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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.
2
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
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
3
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)
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
4
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.
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
5
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
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
6
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
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
7
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.
8
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.
9
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.
10
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
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
11
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.
12
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
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
13
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
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
14
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
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
15
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.
16
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.
17
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
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
18
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
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
19
Hyperstates: Magnesium
 No evidence of overconsumption of magnesium
from food sources
 Kidney regulates magnesium, and toxicity may
cause kidney failure
 Symptoms:
 Diarrhea
 Nausea
 Cramping
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
20
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
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
21
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
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
22
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
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
23
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
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
24
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
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
25
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)
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
26
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.
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
27
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
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
28
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
Copyright © 2015, 2010, 2005, 1998 by Saunders, an imprint of Elsevier Inc.
29