fissure sealant sajed mohammadian

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Definition

• According to ADA:An adhesive material that is applied to pits and fissures of teeth in order to isolate fromrest of the oral cavity

• According to simonsen:Material that is introduced into the pits and fissures of caries susceptible teeth, thus forming micromechanically bonded protective layer cutting access of caries producing bacteria from their source of nutrients.

HistoryThe first materials used

experimentally as sealants

were based on cyanoacrylates

but were not marketed.

By 1965 Bowen et al had developed

the bis-GMA resin,

which is the chemical reaction

product of bisphenol A

and glycidyl methacrylate. This is the

base resin to most of the current

commercial sealants. Urethane

dimethacrylate and other

dimethacrylates are alternative

resins used in sealant materials.

Properties

Some sealants contain filler, usually silicon dioxide microfill or even quartz

Sealant materials may be transparent or opaque.

The cariostatic properties of sealants are attributed to the physical obstruction of the pits and grooves

Activating or CuringSelf-cured(chemically)Light-cured(Ext energy sourrce):

uvVisible light-curing

Properties

Sealants are most effective in children when they are applied to the pits and fissures of permanent posterior teeth immediately on eruption of the clinical crowns(Art & Science 2013)

Sealant materials(self-cured and light cured) are based on urethane dimethacrylate or BIS-GMA resins. Tints frequently are added to sealants to produce color contrast for visual assessment.

• Using Glass Ionomer As Sealant:1. deeply fissured primary molars that are difficult to isolate

due to the child's precooperative behavior

2. in partially erupted permanent molars that the clinician believes are at risk for developing decay

• In such cases, glass ionomer materials must be considered a provisional sealant to be reevaluated and probably replaced with resin-based sealants when better isolation is possible

RATIONALE FOR USEOF SEALANTS

• 1. Bonded resin sealants, placed by appropriately trained dental personnel, are safe, effective, and underused in preventing pit and fissure caries on at-risk surfaces. Effectiveness is increased with good technique and appropriate follow up and resealing as necessary.

• 2. Sealant benefit is increased by placement on surfaces judged to be at high risk or surfaces that already exhibit incipient carious lesions. Placing sealant over minimal-enamel caries has been shown to be effective at inhibiting lesion progression. Appropriate follow-up care is recommended, as with all dental treatment.

• 3. Presently, the best evaluation of risk is made by an experienced clinician using indicators of tooth morphology, clinical diagnostics, past caries history, past fluoride history, and present oral hygiene.

• 4. Caries risk, and therefore potential sealant benefit, may exist in any tooth with a pit or fissure, at any age, including primary teeth of children and permanent teeth of children and adults.

• 5. Sealant placement methods should include careful cleaning of the pits and fissures without removal of any appreciable enamel. Some circumstances may indicate use of a minimal-enameloplasty technique.

• 6. Placement of a low-viscosity, hydrophilic materialbondinglayer as part of or under the actual sealant has been shown to enhance the long-term retention and effectiveness.

• 7. Glass ionomer materials have been shown to be ineffective as pit and fissure sealants but can be used as transitional sealants.

• 8. The profession must be alert to new preventive methods effective against pit and fissure caries. These may include changes in dental materials or technology.

Indications for Sealants

• Sealants may be indicated for either preventive or therapeutic uses, depending on the patient’s caries risk, tooth morphology, or presence of incipient enamel caries.(art & science)

• The sealant restoration is indicated primarily on the occlusal surfaces of permanent molars and premolars and may also be indicated for primary molars. (www.nature.com)

• Only caries-free pits and fissures or incipient lesions in enamel not extending to the dentinoenamel junction (DEJ) currently are recommended for treatment with pit-and-fissure sealants. (art & science)

•A history of dental caries•Deep retentive pits and fissures•Early signs of dental caries•Poor plaque control•Enamel defects, such as enamel hypoplasia•Orthodontics appliances

Contraindications

• Active caries lesion

• Interproximal caries

• Chalky view,soft,changing color to brown-gray

• Dentin caries

• And much caries….

SEALANT TECHNIQUE

After selection, the tooth is washed and dried and the deep pits and fissures are reevaluated .Ifcaries is present, restoration or a combination of restoration and sealing may be indicated

STEPS: (McDonald) (Pinkham)– CLEANING ISOLATION

– ISOLATION CLEANING

– ETCHING ,……

– WASHING

ISOLATION

• RUBBER DAM(McDonald: it’s better)96%

• Cotton rolls: 91%

• Absorbent shields

• SUCTION

CLEANING• Pamis past

– Rubber cap or brush mounted on angle

– Teeth brush

Or polish with air pressure(NaHCo₃)

• Eching

• Quarter round bur

ECHING

• Create Microporosities in the enamel surface• Generally, 30% to 50% acid solutions or gels are now

recommended.(phosphoric acid)

• Placment by:– Slender brush

– Cotton pellet

– Small sponge

• If a solution is used, one should gently agitate and replenish it, making an effort to avoid rubbing and breaking the enamel rods

• If gel is used ( skipping )

– Gel better than solution (control)

• 2-3 mm cusp slope and whole pits & fissures exist in lingual and buccal

• Not infiltrate to proximal

Eching(time)

• 15 seconds for permanent

• 15-30 s for primary

– be resistant to etching and may require a longer etching time

• More time for flurosis teeth

• no increase in bond strength with 120-second etching on primary teeth compared with 15-, 30-, or 60-second etching times.24 Their in vitro study showed that the etch depth increased between 60 and 120 seconds, but there was no corresponding increase in bond strengths.

WASHING

• Most of Most manufacturers' instructions advocate a thorough washing and drying of the etched tooth surface but do not specify a time interval. Phillips advocated a 40 second washing time.25 Norling has advocated 20 seconds

• The etched enamel is dried using a compressed air stream that is free of oil contaminants (frosty appearance)

Dentin Bonding Agent

• increased sealant retention in teeth even when salivary contamination occurred

• Use in Hard isolation:– Partially eraupted tooth

– precooperative behavior

• must be thoroughly air-dried across the surface to be sealed to avoid a thick layer of adhesive residue.

APPLICATION OF SEALANT

• Chemically Cured Sealant

• Visible Light Cured Sealant

Chemically Cured Sealant

• mixing without vigorous agitation can help to prevent the formation of air bubbles.

• catalyst to the base

• Short working time

Visible Light Cured Sealant• is not completed without the exposure of the material to the

curing light ( operating and ambient light )

• Long working time

• Placement Variety of putting sealant by different aplicator

• Method:– Putting

– Gently teased with a brush or probe into the pits and grooves

• curing just on surface area requires polymerization

• Porating Air bubble less than chemically type

• the unpolymerized surface layer should be removed by washing and drying the surface to avoid an unpleasant taste.

Blue Dental Curing Light

CHECK OF OCCLUSAL INTERFERENCES

• Articulating paper

• filled sealant => adjusting the occlusion before the patient is dismissed.

• Before removing rebberdam, the excess should be removed before detaching that:

– A small round bur

– Sharp instrument

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