only to a depth of 2 mm

• removing the infected part of the pulp and leaving the healthy part will stop the spread of the inflammation and encourage physiological development and formation of the tooth 

What procedure does this child require?

Partial pulpotomy

What materials can be used here for partial pulpotomy? (4)

• Non setting CaOH (opposite to primary teeth where it causes resorption)

• MTA (stronger bridge, easire to handle, seal - discolouration - tooth goes grey not ant and expensive)

• Biodentine

• whiet MTA - still causes discolouration

What is the procedure of a Cvek pulpotomy in immature teeth?

• if the bleeding doesn’t stop then you need to go deeper , then complete pulpotomy

• setting is hydrophobic, non-setting is hydrophilic and so stays on the pulp 

Success rates of cvek pulpotomy?

management of traumatic injury due to procedural error:

what do you do if there is saliva contamination (1)

when there is no saliva contamination (4)

• proceed for partial pulpotomy if saliva contamination

• if no saliva contamination:

• Direct pulp capping with CaOH/MTA/Bio-dentine:

• 1. irrigation

• 2. stop bleeding (if bleeding does not stop then proceed for partial pulpotomy)

• 3. Place non setting Caoh/MTA/biodentine

• 4. Seal with GIC and restore

Remember no MTA in anterioir teeth

What is apexification?

A method of inducing a calcified barrier at the apex of a non-vital tooth with incomplete root formation by the use of CaOH as a canal medicament

you change the CaOH every few months

What is the rationale behind apexification (2)

• Wide funnel shaped canals make endodontic treatment in immature teeth difficult

• An apical barrier is needed against which a root canal material can be packed 

Why is CaOH used in apexification? (2)

• high pH - bactericidal

• zone of liquefaction and coagulation necrosis - cementum like structure formed acting like a calcific barrier

Disadvantages to using CaOH? (2)

• Concerns about long application of CaOH may result in weakening the dentine walls and increase the risk of root fracture

• it is a long procedure that requires patients compliance and high cost 

2 indications and contraindications in apexification?

• Immature tooth and non vital - indications

• vital tooth, very short roots

What is the procedure for apexification?

chlorhexidine - material of choice for children

What are these series of radiographs showing?

the calcific barrier forming overtime and then oburation

What is this image showing?

different forms of hard tissue barriers

histologically all were cementum like

can be a ball on top, tin wall, rough

When is MTA used?

some adv?

long to wait 2 years

5 mm of MTA then the root filling material

What is regenerative endodontic technique?

(non vital tooth - want the root to grow more as its short or walls too thin for better prognosis so you regenerate pulp inside canal to continue tooth growing)

• Treatment procedure designed to replace damaged pulp tissue with viable tissue which restores the normal function of the pulp-dentin structure

• after regenerative endodontic treatment, continued root development and hard tissue deposition on the dentinal wall can occur under ideal circumstances

What are indications for regenerative pulp procedure? (4)

• Tooth with necrotic pulp and immature apex

• Pulp space not needed for post/core final restoration

• compliant patient/parent

• patient not allergic to medicaments and antibiotics necessary to complete procedure

Generally what happens in the first and second visit?

First visit:

• Disinfection of the canal using non setting CaOH or tri antibiotic paste (TAP) (ciprofloxacin, metronidazole, minocycline (part of the tetrac)) or double antibiotic paste (DAP) (ciprofloxacin/metronidazole)

second visit:

• create intra-canal bleeding to form scaffolding for the pulp repair/regeneration 

What happens in the first appointment in more detail?

What happens in the second appointment in more detail?

image for better visualisation: