W3 - Sealants and PRR - Mani Flashcards
How are fissures formed?
Calcification commences at the tips of the cusps and as they grow, they will fuse at the completion of the occlusal surface of the crown
However, fusion is not always complete
What are the 5 types of fissures
Plus inverted Y
Why are fissures at higher risk of decay? (3)
- Undetected demin
- Complex anatomy for plaque retention
- Tooth brush cannot reach
What radiograph is essential for early detection of fissure decay?
Bitewings
Describe the sealant effectiveness
Caries rate:
FS = 30%
No FS = 80%
- FS can also arrest progression of early non-cavitated lesions
- Carious lesions that are effectively sealed do not progress
PRR vs fissure seal
PRR is indicated if dentine is clearly involved
Areas that may require FS (6)
- Occlusal Fissures in molars (most common)
- Buccal pits of lower molars
- Palatal grooves of upper molars
- Palatal pits of upper anteriors
- Poor margins of restorations
- Erosion/attrition lesions
Pros and cons of resin as a sealant material
Pros
- Durable
- Stronger
Cons
- Stronger biofilm accumulation
- Polymerisation shrinkage = microleakage
- More technique sensitive
Pros and cons of GIC as a sealant material
Pros
- Fluoride release
- Chemical bond
Cons
- Weak to occlusal forces
- Shorter-lasting
Indications of sealants (4)
- Presence of deep pits and fissures on teeth
- Suspected/initial occlusal caries
- Children susceptible to Occlusal caries
- Children from non-Fluoridated areas with increased caries experience
Contraindications of sealants (4)
- Shallow pits/fissures
- Well-established caries - cavitations
- Teeth with proximal caries
- Teeth which are not completely erupted (depends on clinical scenario)
Steps of resin sealant placement
- Rubber dam / moisture control
- Clean the enamel (fissurotomy if necessary) + etch + bond
- Flow on sealant → Cure
- Check for overhangs, ditches
- Check occlusion
Steps of GIC sealant placement (5)
- Clean tooth
- Condition (10-20% polyacrylic acid for 10 seconds)
- Isolate (cotton rolls)
- GIC flow into fissure
- Protect (Fuji Coat)
Why may CR sealant fail?
Partial lifting of sealant (defective seal)
GIC controversies
GIC sealants are lost more often than resin sealants
- However, small amounts of GIC remain
- Caries are observed less frequently after GICs than resin sealants
- Appears that complete GIC retention not necessary
What is fluoride recharge?
Topical application of fluoride to GIC can be absorbed by resto, “recharging” the reservoir
What is amorphous enamel?
What problem does it cause?
How do we overcome problem?
Amorphous enamel = Enamel surface within fissure
- Enamel rods lay more parallel to the surface rather than at right angles
- Usually enamel rods are perpendicular to surface, allowing etch to create micromechanical adhesion
- Amorphous enamel causes bonding issues (no micro-mechanical adhesion)
- Fissurotomies are done to remove problematic amorphous enamel
If part of fissure sealant is lost or damage, does it need to be completely replaced?
No, just touch up the area to improve seal
Best approach for PRR
Sandwich technique
Fill cavity with GIC, place resin above restoration to seal remaining fissure
What is a pit?
Depressions located at the junctions or terminals of developmental grooves
What is a fissure?
Deep, narrow crevice formed at the depth of developmental grooves during tooth development
Definition of Fissure Sealant
The introduction of a seal onto the occlusal, buccal and palatal P+F to create a physical barrier to block biofilm nutrition and prevent bacteria proliferation
What can be used to clean the enamel prior to seal (2)
Brush/pumice
Minimal fissurotomy
