Q1 final: smooth surface caries

Question 1

where are the locations for free smooth surface caries?

Answer 1

smooth enamel surfaces, spanning cej (starts at root surface usually), root caries

Question 2

where does smooth enamel surface FSSC occur

Answer 2

usually near gingival crest, lesions dont start in contact w gingiva but can sometimes spread there
- do not occur where normal function of tongue/lips/cheeks and other teeth move against the enamel surface! not self cleansing

Question 3

where does CEJ spanning FSSC start ?

Answer 3

begins on root surface usually, ,theres some gingival recession which is pathological or physio
-wraps circumferentially - teeth becomes difficult or impossible to treat reliably due to circumferential caries

Question 4

why does root caries occur usually

Answer 4

exposed root surfaces- elderly people have diminished saliva flow and caries occurs easily. can occur on any exposed root surface. can be circumferential!

Question 5

how is the apperance of a class V enamel lesion?

Answer 5

• diffuse demineralization (exposed margins fade out, un-erupted areas unafffected)
• usually well defined margin tracing the gum line and a diffuse extension in other directions from the central lesion.
• before cavitation can be remineralized w diet/homecare fluoride and mineral supplements but appearance doesnt return to normal. staining may intensify. dentin under remineralized e namel shell will not gain mineral but may be shielded from further decay

Question 6

what shape does caries spread within dentin once it reaches it?

Answer 6

mushroom shape, most aggressive along the CEJ. breakdown is accelerated by loss of solid dentin at the DEJ (undermines enamel)

Question 7

what is another term for stained dentin tubules between lesion and pulp

Answer 7

dead tracts; no longer contain live odontoblastic fibers. they are fluid filled and can transmit pressure variation to the pulp which is perceived as pain!!! (no live odontoblastic fibers doesnt mean insensitive at all)

Question 8

what are considerations for amalgam for class V caries rest

Answer 8

• amalgam (longevity but poor esthetics- not in esthetic zone. esthetic zones vary; typical smiles expose gumline of maxillary teeth as far back as first molar but few show mandibular teeth cervical to the height of contour
• achieving mechanical retention is tough
• easily placed on small flat surfaces. surfaces are often convex in both planes making all 90 degree exit angle diverge
• wrap aound preps very difficult to condense (grooves or points are usually required w retention features of some sort. condensing into wide convex preps is tricky.

Question 9

what are considerations for composite restorations for class V

Answer 9

• technique sensitive
• isolation may be difficult
• helps if margins are in enamel

Question 10

what are considerations for glass Ionomer /RMGI for class V restorations

Answer 10

• good caries resistance
• less technique sensitive than composite
• less wear resistant than composite
• fair esthetics
• fair polish

Question 11

what are options for class V restoration materials

Answer 11

amalgam, composite, glass Ionomer /RMGI and gold foil are all we talked about

Question 12

how do you perform a class V amalgam prep

Answer 12

using 245 or 330 high speed bur . outline form to edge of defective DEJ

• outline determined by searching for clean dentin at the DEJ.the stain can’t reach the DEJ unless dentin is demineralized so the color change is meaningful (will know whether dentin is impacted)
• once clean perimeter has been established, carious dentin can be removed with a slow speed round bur (#4) or a sharp spoon-excavator. using a high speed handpiece on soft dentin is inappropriate!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
• REMOVE soft dentin and LEAVE hard stained dentin!!!!!!!!! (it will be stained)

Question 13

what is activa- whats the purpose

Answer 13

a type of cavity liner (used at pacific) can be placed before condensing amalgam! layer to protect pulp. prep may leave open dentinal tubules and an inflamed pulp.
-but if it covers the entire axial dentin, amalgam may not be properly supported…

Question 14

on a class V caries amalgam prep, how are the walls facing with regards to eachother and how do you get retention

Answer 14

• convex surface of tooth yields divergent walls (occlusal and gingival walls of prep diverge)
• retention by placing grooves into the occlusal and gingival walls
• divergent retention grooves; use a 1/4 round bur along corner of both the occlusal and the gingival walls of the prep. running mesial distally. should be no pressure of bur against the axial wall!!!!!!!!!!! grooves end at the mesial and distal walls, although the rounded prep may leave this poorly defined.

Question 15

what are the dimensions of a class V amalgam prep that we did on tooth 18?

Answer 15

6 mm running mesiodistally, 1.5 mm occlusal-cervically

-convex axial wall

Question 16

what are the dimensions of the 18 class V prep we did

Answer 16

1 mm depth into axial wall, 6 mm mesiodistally, 1.5 mm occlusal/gingival size
-axial wall is convex, divergent occlusal/gingival and mesial/distal walls.