Operative One -- Selective Caries Removal and Cavity Preparation: Feitosa

Caries lesions initiates a cascade of re-treatment with increasing

loss of dental hard tissue

The death spiral

How to reduce the speed of the death spiral process

make minimal preparation.

- Do the prep as small as possible

What type of caries removal do we practice

Selective caries removal

Dental caries

the name of the disease

Carious lesion

is the consequence and manifestation of the disease- the signs or symptoms of the disease

Dental caries management

Involves control of the disease through prevention and noninvasive means at a patient level

Carious lesion management

Controls the disease symptoms at the tooth level

Clinical and radiographic classifications are by

severity and activity

Managing caries

Patient specific

Lesion specific

- Surgical

- Non-surgical

Based on Lesion Severity- Visual

Based on Radiographic Assessment

Before reaching for a handpiece the dentist must also

consider the non-invasive options

Guiding principles of carious tissue removal

To retain the tooth and the healthy/vitality of its pulp for as long as possible

Preservation of dental tissues- non demineralized and remineralizable

Avoidance of pulp exposure

Provision of sound cavity margins to achieve an adequate peripheral seal

Controlling the lesion and inactivating remaining bacteria

To retain the tooth and the healthy/vitality of its pulp for as long as possible

Reversible Pulpitis

Sensibility/Vitality - noraml responses to:

- Thermal tests

- Electric Pulp tests

Moderate and Extensive lesions

Maintaining Pulpal Health Vs Restoration Longevity

For moderate lesions (not reaching inner third of dentin) - the restoration longevity may be more important

Extensive- Deep lesions (radiographically involving inner pulpal third or quarter of dentin or with clinically assessed risk of pulpal exposure) preservation of pulpal health should be prioritized

When I do a selective caries removal can I leave caries (soft stained dentin) on the margin

NO

On the margin you need to have

the best bonding

centrally you can leave

some of the affected dentin

Dentin characteristics in caries tissue removal

Soft

Leathery

Firm

Hard

Soft Dentin

Will deform when a hard instrument is pressed onto it and can be easily scooped up (with a sharp hand excavator) with little force being required

Leathery Dentin

Although dentin does not deform when an instrument is pressed onto it LEATHERY dentin can still be easily lifted without much force being required

May be little difference between leathery and firm dentin, with leathery being a transition on the spectrum between soft and firm dentin

Firm Dentin

Physically resistant to hand excavation, and some pressure needs to be exerted through an instrument to lift it

Hard Dentin

A pushing force needs to be used with a hard instrument to engage the dentin, and only a sharp cutting edge or a bur will lift it. A scratchy sound or "cri dentinaire" can be heard when a straight probe is taken across the dentin

Periphery

Most external area of the preparation: in coronal areas is the enamel and DEJ, in gingival areas only dentin

The periphery must be

clean, hard and free of discoloration

Once restored the periphery is closest to the oral environment, so it is imperative to have a

good restoration seal in these areas

Caries removal steps: 1. Access

If lesion is NOT sufficiently cavitated, removal of enamel is necessary (High speed, with water)

Where there is enamel, extend the periphery depth and width to the depths of the 330 until the dentin at the DEJ is no longer

soft/stained.

(Halo of yellow/hard dentin exposed)

some caries lesion are accessible and initial enamel removal is

not necessary

Remove the remaining firm caries and demineralization along the DEJ with a small round bur using slow speed ______ [with/without] water?

Without

Ideally the dentin at the DEJ should be

hard and clean

The dentin along the DEJ should have a

light yellow appearance (halo) of approximately 1mm

Pictures

Caries removal instrument/ aids

Appropriate radiographs and current pulpal status

Clean dry tooth- avoid repeated or forceful drying to prevent pulpal damage

Adequate illumination and magnification

Spoon excavator, small and large round burs on slow speed

Mirror- most commonly missed areas are under cusp tips and at DEJ, always check with a mirror for these access-limited areas using multiple mirror angulations

For best visualization during caries removal

turn your handpiece water off

Intermittently spray water from the air/water syringe to keep the

dentin moist, this will help in preserving the pulp

Do not _____ the tooth, keep it moist

desiccate

Moist dentin allows for

visualization of the lesion

Margins should be

smooth and uniform

Remove undermined enamel

Final enamel presentation

prior to restoring the remaining enamel should be sound allowing for the most durable sealing of the restoration

Final enamel presentation: DEJ

Visibly free of stain and discoloration

Final enamel presentation: Enamel feels

hard with an explorer

Final enamel presentation: Enamel cannot be removed with

spoon excavator

Final enamel presentation: if enamel is little demineralized, it is

shiny and intact, Not flaky or dull

Selective removal is based on

Lesion severity

Lesion Severity

Moderate: caries limited to the outer 1.3 of dentin

Extensive: Caries extending beyond outer 1/3 of dentin

Moderate is selective to

FIRM dentin

Extensive is selective to

SOFT Dentin

Pulpally remove carious tissue until

leathery or firm dentin (resistant to spoon) is reached

- using a larger bur on slow speed or gently with a spoon

- Firm dentin on the pulpal floor, rather than aiming for hard dentin

The periphery of cavity

clean/hard (sound dentin)

Tissue removal to allow adequate

marginal sealing and bonding for a durable restoration

Centrally leaving affected dentin to

stay far from pulp

Extensive lesions: Selective caries removal steps

Evaluate the lesion- visually and radiographically

Access- remove enamel to obtain a clear DEJ. High speed with water

Caries removal at DEJ with smaller round bur, e.g #2 or #4 on Slow speed without water, so you can visualize what is being removed

If needed, remove soft wet disorganized carious tissue to leathery (experience required)