of

Objectives

Students should be able toExplain concept of pit fissure sealant and Preventive resin restoration (PRR)Discuss advantages, disadvantages and indications for pit and fissure sealantDiscuss advantages, disadvantages and indications for Preventive resin restorationDescribe the procedures of Pit and fissure sealant and Preventive resin restoration

Cariology

Dental caries is an infectious microbiological disease of teeth that results in localized dissolution and destruction of the calcified tissues.

S. Mutans have been demonstrated to have significant potential to cause caries

Host

Microflora Substrate

caries

Pit & fissure: highest prevalence of all dental caries

- narrow opening, almost impossible to clean

- Plaque accumulation (bacteria harbor)

- Fluoride is less effective to prevent pit & fissure caries

Pit & fissure: highest prevalence of all dental caries

- narrow opening, almost impossible to clean

- Plaque accumulation (bacteria harbor)

- Fluoride is less effective to prevent pit & fissure caries

Management of deep fissure

Prophylactic odontomy

Fissure eradication

Enameloplasty

Fluoride

Sealant

Management of deep fissure

Prophylactic odontomy (Hyatt 1923) Eliminating all susceptible fissures by cutting

a shallow, minimal width class I cavity in enamel. Then the cavity is filled with amalgam

Destructive, committed to

a restoration

Management of deep fissure

Fissure eradication (Bodecker 1929) Fissures reshaped by reducing the steep

cuspal inclines so that the occlusal surface is more readily cleansed by the patient

Destructive

Management of deep fissure

Enameloplasty Grinding away enamel on developmental

deep pit and fissure to create a smooth, saucer-shaped surface which is self cleansing or easily cleaned

Management of deep fissure

Fluoride Systemic/topical F¯ most effective in

preventing smooth surface caries but least effective in occlusal surface

It is speculated that neither stannous nor acidulated fluoride is able to impregnate the enamel at the depths of the fissures

Pit and fissure sealant

Management of deep fissure

Pit fissure sealing The idea is to form a barrier that protects pits

and fissures against bacteria and fermentable foods like sugars and starches, and thereby helps to prevent decay from starting deep within these fissures

Pit & fissure sealants were first introduced in 1967 by Cueto & BuonocoreEnamel is etched and bonded with resinFissure is sealed and protected from the ingress of plaque, microflora, and oral fluid.

Bacteria remaining in sealed fissures?

Studies have shown a decrease in numbers of microorganisms in lesions under intact sealants, and caries progression appeared negligible

Jenson & Handelman 1980, Handelman & Leverett 1985, Martz-Hfairhurst et al 1986

Advantages & Disadvantages

Caries is prevented as long as fissures remain completely sealed

If there is lost or leakage of the sealants, the tooth is once again at risk to caries

Needs periodic evaluation

Indications

Newly erupted posterior teeth with complicated fissuresHigh caries risk patient with deep pits & fissuresIncipient caries where caries is limited to enamelBite wing radiographs should be taken to ensure that caries does not extend to the DEJ and proximal surfaces

Contraindications

When adequate isolation cannot be achieved

Where definite occlusal decay is present

When proximal decay is present

On hypoplastic teeth

In uncooperative patients

Ideal Properties of fissure sealant

Should seal the pits and fissures against every penetration by oral flora

Adhere to enamel (high retention rate)

Should have a cariostatic action (F release)

Resistant to oral fluid and diet (acid, alcohol, etc)

Low viscosity

Ideal Properties of fissure sealant

Adequate mechanical properties on setting (strength, abrasive resistance)

Simple to use

Non toxic

Should be detectable

Have short setting/polymerization time

Materials of choice

Resin-based fissure sealantsUnfilled resin (bis-GMA)Lightly filled resinFluoride containing resin

Compomer

Glass ionomer cements

Resin-based sealants

Resin sealant : BIS-GMA PolyurethanesCyanoacrylate

Diluents (TEGDMA)

Choice of materials (resin-based sealant)

Light cured or Chemical curedChemical cured is no longer available

Unfilled or slightly filled resin filler particles are added to improve

abrasive resistance

Choice of materials (resin-based sealant)

Translucent or opaque (or coloured)

Compomer sealant

Composition Polymerisable Strontium-

alumino-fluoro-silicate glass Modified carboxylic acid Phosphate-modified

monomers

No laboratory or clinical date available

Glass ionomer sealant

Powder-liquid form

Chemical cured

Finer filler particles

Effectiveness

Retention rate & caries reductionResearches showed that sealant efficacy is

directly related to sealant retentionSealant placement also leads to a reduced

prevalence of restorations having to be placed later on.

Dennison & others JADA 2000 A retrospective study of 5,203 children

Graph shows Incidence of restoration placement on 1st molars with and without sealants.

0

2

4

6

8

10

12

14

16

treatment 3 4 5 years

Res

tora

tion

Inci

denc

e (%

)

No sealant

Sealant

6.5%

6.6%6.2%

Dennison & others JADA 2000 A retrospective study of 5,203 children

Graph shows Incidence of restoration placement on 2st molars with and without sealants.

0

5

10

15

20

25

treatment 3 4 5 years

No sealant

Sealant

10.4%

10.1%8.7%

Res

tora

tion

Inc

iden

ce

(%)

Effectiveness

Going et al 1977 reported caries prevention effectiveness (10 years) premolar: 84% molar : 30%

Mertz-Fairhurst et al 1984 (7 years) caries reduction effectiveness 55%

Romcke et al 1990 (10 years) 3% of the sealant had been replaced with restorations due to decay

Wendt &others 2001 reported 65% complete retention of sealant on 1st molar after 20 years with 13% of

caries/restorations placed 65% complete retention on 2nd molar with 5% caries/restorations placed

Effectiveness of GIC sealant

Retention rate & effectiveness comparable to resin sealant?

Armamentarium

Rubber dam armamentarium

Mouth mirror, straight probe, cotton forceps

Miller’s forceps

Prophy brush

Slow speed ¼ round bur

Procedures

Give a local anesthetic if necessary

Isolate the tooth

Remove calculus or debris

Procedures

If enamel caries is present, use ¼ round bur to widen the fissure and remove caries

Clean the pit and fissure surfaces with prophy brush and pumice

Procedures

Etch the surface with acid etchant

Wash and dry

Procedures

Apply sealant

Light cure

Procedures

Check occlusion

Procedures

Adjust occlusion using white stone or finishing bur

Sealant failure

Usually occurs at enamel-resin interface

Mostly caused by saliva or moisture contamination during application

Preventive Resin Restoration

Treatment of small carious lesions where caries is removed and restored with composite resin.Fissure sealant is then applied to the surrounding pits and fissures

Preventive Resin Restoration

Introduced by Simonsen and Stallard in 1977

Minimally invasive

G.V. Black “extension for prevention” is no longer practised

Small carious lesions within pits and fissures were removed and restored with composite resin while the remaining healthy fissures were sealed with a pit and fissure sealant

Advantages

Conservative approach

Minimum intervention -conserve more tooth structure

More aesthetic compared to amalgam

Disadvantages

Needs absolute moisture control

Bonding procedures are very technique sensitive

More time consuming

Failure to proper bonding will lead to leakage and recurrent caries

Indications

Small occlusal caries with a deep pit and fissure

An opaque, chalky or brown/black lesions along the pits and fissure, suggestive of caries

Type I

Caries is very minimal and limited in enamel

Remove caries with 1/4 round bur

Sealant is then applied

Pit & fissure Sealant

Type IIAfter caries removal with ¼ or ½ round bur, the preparation is limited in enamel but is greater than 1 mm in cross section

Posterior composite placement in the preparation

Sealant applied over composite restoration and fissures

Type III

Caries extends into dentin

Remove caries with suitable size round bur

Glass ionomer base placed over dentin. CaOH2 may be required if the cavity is deep

Restore the cavity with Posterior composite resin

Seal the entire surface with sealant

Small carious lesionQuestionable caries

Caries limited in enamel < 1mm in width

Caries limited in enamel> 1mm in width

Caries extend into dentin

Remove caries Remove caries Remove caries

Sealant CR placementCR placement, KIV lining

if deep

Sealant Sealant

Clinical Procedures

Local anesthetic if necessary

Apply rubber dam

Clean the tooth

Cavity preparationUse a small round bur

to widen the fissure

Clinical Procedures If caries is limited in enamel sealant If caries extend to dentin, use a pear-

shape bur (No 330) to gain accessRemove caries using suitable round bur

with slow speed hand piece

Clinical Procedures

Place liner or base in deep cavity (GIC)

Etch the cavity and the rest of occlusal surface

Clinical Procedures

Wash and dry

BondingApply primer and

adhesive over the cavity (follow manufacturer’s instruction)

Clinical Procedures

Composite resin placement

Underfill the cavityLight cure

Clinical Procedures

Seal the entire surface

Check occlusion

Recall

Maintenance and periodic review is essential

Replacement of sealant should be done if marginal debonding or sealant loss is observed