TOOTH CONS Flashcards

Question

Describe the curing reaction of CR

Answer 1

Initiation --> initiator becomes excited/activated by the light energy --> interaction and activation of monomers Propogation --> activated monomers bind to other monomers forming polymer chains Termination --> growing chains bind to other polymer chains --> complete polymerisation

Answer 2

C A. this is mostly correct but it never reaches 100% B. universal composites normally shrink 2-4% D. the greater the C-factor the greater the stress

Answer 3

C - the more filler content the more opaque the material

Answer 4

2mm | 4-5mm

Answer 5

C. - this is ideal as the lower layer is harder to reach with the light so a thinner increment will have increased potential for complete cure at that depth A. fibre-reinforced has excellent mechanical properties but the glass fibres cannot be polished so this would require a capping layer B. Flowable bulk fill MUST be covered with a sculptable bulk fill D. as above, a 4mm layer at the base increases the risk of inadequate curing

Answer 6

Liner - a fluid paste-type material used on pulpal/axial walls in 0.5-1mm increments to create a protective barrier between the dentine and restorative material Base - as above except >1mm increment beneath a final restoration

Answer 7

``` pulpal protection remineralise caries-affected dentine provide adequate cavity geometry for AR block undercuts chemical bond to dentine --> reduce microleakage restore lost dentine --> base stress relief during CR shrinkage resistance during AR condensation ```

Answer 8

True - GIC is prone to proximal defect if its in contact with the adjacent tooth

Answer 9

A B - eugenol-based materials adversely affect resin polymeristation C. no evidence to show flowable is better than other liners D. You want a therapeutic agent in any deep cavities where you may be near the pulp - a pulp exposure will require a directy pulp cap with calcium-silicate cements (MTA/Biodentine)

Answer 10

B A. Indirect restorations are more ideal and amalgam is the material of choice in direct, but CR is often selected due to aesthetics, efficiency and conservative properties C. complex CR's are a medium-term solution D. Highly-filled (>/=74%) universal CRs in 2mm increments are the composite resins that are recomended

Answer 11

Altered dentine --> from irrigant and dressing tx Reduced tooth structure --> significant removal in tx Reduced proprioception --> sensation removed = higher loads applied without the patient awareness Decreased moisture --> there is a small degree of dehydration 5-12% but this is not a key issue

Answer 12

C A - >50% B - must be all tooth structure D - core material should be amalgam or CR

Answer 13

1. Establish outline at optimal depth - direct simplest access to caries, removing peripheral caries in enamel, the DEJ and 0.5mm of dentine - freedom from contact - outline beyond fissure system 2. Satisfy retention, resistance and convenience form 3. Remove deeper caries - from periphery to deepest region - using large slow speed bur and tactile sensation 4. Complete the cavity - adjustments to cavity margins, removing weakened enamel, debridement 5. Place a liner or therapeutic IF needed 6. Matrix selection and placement 7. Bonding procedure - total etch (three step, two step) - self-etch (two step, one step) - selective etch (three step, two step) 8. Place restoration 9. Finish restoration

Answer 14

Probs the only q they will have for simple composite veneer. • Indications: o Inadequate tooth colour that does not respond to any whitening method o Unsatisfactory tooth shape and/or position o Inadequate tooth size o Diastemas o Partial tooth crown fracture o Gummy smile ``` • Contraindications: o Bruxism o Bad habits (e.g. nail biting) o Weak support  Teeth with big fillings  ETT without intraradiculat posts o Unrealistic expectations o Bad OH ```

Answer 15

1. Irregular alignment of teeth 2. Caries positioned towards labially (tooth tissue preservation) 3. Extensive caries involving labial surface 4. Old restoration placed labially 5. If you're the too-big-for-her-boots OHT at ashleigh's workplace

Answer 16

Palatal bevel indicated when outside of occlusal contact area and palatal chamfer indicated when in occlusal contact area.

Answer 17

 Filled: Filler particles only have a small impact on the outcome of the fissure sealant and reduces ability of the penetration into the fissure sealant. Filled fissure sealant generally require more occlusal adjustment.  Unfilled: Low viscosity allows better penetration into the fissure and lower microleakage rate. Occlusal adjustments generally not required.

Answer 18

A) Enamel - Macro tags = Resin penetrates adjacent enamel prisms - Micro tags = Resin penetrates individual HA crystals B) Dentine - Adhesive layer = Complete zone of demineralisation with only resin - Hybrid layer = Complete demineralisation of inorganic material but collagen remains - penetration of resin around these collagen fibrils - Resin tags = Penetration of resin into the dentine tubules

Answer 19

CaOH = Indirect pulp capping - Less expensive - More soluble - Stimulate tertiary dentine (dentine bridge) irregular, porous, cellular inclusions - Inferior marginal adaption CaSilicate = Direct pulp capping - More expensive - Less soluble - Stimulate tertiary dentine (dentine bridge) homogeneous, tubular, less cellular inclusions - Better marginal adaption - May discolour tooth (bismouth oxide)

Answer 20

Pulpal protection (isolation) Tertiary dentine formation Remineralisation of caries affected dentine Reduction of bacterial count