Operative Dentistry I: E2 (Cariology) Questions and Answers
1. Define dental caries: infectious, bacterial disease caused by cariogenic plaque
formation on the tooth surface that results in localized dissolution and destruction
of calcified tissues leading to loss of tooth structure
- localized destruction of susceptible dental hard tissue by acidic by-products
from bacterial fermentation of dietary carbohydrates
- bacterial driven, generally chronic, site-specific, multifactorial, dynamic disease
process that results from the imbalance in the physiologic equilibrium between
the tooth mineral and plaque fluid;
pH drop = net mineral loss over time
2. pH drop =: net mineral loss over time
3. Causative factors for caries development: - host
- bacteria
- substrate
- time
4. Components of the host: tooth, saliva, muscular activity, habits, environment
5. inorganic % of enamel vs. dentin/cementum: 96%: enamel 70%
dentin/cementum
6. organic + water % of enamel vs. dentin/cementum: 1% organic, 3% water:
enamel
, Operative Dentistry I: E2 (Cariology) Questions and Answers
20% organic, 10% water: dentin/cementum
7. Enamel is microscopically porous which makes it : permeable
8. Basic unit of tooth enamel
- tightly packed, highly organized mass of hydroxyapatite crystals, which are
HEXAGONAL in shape and provide rigidity and strengthen enamel: enamel rod
9. What is enamel made of?: hydroxyapatite crystals
10.components of enamel: - enamel rods
- interrod enamel
- rod sheath
11.Located around the rod enamel, same composition as enamel rod, runs in different
direction: interrod enamel
12. where enamel rods meet interrod enamel, more ORGANIC content, reduces stress
on rods: rod sheath
13.rod sheath: where enamel rods meet interrod enamel, more organic content,
reduces stress on rods
14. Which type of apatite crystal is the most soluble in acid?: carbonated apatite
15.Which type of apatite crystal is least soluble in acid?: fluoro apatite
16.About % of the crystal is carbonated hydroxyapatite. It is more easily
dissolved by acids: 20%
, Operative Dentistry I: E2 (Cariology) Questions and Answers
17.Which is softer? Dentin or enamel?: Dentin; hydroxyapatite crystals are 30
times smaller in dentin
18.Dense mineralized tissue that surrounds the tubules of coronal tooth DENTIN.
- composed mainly of crystals of carbonated apatite together with a small amount
of collagen: peritubular dentin
19.lies between the tubules, less-calcified matrix that consists of some apatite crystals
embedded within a COLLAGEN MATRIX: Intertubular dentin
20.peritubular dentin vs. intertubular dentin: - Peritubular dentin: DENSE MIN-
ERALIZED tissue, surrounds tubules of coronal tooth dentin
- Intertubular dentin: lies between tubules, LESS CALCIFIED MATRIX, consists of
apatite crystals embedded within a collagen matrix
21.Why is dentin more susceptible to caries than enamel?: - less inorganic
content
- hydroxyapatite crystals are smaller
- more carbonated apatite
- greater numbers of impurities in crystals
- critical pH is higher than enamel
- tubules offer channels for diffusion of bacterial acids
22.The number and diameter of tubules increase from to the : DEJ -->
1. Define dental caries: infectious, bacterial disease caused by cariogenic plaque
formation on the tooth surface that results in localized dissolution and destruction
of calcified tissues leading to loss of tooth structure
- localized destruction of susceptible dental hard tissue by acidic by-products
from bacterial fermentation of dietary carbohydrates
- bacterial driven, generally chronic, site-specific, multifactorial, dynamic disease
process that results from the imbalance in the physiologic equilibrium between
the tooth mineral and plaque fluid;
pH drop = net mineral loss over time
2. pH drop =: net mineral loss over time
3. Causative factors for caries development: - host
- bacteria
- substrate
- time
4. Components of the host: tooth, saliva, muscular activity, habits, environment
5. inorganic % of enamel vs. dentin/cementum: 96%: enamel 70%
dentin/cementum
6. organic + water % of enamel vs. dentin/cementum: 1% organic, 3% water:
enamel
, Operative Dentistry I: E2 (Cariology) Questions and Answers
20% organic, 10% water: dentin/cementum
7. Enamel is microscopically porous which makes it : permeable
8. Basic unit of tooth enamel
- tightly packed, highly organized mass of hydroxyapatite crystals, which are
HEXAGONAL in shape and provide rigidity and strengthen enamel: enamel rod
9. What is enamel made of?: hydroxyapatite crystals
10.components of enamel: - enamel rods
- interrod enamel
- rod sheath
11.Located around the rod enamel, same composition as enamel rod, runs in different
direction: interrod enamel
12. where enamel rods meet interrod enamel, more ORGANIC content, reduces stress
on rods: rod sheath
13.rod sheath: where enamel rods meet interrod enamel, more organic content,
reduces stress on rods
14. Which type of apatite crystal is the most soluble in acid?: carbonated apatite
15.Which type of apatite crystal is least soluble in acid?: fluoro apatite
16.About % of the crystal is carbonated hydroxyapatite. It is more easily
dissolved by acids: 20%
, Operative Dentistry I: E2 (Cariology) Questions and Answers
17.Which is softer? Dentin or enamel?: Dentin; hydroxyapatite crystals are 30
times smaller in dentin
18.Dense mineralized tissue that surrounds the tubules of coronal tooth DENTIN.
- composed mainly of crystals of carbonated apatite together with a small amount
of collagen: peritubular dentin
19.lies between the tubules, less-calcified matrix that consists of some apatite crystals
embedded within a COLLAGEN MATRIX: Intertubular dentin
20.peritubular dentin vs. intertubular dentin: - Peritubular dentin: DENSE MIN-
ERALIZED tissue, surrounds tubules of coronal tooth dentin
- Intertubular dentin: lies between tubules, LESS CALCIFIED MATRIX, consists of
apatite crystals embedded within a collagen matrix
21.Why is dentin more susceptible to caries than enamel?: - less inorganic
content
- hydroxyapatite crystals are smaller
- more carbonated apatite
- greater numbers of impurities in crystals
- critical pH is higher than enamel
- tubules offer channels for diffusion of bacterial acids
22.The number and diameter of tubules increase from to the : DEJ -->
