Anatomy II - Mineralization

What two ions are necessary for mineralization?

calcium and phosphate

Biomineralization is

A) controlled process for localization, timing, and final structure

B) crystallization of ions without cellular stimulation

A) controlled process for localization, timing, and final structure

Calcification is

A) controlled process for localization, timing, and final structure

B) crystallization of ions without cellular stimulation

B) crystallization of ions without cellular stimulation

What is a cellular drive process?

A) biomineralization

B) calcification

A) biomineralization

What is a spontaneous, non-cellular drive process?

A) biomineralization

B) calcification

B) calcification

The crystallization of ions without cellular stimulation describes

A) biomineralization

B) calcification

B) calcification

The controlled process for localization, timing, and final structure through which mineral crystals are deposited in the matrix of living organisms describes

A) biomineralization

B) calcification

A) biomineralization

True/False: calcification is a cellular driven process

False

True/False: calcification is linked to inflammation and an attempt to repair tissue

True

What can cause demineralization of teeth?

food, drink, microbiota

What are characteristics of teeth that make it resistance to localized demineralization?

tooth structure and saliva

What type of collagen makes up more than 90% of the organic content in bone, cementum, and dentin?

A) type I

B) type II

C) type III

D) type IV

A) type I

What is the percentage of biological apatite in dentin and bone?

A) 25%

B) 45%

C) 50%

D) 55%

E) 75%

E) 75%

What is the percentage of biological apatite in cementum?

A) 25%

B) 45%

C) 50%

D) 55%

E) 75%

B) 45%

What shape is the crystalline structure of specialized connective tissue like bone, cementum, and dentin?

A) triangular

B) rectangular

C) hexagonal

C) hexagonal

True/False: enamel crystals are more organized, resistant to force, and generally stronger

True

If calcium ions in hydroxyapatite are replaced by magnesium or sodium, what change occurs?

A) inhibits crystal growth

B) decreases solubility

C) increases solubility?

A) inhibits crystal growth

If the hydroxyl group in hydroxyapatite is replaced by fluoride or chloride, what change occurs?

A) inhibits crystal growth

B) decreases solubility

C) increases solubility?

B) decreases solubility

If the phosphate and hydroxyl groups in hydroxyapatite are replaced by carbonate, what change occurs?

A) inhibits crystal growth

B) decreases solubility

C) increases solubility?

C) increases solubility

True/False: calcium phosphate is fundamental for the formation and maintenance of bone and teeth and is essential for achieving peak bone mass in the first 2-3 decades of life

True

What type of collagen acts as the structural protein of the matrix for dentin?

A) type I

B) type II

C) type III

D) type IV

A) type I

What acts at the organic matrix in dentin?

A) collagen

B) non-collagenous proteins

A) collagen

What acts as regulators of mineralization in dentin?

A) collagen

B) non-collagenous proteins

B) non-collagenous proteins

What are the three types of mineralization that occur in dentin?

- matrix vesicle derived

- ECM molecule derived

- blood/serum derived

What must be deposited in most cases prior to mineralization occurring?

A) collagen

B) non-collagenous proteins

C) hydroxyapatite

D) fluoride

A) collagen

What type of mineralization is done in mantle dentin?

A) matrix vesicle derived

B) ECM molecule derived

C) blood/serum derived

A) matrix vesicle derived

What type of mineralization occurs in most other dentin?

A) matrix vesicle derived

B) ECM molecule derived

C) blood/serum derived

B) ECM molecule derived

What type of mineralization occurs in peritubular dentin?

A) matrix vesicle derived

B) ECM molecule derived

C) blood/serum derived

C) blood/serum derived

Where does initiation of dentin mineralization occur?

A) intertubular dentin

B) peritubular dentin

C) mantle dentin

C) mantle dentin

Match the description with the type of mineralization:

Present at the onset of the outer dentin layers and contributes to the initiation and growth of the mineral phase. Chondroitin sulfate is a prerequisite for initiation of mineralization. Vesicles are released by odontoblasts near the DEJ.

A) matrix vesicle derived mineralization

B) ECM molecule derived mineralization

C) blood/serum derived mineralization

A) matrix vesicle derived mineralization

Match the description with the type of mineralization:

Occurs in three compartments: odontoblast cell bodies, predentin, and dentin. Native collagen, proteoglycans, SIBLINGs, and other non-phosphorylated proteins are involved.

A) matrix vesicle derived mineralization

B) ECM molecule derived mineralization

C) blood/serum derived mineralization

B) ECM molecule derived mineralization

Match the description with the type of mineralization:

Intercellular diffusion of albumin, a2-HS glycoprotein, choline-rich phospholipids. Contains an organic matrix mainly composed of glycosaminoglycans with proteoglycan binding segments. It provides stiffness and strengths porous tubules.

A) matrix vesicle derived mineralization

B) ECM molecule derived mineralization

C) blood/serum derived mineralization

C) blood/serum derived mineralization

Initiation of enamel mineralization requires mineralization of ____ for formation of initial enamel crystals (ribbons)

A) mantle dentin

B) peritubular dentin

C) intertuibular dentin

D) predentin

A) mantle dentin

True/False: enamel crystals often run parallel and continuous from the dentin crystals

True

What directs crystallite organization at the DEJ?

A) enamelin

B) amelogenin

A) enamelin

Describe the secretory stage of enamel formation and mineralization

- ameloblasts are attached to enamel mineral ribbons

- original orientation of enamel crystals establishes rod and interrod organization

- secretion of amelogenin helps expand volume of matrix and retrograde movement of ameloblasts

True/False: an influx of calcium and phosphorus are required during enamel matrix maturation

True

Demineralization is

A) removing minerals from hydroxyapatite crystals

B) restoring minerals to hydroxyapatite crystals

A) removing minerals from hydroxyapatite crystals

Remineralization is

A) removing minerals from hydroxyapatite crystals

B) restoring minerals to hydroxyapatite crystals

B) restoring minerals to hydroxyapatite crystals

What is the common pH that is associated with demineralization of enamel?

A) 2.0

B) 3.6

C) 5.5

D) 7.5

C) 5.5

True/False: the real critical pH is the pH of calcium and phosphate saturation

True

What are biological factors relating to demineralization and remineralization?

A) pH type, acid type, chelation potential

B) current health, socioeconomic status, medications

C) eating habits, drinking habits, brushing frequency

D) saliva flow, soft tissue anatomy, tooth anatomy

D) saliva flow, soft tissue anatomy, tooth anatomy

What are chemical factors relating to demineralization and remineralization?

A) pH type, acid type, chelation potential

B) current health, socioeconomic status, medications

C) eating habits, drinking habits, brushing frequency

D) saliva flow, soft tissue anatomy, tooth anatomy

A) pH type, acid type, chelation potential

What are health and education factors relating to demineralization and remineralization?

A) pH type, acid type, chelation potential

B) current health, socioeconomic status, medications

C) eating habits, drinking habits, brushing frequency

D) saliva flow, soft tissue anatomy, tooth anatomy

B) current health, socioeconomic status, medications

What are behavioral factors relating to demineralization and remineralization?

A) pH type, acid type, chelation potential

B) current health, socioeconomic status, medications

C) eating habits, drinking habits, brushing frequency

D) saliva flow, soft tissue anatomy, tooth anatomy

C) eating habits, drinking habits, brushing frequency

What is the most common acid that builds up and increases porosities and deeper diffusion between enamel in caries?

A) hydrochloric

B) lactic

C) phosphoric

D) acetic

B) lactic

What are the four factors that are required for progression of caries?

- plaque microorganisms, fermentable carbohydrates, susceptible tooth surface, time

True/False: if you take one of the factors required for progression of caries, the risk of caries stays the same

False

How do carbohydrates contribute to caries?

generation or organic acids through fermentation

What enzyme does fluoride inhibit that prevents caries by inhibiting fermentation of carbohydrates?

enolase

How do fermentable carbohydrates promote the growth of other bacteria?

expression of glucosyltransferase and glucan binding proteins

Erosion is

A) chemical dissolution of tooth substances without plaque

B) contact between occluding or approximal tooth surfaces leading to loss

C) loss of tooth structure by mechanical forces from foreign elements

A) chemical dissolution of tooth substance without plaque

Attrition is

A) chemical dissolution of tooth substances without plaque

B) contact between occluding or approximal tooth surfaces leading to loss

C) loss of tooth structure by mechanical forces from foreign elements

B) contact between occluding or approximal tooth surfaces leading to loss

Abrasion is

A) chemical dissolution of tooth substances without plaque

B) contact between occluding or approximal tooth surfaces leading to loss

C) loss of tooth structure by mechanical forces from foreign elements

C) loss of tooth structure by mechanical forces from foreign elements

Chemical dissolution of tooth substances without plaque describes

A) erosion

B) attrition

C) abrasion

A) erosion

Contact between occluding or approximal tooth surfaces that leads to loss describes

A) erosion

B) attrition

C) abrasion

B) attrition

Loss of tooth structure by mechanical forces from foreign elements

A) erosion

B) attrition

C) abrasion

C) abrasion

True/False: erosion is a cariogenic effect

False (just wears away tooth structure)

Intrinsic erosion results from

A) introduction of gastric acids into the oral cavity

B) diet, lifestyle, and/or environment

A) introduction of gastric acids into the oral cavity

Extrinsic erosion results from

A) introduction of gastric acids into the oral cavity

B) diet, lifestyle, and/or environment

B) diet, lifestyle, and/or environment

Erosion from diet, lifestyle, and/or environment is

A) intrinsic

B) extrinsic

B) extrinsic

Erosion from the introduction of gastric acids to the oral cavity is

A) intrinsic

B) extrinsic

A) intrinsic

What are conditions that can cause intrinsic erosion?

GERD, bulimia nervosa, chronic alcoholism, pregnancy

What are early signs of erosion?

- shallow pits or flattening of the lingual aspect

- pain if dentin is exposed

- scooping of dentin

What is treatment for extrinsic erosion?

- dietary and dental changes

- restoration or prosthodontic work

True/False: there is dentin scooping in attrition if no other SL causes are present

False

True/False: attrition can lead to enamel flaking and cusp fracture

True

What are causes of abrasion?

food, vigorous horizontal brushing, object biting, abrasive dentifrices or hard toothbrushes, denture clasps

True/False: scooping is present with abrasion

True

True/False: true remineralization is difficult

True

What are major sources of fluoride in the US?

drinking water, toothpaste and other dental products, and diet

What are ways fluoride gets into the body?

ingestion, inhalation

Adults in the US ingest or inhale nearly ___ mg/day outside of drinking water

A) 1

B) 5

C) 10

D) 15

A) 1

Where is fluoride absorbed?

lungs and digestive tract

How is fluoride excreted?

feces, sweat, milk, urine (primary)

True/False: fluoride is primarily absorbed through the oral mucosa

False

True/False: higher exposures to fluoride lead to a higher concentration in teeth later in life

True

True/False: a condition that affects urinary pH will have no impact on the amount of fluoride excreted

False

Where is the greatest concentration of F-?

A) outer surface of enamel

B) inner portion of enamel

C) cementum

D) dentin

A) outer surface of enamel

What has the lowest concentration of fluoride?

A) outer surface of enamel

B) inner portion of enamel

C) cementum

D) DEJ

E) dentin

D) DEJ

True/False: fluoroapatite is more insoluble causing enamel to be harder

True

True/False: fluoride can be can systemically and topically applied

True

What are mechanisms of action by which fluoride protects teeth?

forms more compact and regular crystals, high concentration on outer surface, binds protons at the surface, reduces number and sites where food and plaque accumulate, affects bacterial metabolism leading to molecule accumulation, increases hydroxyapatite by 4-8 times, influences rate of solubility, increases rate of maturation

High levels of fluoride can alter what cellular functions?

gene expression, signaling, migration, metabolism, transport mechanism

Children under 3 years should get what size of fluoride toothpaste on their toothbrush?

A) smear size

B) pea sized

C) cover the entire surface of the bristles

A) smear size

Children 3-6 years should get what size of fluoride toothpaste on their toothbrush?

A) smear size

B) pea sized

C) cover the entire surface of the bristles

B) pea sized

True/False: Children under the age of 3 should get a pea-sized amount of toothpaste on their toothbrush

False

Acute fluoride toxicity is mostly due to what effects?

- hydrofluoric acid corrosive action

- impeding nerve function

- inhibition of enzyme pathways

- impeding cardiac function

Chronic toxicity of fluoride is associated to what disorders?

renal abnormalities, skeletal fluorosis, osteosclerosis

Dental fluorosis can be observed if more than ____ mg of fluoride is found in drinking water

A) 0.5

B) 1.0

C) 1.5

D) 2.0

D) 2.0

Amelogenesis imperfecta is characterized by

A) hypoplasia and/or hypomineralization of enamel formation

B) dentin formation affects

C) brittle bones

A) hypoplasia and/or hypomineralization of enamel formation

Dentinogenesis imperfecta is characterized by

A) hypoplasia and/or hypomineralization of enamel formation

B) dentin formation affects

C) brittle bones

B) dentin formation affects

Osteogenesis imperfecta is characterized by

A) hypoplasia and/or hypomineralization of enamel formation

B) dentin formation affects

C) brittle bones

C) brittle bones

True/False: amelogenesis is only autosomal dominant

False (AD, AR, sex-linked)

If teeth look discolored or translucent, this might be

A) osteogenesis imperfecta

B) dentinogenesis imperfecta

C) amelogenesis imperfecta

B) dentinogenesis imperfecta

What type of dentinogenesis imperfecta is associated with osteogenesis imperfecta

A) type I

B) type II

C) type III

D) B and C

A) type I

What type of dentinogenesis imperfecta is associated with DSPP?

A) type I

B) type II

C) type III

D) B and C

D) B and C

Osteogenesis imperfecta is a mutation in

A) AMELX

B) DSPP

C) COL1A1, COL1A2

C) COL1A1, COL1A2

A DSPP mutation (assoc. w/ matrix and mineralization) is associated with

A) amelogenesis imperfecta

B) dentinogenesis imperfecta

C) osteogenesis imperfecta

B) dentinogenesis imperfecta

Amelogenesis imperfecta is associated with mutations in

A) AMELX, ENAM, MMP20, FAM83H

B) DSPP, COL1A1, COL1A2

C) COL1A1, COL1A2

A) AMELX, ENAM, MMP20, FAM83H