Pit and Fissure Sealants
Why are fissures caries susceptible?
Toothbrush does not get into fissures
Sealant composition
Type of specialized plastic (resin) or glass ionomer material Matrix Filler
What are the elements of sealant kits?
- Acid etch - Cavity Indicators - Drying and/or bonding agent (optional) - Sealant material
What are the factors in selecting teeth for sealants?
- Age - Hygiene - Caries risk - Diet - Fluoride history - Tooth type - Morphology
Acid etch - Precautions
- Avoid contact with adjacent teeth or soft tissues by using mylar strips or matrix bands - Avoid contact with skin, eye and clothing - If ingested, take antacid
How is sealant applied to tooth?
- Bristle brush, Bur, Air abrasion, Laser, Sharp explorer to remove debris - Rinse - Position patient - Check occlusion (Avoid placing acid etch and sealant on marked areas from articulator paper) - Isolate tooth/teeth (treat quadrant separately - use rubber dam, cotton roll, etc.) - Dry tooth - Apply acid etch 15-20s (reetch 10s if saliva contamination) - Extend 1-2 mm beyond pit and fissures (avoid cusp tips) - Rinse (use high volume evacuator, rinse for 20s to avoid phosphate remaining) - Dry tooth (must give frosty chalky white appearance) - Apply PrimaDry (for 5s) - Gently blow dry - Apply bond agent - Apply sealant (pos. teeth 1st, pop bubbles with explorer) - Light cure - Check sealed teeth with explorer (tooth smooth but not soft) - Remove isolation materials (use wet cotton roll) - Check occlusion (correct with bur or floss) - Document what was used - Infection control
Types of curing for sealants
- Chemical cured - Visible-light cured
Requirements for adhesion
- Clean surface - Good wetting by adhesive - Good adaptation to substrate - Good interface - Good curing ICSWA
Sealant shades
- Clear - Tinted - Opaque
How can sealants fail?
- Debris and/or saliva contamination - Air inclusion during manipulation - Late manipulation of self-cured sealants - Most common in max. and man. 2nd molars
When should etch longer?
- Deciduous teeth - Saliva contamination - Air abrasion or prophy jet used - Highly mineralized teeth
Indications for sealants
- Deep fissures - Incomplete or ill formed pits - Newly erupted teeth - High caries rate - Children - Molars
Acid Etch
- H3PO4 (35-50%) - Dissolves organic portion of enamel - Micromechanical retention - To create more surface area for better adhesion
Common problems
- Improper etched surface (doesn't appear frosty and chalky white) - Dentin etching - Contamination - Non-adherence
Unfilled sealants
- Less resistant - Clear, making detection difficult - Best used when high spots can't be adjusted
Why sealant maintenance is needed?
- Loss of all or part of sealant - Staining at edges - Discolouration underneath sealant
Properties of Glass Ionomer
- More viscous - Less retention - More brittle - Less resistant to occlusal wear
Risks assoc. with sealants
- No carcinogens or toxic materials - Have xenoestrogens (but conc. too low) - Occlusal trauma - Danger from cure light
Chemical cured - Pros
- No cure light or risk of eye damage - Can apply sealants to several teeth
Properties of Clinpro™ Sealant
- Pink - Easy-to-see - Cures to natural white - Low viscosity - Fluoride-releasing sealant
Visible-light cured - Cons
- Potential eye damage - Additional cost - Cure time increased with # of teeth - Difficult for pos. teeth
Visible-light cured
- Pre-mixed Dimethacrylate + diluent + activator + light = sealant
How to repair sealants?
- Reapply if total loss - Repair partial loss (Roughen with diamond stone, re-etch 20s, reapply sealants)
Sealant material - storage and handling
- Refrigerate when not in use - Use PPE
Sealant types
- Resin sealants (Bis-GMA, Urethane-based resin) - Sealants with fluoride (Glass Ionomer) - Filled sealants - Unfilled sealants
Chemical cured - Cons
- Setting time - 2 mins - Voids from mixing material - Changes in viscosity over time
Visible-light cured - Pros
- Setting time - 20s - No mixing - Won't set - Does not get thick
Contraindications for sealants
- Shallow fissures - Well coalesced pits - Fluoride rich emanel - Low caries rate - Occlusal or proximal caries - Adults
PrimaDry - storage and handling
- Use PPE - Store at room temp. and out of sunlight
Acid etch - storage
- Use PPE - Store at room temperature
Sealant material - precautions
- Use precaution - Ingestion: induce vomiting
Acid Etch - examples
3M Innovation: Adper™ Prompt™ L-Pop™ Self-Etch Adhesive
What is a sealant?
A thin plastic coating placed in the pit and fissures of teeth to act as a physical barrier to decay.
Drying agent (PrimaDry)
Acid etching and Primadry (alcohol based) allows enamel to be easily "wetted" (by sealant)
Chemical cured
Base and catalyst Monomer & initiator + diluted monomer & 5% Organic amine accelerator
Sealant material - active ingredient
Bis-GMA
Curing unit times
Conventional cure light with halogen bulb = 20s Plasma arc or laser = 5-10s
Examples of indicator dye
DIAGNOdent
Filled sealants
Filler - fumed silica or silanated inorganic glasses More wear resistant
Can you seal over caries?
Just incipient caries
Which tooth is most likely to have pit and fissure caries?
Lower molars (50%) Upper molars (35-40%)
Which has more retention properties? Resin sealants or Glass Ionomer?
Resin sealants because it is less viscous and reaches fissures easily.