Transcript Chapter_09R
MINERALS ESSENTIAL
FOR CALCIFIED STRUCTURES
CHAPTER 9
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
Bone Mineralization and Growth
Calcified structures include bones and
teeth
Collagen and bone undergo constant
remodeling
Organic matrix of bone is 90%–95% collagen
fibers
Formation of collagen requires protein,
vitamin C, iron, copper, and zinc
From Bath-Balogh M, Fehrenbach MJ: Illustrated
Dental Embryology, Histology, and Anatomy, ed
3. St. Louis: Saunders, 2011.
Once collagen is formed, mineralization begins
Calcium, phosphorus, magnesium, sodium,
potassium, and carbonate ions form mineral matrix
Calcium reserve: 0.4%–10% of total bone
calcium in shapeless (amorphous) form
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
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Formation of Teeth
Crystalline structure of enamel is
one of the most insoluble and
resistant proteins known
Comparable to hardness of quartz
Dentin contains the same
constituents as bone, but its
structure is more dense
Cementum is another bone-like
substance, but because it
From Nanci A: Ten Cate’s Oral Histology, ed
8. St. Louis: Mosby, 2013.
contains fewer minerals, it is
softer than bone
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Introduction to Minerals
Minerals are inorganic elements that have many
physiological functions
Inorganic elements in body account for only
about 4% of total body weight, or 6 lb for a 150-lb
person
Minerals subdivided into two categories
Those required in larger amounts (major minerals)
Those required in smaller amounts (micronutrients or
trace elements)
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Physiological Roles: Calcium
Most abundant mineral in the
body (~1200 g)
99% in teeth and bones
Functions
Bone health
Blood clotting
Transmit nerve impulses
Muscle contraction and relaxation
Membrane permeability
Activate certain enzymes
Salivary calcium acts as buffer
From Fehrenbach MJ, Herring SW: Illustrated Anatomy of the
Head and Neck, ed 4. St. Louis: Saunders, 2012.
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Requirements: Calcium
AI
9 to 13 y/o boys and girls
1300 mg/day
19 to 50 y/o men and women
1000 mg/day
51 to 70+ y/o men and women
1200 mg/day
Only 1 in 4 Americans meets AI
for calcium
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Requirements: Calcium
Current levels of intake
Males ages 9 and older
Average intake ~925 mg/day (71% of AI)
Females ages 9 and older
Average intake ~657 mg/day (51% of AI)
AI for those with self-diagnosed lactose intolerance
~320 mg/day (25% of AI)
At high risk of inadequate intakes to build
peak bone mass and prevent osteoporosis
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Calcium-to-Phosphorus Ratio
Serum levels of calcium and phosphorus
inversely related
If calcium level goes up, phosphorus level goes down
Ideal calcium/phosphorus ratio for adults is 1:1
Excessive intake of phosphorus compared with
calcium reduces serum calcium concentration
Calcium requirements are increased when
dietary phosphate is high as in the typical
American diet
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
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Absorption: Calcium
Absorption regulated by hormones (parathyroid,
estrogen, glucocorticoids, thyroid)
Best absorbed when consumed in smaller
amounts and ingested several times
during the day
Factors decreasing absorption:
Oxylates and phytates in grains,
vegetables
Reduced gastric acidity
Excessive fiber
Low-protein, low-phosphorus diets
From Patton KT, Thibodeau GA: Anatomy &
Physiology, ed 8. St. Louis: Mosby, 2013.
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
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Sources: Calcium
Milk and dairy products
Preferred sources of calcium because of high calcium,
lactose, and other nutrient content that enhances
calcium absorption
Fortified soy and rice milk
Other fortified foods (orange juice)
Supplements
Limited bioavailability
Better absorbed when taken with food
Calcium citrate malate, calcium lactate, calcium
citrate, and calcium sulfate have high absorption rates
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
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Hyperstates: Calcium
Hypercalcemia-excess calcium levels in the
blood
Caused by:
Hyperparathryoidism
Overdoses of cholecalciferol
Vitamin D poisoning
Excessive calcium intake results in:
Dizziness, flushing, nausea/vomiting, severe
constipation, kidney stone formation, irregular
heartbeat, tingling sensations, xerostomia, fatigue, and
high blood pressure
May inhibit iron and zinc absorption
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Hypostates: Calcium
Rickets
Abnormal ossification from
vitamin D, calcium deficiency
Osteoporosis
From Kumar V, Abbas AK, Fausto N: Robbins and
Cotran Pathologic Basis of Disease, ed 8.
Philadelphia: Saunders, 2010.
“Osteoporosis is a disease of adolescence”
90% of peak bone mass is attained by age 16.9 + 1.3 yr and
99% by age 26.2 + 3.7 yr
BMD associated with fractures in elder years, but also may
predict fractures in children
Inadequate calcium intake in early life accounts for as much as
50% of difference in hip fracture rates in postmenopausal years
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
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Hypostates: Calcium
Reduction in total skeletal mass is directly related to
reduction in mandibular bone density in women with
osteoporosis
Postmenopausal women who lost teeth also lost bone
mineral of the whole body and femoral neck at greater
rates than those who retained their teeth
Systemic bone loss appears to be a predictor of tooth loss in
dentate postmenopausal women
Inadequate calcium intake and periodontal disease
Study of NHANES data suggests a 56% risk of periodontal
disease with calcium intakes 500 mg/day
27% greater risk for those women consuming from 500 to
800 mg/day of calcium
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Physiological Roles:
Phosphorus
Phosphorus: second-most abundant mineral in
the body; about 85% in the skeleton and teeth
Functions
Formation of bones and teeth
Muscle contraction and nerve activity
Component of phospholipids in cell membranes, DNA,
and RNA
Energy metabolism (ADP)
Buffer for the body
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Requirement and Source:
Phosphorus
RDA
Men and women: 700 mg/day
Sources
Abundant in foods—deficiency rare
Best sources are milk products and meats
Food additive in baked goods, cheese, processed
meats, and soft drinks
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Hyperstates: Phosphorus
Hyperphosphatemia
(serum level above
2.6 mg/dl) may occur
in:
Hypoparathyroidism
Renal insufficiency
Excessive amounts of
phosphorus bind with
calcium, resulting in
tetany and
convulsions
From Patton KT, Thibodeau GA: Anatomy & Physiology, ed 8.
St. Louis: Mosby, 2013.
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
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Hypostates: Phosphorus
Long-term ingestion of aluminum hydroxide antacids
Stress conditions in calcium-to-phosphorus balance
Malabsorption conditions (sprue and celiac disease)
During tooth development, phosphorus deficiency
results in:
Incomplete calcification of teeth
Failure of dentin formation
Increased susceptibility to caries
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
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Physiological Roles:
Magnesium
Bones contain almost two thirds of body’s
magnesium
Role in bone and mineral physiology
Cofactor for more than 300 enzymes
Necessary for DNA and RNA synthesis
Regulates transmission of nerve impulses and
muscle contraction
Associated with vitamin D conversion in the liver
Facilitates blood clotting
Facilitates PTH secretion
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Requirements and Sources:
Magnesium
RDA (19 to 30 yr)
Men: 400 mg/day
Women: 310 mg/day
UL
350 mg/day from nonfood sources
Sources
Dark green, leafy vegetables
Whole grains and nuts
Chocolate
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Hyperstates: Magnesium
No evidence of overconsumption of magnesium
from food sources
Kidney regulates magnesium, and toxicity may
cause kidney failure
Symptoms:
Diarrhea
Nausea
Cramping
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Hypostates: Magnesium
Deficiency rare in healthy people
Can occur w/prolonged vomiting,
malabsorption, kidney disease, intestinal
surgery, excessive use of OTC and
medications (corticosteroids, diuretics)
Present in nearly all chronic alcoholics
Symptoms of deficiency:
Fragility of alveolar bone and gingival hypertrophy
Cardiac dysrhythmias
Neuromuscular hyperexcitability
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Nutritional Directions: Magnesium
Evidence suggests that magnesium may play
an important role in regulating blood pressure
The DASH study (Dietary Approaches to Stop
Hypertension) suggests HBP can be lowered by
diet high in magnesium, potassium, and calcium,
and low in sodium and fat
The diet includes whole grains, fruits, vegetables,
and low-fat dairy
http://dashdiet.org
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Overview: Fluoride
In a strict nutritional sense, fluoride is not a
nutrient essential for health because it has no
known metabolic function
However, because of benefits to dental and bone
health, fluoride is considered a desirable element
for humans
Fluoride ions can replace hydroxyl ions in the
hydroxyapatite crystal lattice, making it more
resistant to caries
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Physiological Roles: Fluoride
Forms fluorapatite, which is more caries resistant
Systemic fluoride results in changes to tooth
morphology; increases tooth’s resistance to
adherence of plaque biofilm
Fluoride in saliva also interferes with
demineralization
Higher concentrations of fluoride
From Bird DL, Robinson DS Modern Dental
Assisting, ed 11. St. Louis: Saunders, 2015.
inhibit Streptococcus mutans, Streptococcus
sobrinus, and Lactobacillus species
Stimulates osteoblast proliferation and increases
new mineral deposition in cancellous bone
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Requirements: Fluoride
Absorption occurs in the stomach
AI
6 to 12 mo: 0.5 mg/day
1 to 3 yr: 0.7 mg/day
2 to 8 yr: 1.1 mg/day
9 to 13 yr: 2.0 mg/day
14 to 18 yr: 2.9–3.2 mg/day
19+ yr: 3.1–3.8 mg/day
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Requirements: Fluoride
UL
6 to 12 mo: 0.9 mg/day
1 to 3 yr: 1.3 mg/day
4 to 8 yr: 2.2 mg/day
9+ yr: 10 mg/day
Sources
Fluoridated water
Brewed tea
Ocean fish w/bones (salmon, herring, sardines)
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Hyperstates: Fluoride
Dental fluorosis
(hypomineralization of enamel)
directly related to fluoride exposure
during tooth development
Varies from white flecks, to white or
brown staining, to brownish
discoloration and varying degrees of
enamel pitting
Ingestion of large amounts of
fluoride in adults can result in
adverse effects on skeletal tissue
and kidney function
Courtesy Alton McWhorter, DDS, MS;
Associate Professor Pediatric Dentistry;
The Texas A&M University System;
Baylor College of Dentistry; Dallas.
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Nutritional Directions
Encourage use of fluoridated water for those
>6 months of age and topical fluorides for
adults and children
Encourage low-fat dairy, whole grains, and
vegetables as calcium and magnesium sources
Evaluate use of supplements and refer to a
medical provider and/or registered dietitian as
needed
Stress need to minimize use of antacids and
seek medical care for chronic heartburn
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HEALTH APPLICATION
Osteoporosis
Discuss both overall & oral health impacts of
patients developing osteoporosis
Discuss demographic at risk for developing
osteoporosis
Discuss impacts of having osteoporosis on the
oral cavity
Discuss treatment options & adequate calcium
intake for prevention of osteoporosis
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