midterm 1 Flashcards
factors affecting gene expression
- time (development stage)
- environment (in body)
- type of cell
do most dental diseases follow mendelian inheritance
no
which dental diseases follow mendelian inheritance
- amelogenesis imperfecta
- dentinogenesis imperfecta
what general diseases (following mendelian) affect teeth
- cystic fibrosis
- ectodermal dysplasia
- down syndrome
issues with down syndrome pt
- caries
- malocclusion
- abnormally shaped teeth
- MAXILLARY HYPOPLASIA
multifactorial inheritance/ complex traits are due to
gene-environment interactions and changes in gene expression
multifactorial inheritance examples
- clept lip/palate
- dental caries
- perio
response to environmental factors and susceptibility to disease is due to
modifying gene expression
can only modify dental diseases by
modifying environmental factors
what two genes affect caries
GLUT2 and TAS1R2
GLUT2
thr/ile polymorphisms = higher caries
TAS1R2
ile/ile polymorphisms = higher caries
higher associations and less discrimination/noise
- environment
- oral microbiome
- salivary proteome
- genome
what 6 factors make up comprehensive caries risk assessment model
- SES
- OH and F-
- diet
- genomic markers
- microbiome markers
- proteomic/metabolomic markers
alveolar bone remodels during
- tooth eruption
- mastication
- ortho tooth movement
- jaw bone (pathology)
steps for RANK
- osteoblast makes RANKL
- RANKL binds to RANK on pre-osteoclasts
- diff into osteoclasts and resorption begins
inhibitor of RANKL
osteoprotegerin (OPG)
what secretes OPG
osteoblasts
osteoblasts are derived from what
lining cells on bone
what do osteoclasts make
howship lacuna (bone pit)
what enzyme is found on ruffled border
cathepsin k
steps for HAP dissolution
- osteoclast makes carbonic anhydrase II
- CAII releases H+
- H+ move out by ATP pump
- pH drops to 2.5-3.0
what two enzymes are important for degrading organic materix
-cathepsin K and MMP-9
what does cathepsin k make
collagenase to break down type I collagen
what does mmp-9 make
collagenase B
function of collagenase B from mmp-9
migration and GF
function of mmp-13
resorption and differentiation
steps to remove products of resorptive zone
- endocytosis
- membrane bound vesicle
- fuse with FUNCTIONAL SECRETORY DOMAIN (FSD)
- exocytosis
postmen women have low estrogen causing
high RANKL= more osteoclasts = more bone loss
what inhibits osteoclasts
bisphosphonate
people taking BISPH can have
osteonecrosis of the jaw bone during surgery (BRONJ)
RANKL knockout mice had
- osteopetrosis
- defects in tooth eruption
- low osteoclast #
mineralized tissues are
composite materials
human teeth are
composite of composite structures
forms of calcium carbonate
- acc
- valerite
- aragonite
- calcite
aragonite crystals forms a
“stack of coins” structure that make up gastropod nacre
hard connective tissues example
- dentine
- cementum
- bone
- not enamel (no collagen; has distinct enamel proteins)
what makes up hard CT
fibrous protein (eg. collagen) and proteoglycans, phosphoporteins, phospholipids
main mineral in teeth**
calcium phosphate dihyrate
structure of calcium phosphate dihydrate
rhombic prism
ca phosphate OH2 can form
-crystallites (hard tissue)
OR
-rods (enamel) (bigger)
3 surfaces of apatite crystallite
- hydration shell
- crystal interior
- crystal surface
* change occurs at all surfaces
dihydrate ions can be exchanged with
F- and Cl-
conversion of HAP to FAP
2OH- replace with 2F-
-longer and wider
advantage of FAP over HAP
FAP doesnt dissolve much in acid than HAP
two methods of achieving mineralization
- matrix vesicles
2. heterogenous nucleation
what mechanical model of equilibrium is Ca Phos
metastable
phase transition of ca phos
single ions, clusters, larger clusters, solid
supersaturated tissue fluid undergoes
spontaneous precipitation
homogenous nucleation or matrix vesicles
solids increase in size and rupture vesicles, solid deposits on matrix
heterogenous nucleation
- ca-proteo in gap of collagen fibrils
- 3P cleave them
- attract - particles so P come in
enamel composition
mineral 95
organic 1
water 4
developing enamel composition
mineral 15
organic 20
water 65
dentin composition
mineral 70
organic 20
water 10
bone composition
mineral 60
organic 20
water 20
cementum composition
mineral 50
organic 20
water 30
FAP is more/less thermodynamically stable than HAP
more
3 properties of FAP after F- substitution
- more compact
- less acid soluble
- easier to remineralize
inorganic oral care product
amorphous calcium phosphate
bioglass
-raises pH (trades H+ for Na+), allows precip, HAP over dentin
bioapetite
- less crystallinity
- many structures due to diff 1proteins
main type of collagen in bone
type I collagen
function of alkaline phosphatase
shuttles P from proteins to HAP and back
matrix vesicles deliver
proteins like osteopontin to mineralization foci
without the dentin proteins you get
too much predentin and not enough maturation
DSP/DPP protein is associated with
dentinogenesis imperfecta type 3
what non-collag protein is found in cementum
osteopontin
