minimal intervention dentistry - stabilisation of caries and ART

what did G.V.Black show that can arrest carious process

plaque control alone can arrest carious process

describe arrested caries

dark

hard

non-progressive

how can root caries in dentine be arrested

plaque control and the use of fluoride can arrest the process

++ve cavitated lesion = open to the oral environment so can use fluoride on it

how was caries historically removed

remove all infected dentine

often remove all stained dentine too

if necessary = expose pulp and carry out RCT

what is the pulpal response to caries

micro-organisms in plaque affect dentine and pulp (dentine has a physiological defence mechanism)

minerals plug tubules as they sclerose

this creates a translucent zone

where does secondary dentine formation occur

at pulpal side

where does tertiary dentine occur

where rapid caries activity occurs

when does pulpal inflammation occur

occurs early on in the caries process

pulp response can be detected by the white spot lesion in enamel

deep caries relates to chronic inflammation of the pulp

what does deep caries associate with

creation of tertiary dentine wh

what is tertiary dentine

contains irregular tubules which do not connect to those of original dentine

hence its less permeable

when does pulp death occur

when the bacteria invades the pulp itself

what is the pulp response during cavity preparations

new dentinal tubules are opened up by the cutting instruments (removal of smear layer)

they dont have sclerotic areas to protect them

pulp may then may be affected by heat and chemical

pulpal damage leads to signifcant damage and bacterial invasions = the pulp may be able to withstand

what does the stepwise caries removal technique show

shows that sealing carious dentine without any cavity preparations at all results in non-progression of the lesions

restorations can last 10 years in this state

how does the stepwise caries removal technique work

takes advantage of the reparative capabilities of the pulp

leave some soft demineralised dentine over pulp (soft dentine left over pulp = prevents exposing it)

peripheral caries still removed (this allows tight seal between tooth and restoration)

place GIC over pulp and restore cavity with GIC

definitive restoration placed at either time or 2/3 years later (GIC can chip or break hence definitive restoration needed ++ dont place GIC on molars)

why is GIC used as a seal in the stepwise caries removal technique

GIC is adhesive so forms a good seal to cavity

define soft dentine

deforms when a sharp probe is pressed into it

can be removed by hand excavator with little force

(infected dentine )

define leathery dentine

doesnt deform when a sharp probe is pressed into it

can still be removed with little force

has a latent ‘tackiness’

(affected dentine)

define firm dentine

physically resistant to hand excavation

needs pressure with excavator to remove it

define hard dentine

only sharp cutting edge or a bur can lift it

scratchy sound when probe is run over it

(sound dentine)

how does GIC help stop the progression of caries into the pulp

GIC eliminates air and carbohydrates leaking into the cavity

bacteria are therefore inactive

lactobacilli die and the number of streptococcus bacteria reduce (the rest of the organisms do not cause caries)

GIC also leaches fluoride and calcium ions to help with mineralisation

remove infected dentine

leave affected dentine

what was the previous stepwise technique (no longer done)

soft dentine over pulp is left (prevent exposing pulp)

CaOH placed over pulp to kill bacteria

dress tooth with GIC

dressing left for 6 weeks to 6 months

lesion reassessed (cavity preparation completed)

restored with permanent material

not all stained dentine is removed as it can still remineralise under final restoration

what was the role of CaOH

stimulates secondary and tertiary dentine

is bacteriocidal

in simple words explain how the stepwise cavity preparation is done

exposure avoided

pulp is left to remain itself

cariogenic bacteria render inactive

tooth encouraged to remineralise

what is ART

atraumatic restorative technique

when is ART used

used in underdeveloped countries

use din children or very nervous adults to stabilise caries

used to ‘buy time’ to prevent the progression of caries and symptoms

what does ART do

hand instruments remove superficial infected dentine

affected dentine left over pulp

GIC placed

doesnt replace tooth form, aesthetics and function

what does ART aim to do

preventative measures are introduced sot he patient is acclimatised to dental treatment (e.g. prophy)

intention is to stabilise things in short term while co-operation of the patient is achieved through acclimatisation

dressing the tooth moves biofilm to the surface and hopefully arrests the caries

teeth can then be reassessed later

what 2 components does ART consist of

a preventative ART sealant

a restorative ART restoration

what is ART sealant

high viscosity GIC (HVGIC) is placed over pits and fissures prone to caries using finger technique

excess removed by hand with excavator

what is ART restoration

removal of soft dentine with hand instruments and placement of high viscosity GIC