Biological considerations in restorative dentistry

Question 1

What are some consequences of Xerostomia?

Answer 1

1. increased risk of caries
2. difficulty w dentures
   - mucosal thinning
   - retention of F/F

Question 2

Why are Bisphophonates a contraindication for OD?

Answer 2

• interferes w healing
• can cause osteonecrosis of jaw, exposed bone that is very smelly and necrotic

Question 3

Bisphophonates are given in what kind of patients?

Answer 3

1. Cancer pxs under cancer tx
2. Osteoporosis pxs

Question 4

Gingival hyperplasia can be caused by what medications?

Answer 4

1. Phenytoin (anti-epileptic)
2. Nifedepine (calcium channel blocker for hypertension)
3. Cyclosporin (immunosuppressant, anti-rejection)

Question 5

Xerostomia is often a result of..

Answer 5

1. radiation therapy (cancer in head & neck)
2. autoimmune disease (sjogren’s disease)
3. drugs (antihypertensives, antihyperlipidemia, diuretics, antidepressants, sedatives)

Question 6

What condition are we most worried about in patient’s w heart diseases?

Answer 6

Infective Endocarditis

Question 7

Name some common drugs that pxs are allergic to..

Answer 7

1. Penicillin
2. Sulphur drugs
3. Articaine LA contraindicated

or
Restorative materials, e.g. Latex (contact dermatitis)

Question 8

Amalgam is a good material cuz

Answer 8

• strong and durable
• cost effective

Question 9

What is a concerning component of tooth coloured restorations?

Answer 9

BPA, Bisphenol A

• dental sealants & composite filling materials contain BPA derivatives
• accumulating evidence that BPA can pose health risks, endocrine-disrupting, estrogenic properties

but
- ESPA (european food safety authority) says BPA in dental tx poses no health risk to consumers of any age grp
- FDA also concluded that the level humans consume are safe

Question 10

how is blue light damaging?

Answer 10

blue light penetrates tissue, cellular damage, DNA of mitochondria in retina, macular degeneration

Question 11

how should you remove a dry cotton roll from the px’s mouth

Answer 11

wet the cotton roll b4 removing, a dry cotton roll can tear of mucosa

Question 12

what is biologic width?

Answer 12

epithelial attachment + connective tissue attachment. ard 2.04mm.

basically gingival sulcus to alveolar bone

Question 13

what is the significance of biologic width in clinics?

Answer 13

• when u go subg => violate biologic width
  e.g. making a crown, udw to violate biologic width and cause recession

Question 14

composites can be placed in increments of up to..

Answer 14

2mm

Question 15

overcutting risks..

Answer 15

1. reduces strength of remaining tooth
2. increases risk of pulpal damage

Question 16

damage to adjacent teeth occurs more frequently in..

Answer 16

1. distal > mesial (cuz obstruction of vision)
2. upper (61%) > lower (25%) (cuz indirect vision)

Question 17

how does dentine change w cavity depth? & how does this affect CR bond strength?

Answer 17

superficial dentine=> 1. narrower dentinal tubules + 2. large amt of intertubular dentine + 3. low water content

deeper dentine=> 1. wide dentinal tubules 2. small amount of ITD + 3. higher water content

so CR bond strength is lower in in deep dentine than superficial dentine by 30-50%

Question 18

how is bond strength altered in NCCLs?

Answer 18

• hyper mineralised outer layer w bacterial inclusions on a bed of denatured collagen fibrils
• under which is dentinal tubules

clinical implications:
- NCCL CR bond strength is 20-40% lower than sound dentine

Question 19

why are RM GICs not placed in areas of occlusion/contact?

Answer 19

cuz its weak, not strong enough

Question 20

what is the stomatognacthic system?

Answer 20

combination of all structures involved in speech & in receiving, mastication & deglutition of food as well as para-functional acts