Clinical skills* Flashcards
Indications for use of fissure sealants?
High caries risk (high sugar) Limited manual dexterity Medically compromised (chemo, immunity and bleeding disorders) Deep fissures Management of non-cavitated caries Apart of PRR Marginal restorations (previous) All newly erupted permanent teeth
Clinical proven - 89% reversal of carious to non carious
Fissure sealant application technique - evaluation, etching pattern?
Isolate tooth (dam or cotton wool)
Clean tooth (brush or probe)
Etch (30-50% phosphoric acid) for 20-30s
Wash for 10-20s and dry until frosted and matt
Sealant applied (no air bubbles)
Light cure 20-30s
Check adequacy and retention (smooth, occlusion, undercure and no extensions)
Provides micro mechanical form of retention (core removed)
Classifications of fissure sealants?
Polymerisation - self or light
Colour - translucent or opaque
Filler content - filled or unfilled
Polymerisation types?
Self is chemical cured, mixture of 2 chemicals, limited time (5yrs)
Light cured is by command (20yrs)
Importance of moisture control during fissure sealant application - solutions?
Main reason for failure
Etched enamel can become contaminated with saliva proteins compromising bond to the hydrophobic sealant
Rubber dam
Contraindications for fissure sealants?
Poor cooperation
Isolation issues
Caries present
Standard prevention for all children fissure sealants - indications? placement? maintenance?
Placed on all newly erupted teeth (resin-based)
Ensure buccal pit of lower first molars and palatal fissures of upper first molars
If uncoop apply glass ionomer fissure sealant and with fluoride varnish
Check sealant integry every recall visit (top up)
How are caries formed and arrested?
Driven by the biofilm on the surface of the enamel causing a lesion due to the production for acid, via the digestion of sugars
Arrested by removal of dental plaque from the lesion or lesion isolation from the biofilm allows arrest
Minimal intervention technique - newly found phenomenon allows?
Significant dentine-pulp complex repair is capable, which allows leaving small amount of affected dentine, as long as there is no bacteria present
ICDAS - 0-6? International caries detection and assessment system
0 - sound tooth (after air dry)
1 - visual change in enamel (white spot on pit/fissure after dry)
2 - distinct change seen when wey
3 - localised enamel breakdown (no dentine)
4 - underlying dark shadow
5 - distinct cavity with dentine
6 - extensive cavity with dentine
Examination of suspected caries?
Clean ooth Cotton wool if wet Remove saliva Examine wet Dry for 5s Visual inspection
Treatment options for occlusal caries?
Prevention: - dietary analysis, OHI, fluoride treatment and chlorhexidine Fissure sealants PRR Filling (conventional restoration)
Topical fluoride varnish - overview?
Tries to produce remineralisation
NaF, APF, SnF2
Home use toothpastes, mouth washes and gel
Stained fissure appearance and indications?
Discolouration not due to staining, developmental opacities or fluorosis
Found in pits and fissures (confined)
No evidence of shadow indicating dentinal caries
Radiographs if possible
Sticky fissure - diagnosis?
Never use a straight probe (cause damage or introduce bacteria)
Clean and dry under good lighting, examination with the support of BW radiographs
To seal or not to seal?
If in doubt = seal
No harm in sealing
Non-cavitated occlusal caries
Unethical to undertake invasive treatment when placement and maintenance of sealant is as effective
Occlusal caries - reason for high caries risk? difficult diagnosis? hidden caries? diagnosis? when to restore?
Stagnation points for plaque
Surface often looks intact
Occult - surface intact, but caries underneath, bacteria enter via deepest part of fissure and spread along ACJ
Diagnosis:
- radiographs (radiolucent show infected dentine)
- caries always underestimated radiographically
Obvious cavity and infected dentine
Preventive resin restoration (PRR) - technique? indications?
Outline access with pear shaped diamond high speed bur Removed all affected fissure Decalcified fissure left 2 lesions present, treat separately Try to leave oblique ridges if possible Remove caries until the ADJ (pulp protection) Etch for 15s Wash tooth Dry tooth (dentine moist) Primer to enamel and dentine Dry for 5s (shiny appearance) Adhesive to enamel and dentine Cure for 10s Build up restoration with resin composite Cure 30s Etch remaining fissures 30s Wash Dry Sealant Cure Check occlusion Used when fissure system becomes carious (localised)
Conventional restorations - indications? technique?
Cavity large enough to involve most of fissure system Occlusal registration Outline form Keep minimal but remove caries Build up base as necessary Etch, prime and bond Apply composite in increments and cure (avoid contacting both lateral walls) Cure (up to 2mm)
Definition of an approximal caries - how to diagnose? when to intervene? cavity preparation technique?
Found interproximally (CII) of the molar and premolar teeth
Diagnosis with visual inspection with drying and transillumination with the aid of radiographs
Intervention is only necessary if the caries has reached the amelodentinal junction, cavitated or visible on the radiograph
Due to the caries located proximally, entry is necessary via the occlusal dimension
Creating a cavity - requirements for a CII? occlusal caries also present?
Break through the contact point, into the embrasure area (minimal is best)
Must break contact point
Creation of a proximal box the same width as the contact point, remove the caries present and try to avoid entering the occlusal surface (parallel box walls, 1.5mm)
Ensure safety of the adjacent tooth with protection
Remove the occlusal caries by following the fissure pattern of the tooth, a reduced depth compared to the box, and combine the 2 cavities
Materials for cavity filling - material? cavity modification? function?
Composite - no mod (etch and bond), removes smear, demineral prisms and forms micromechanical retention for composite tags
Amalgam - needs nudercuts, grooves and a widen base to slot in (rounded line angles), stops displacement
GIC - no mod (chemical), polyacrylic acid removes smear and chem adhesion with Ca
Dental matrices - function? types? avoiding overhangs? how to place it?
Contain the cavity for the restoration
Adapts the material to form the cavity floor and walls, giving a good marginal seal without ledges
Re-establish the contact points with reducing retention factors
Circumferential or sectional
Wooden or plastic wedge to be inserted to ensure no deficiencies around the cervical portion of the matrix
Top of matric at marginal ridge height, bottom of the and fully covers the bottom of proximal box and tightly adapted, band should be tightened for desired shape
Basic structure and reaction of a resin composite?
Repeating structural units (monomer) linked together as a product of free radical polymerisation. As monomers cross link between adjacent monomers the mobile monomer moves closer and convert into covalent bonds incurring bulk contraction, causing composite to undergo volumetric contraction (shrinkage)
