a simple but complete explanation about the physiology thyroid gland and the oral manifestations associated with it.

1. THYROID GLAND
Mohammed Sadeq
Akram Hatem
Hussain Ali Farhan
Mohammed Qasim

2. Glands
Endocrined
(Ductless)
Amino Acid
Steroids
Exocrine
(Ductfull)
Mucous
Serous

3. BASIC CATEGORIES OF ENDOCRINE
SYSTEM HORMONES
• Amino acid based: modified amino acids (or amines),
peptides (short chains of amino acids), and proteins (long
chains of amino acids)
• Steroid based: lipid molecules derived from cholesterol

4. OVERVIEW OF THE ENDOCRINE SYSTEM
System of ductless glands that secrete hormones in the blood
• It controls physiological processes and maintains homeostasis.
• Its response may be primary, with the release of neurotransmitters, or if
the stimulus prevails, the endocrine system secretes hormones.
• This is especially important in dentistry because many of the patients
attending the dental clinics face stressful situations.
• Awareness is therefore necessary of the risks and difficulties that may
arise during the dental management of patients with endocrine
disorders.

5. HORMONE RECEPTOR COMPLEX
peptide hormones Receptors tend to be cell surface receptors
built into the plasma membrane of cells and are thus referred to
as trans membrane receptors.
Steroid Hormones receptors are usually found within the
cytoplasm and are referred to as intracellular or nuclear receptors

6. ENDOCRINE SYSTEM’S GLANDS
Purely endocrine organs
Pituitary gland
Pineal gland
Thyroid gland
Parathyroid glands
Adrenal: 2 glands
Cortex
Medulla
Endocrine cells in other organs
Pancreas
Thymus
Gonads
Hypothalamus

7. SOME ENDOCRINE DISORDERS
AND THEIR EFFECTS IN
ORTHODONTICS.

8. ORAL MANIFESTATIONS OF PATIENTS WITH
THYROID GLAND DISORDERS
HYPERTHYROIDISM
Accelerated dental eruption in children
Maxillary or mandibular osteoporosis
Enlargement of extraglandular thyroid tissue
Increased susceptibility to caries
Periodontal disease
Burning mouth syndrome

9. ORAL MANIFESTATIONS OF PATIENTS
WITH THYROID GLAND DISORDERS
HYPOTHYROIDISM
Delayed eruption
Enamel hypoplasia in both dentitions.
Anterior open bite
Macroglossia
Micrognathia
Thick lips
Mouth breathing

10. ORAL MANIFESTATIONS OF PATIENTS WITH
PARATHYROID GLANDS DISORDERS
HYPERPARATHYROIDISM
Dental abnormalities:
- Widened pulp chambers
- Development defects
- Alterations in dental eruption
- Weak teeth
- Maloclussions
Brown tumor
Loss of bone density
Soft tissue calcifications

11. ORAL MANIFESTATIONS OF PATIENTS WITH
PARATHYROID GLANDS DISORDERS
HYPOPARATHYROIDISM
 Dental abnormalities:
- Poorly calcified dentin
- Widened pulp chambers
- Dental pulp calcifications
- Shortened roots
- Hypodontia
- Delay or cessation of dental development
 Mandibular tori
 Chronic candidiasis
 Paresthesia of the tongue or lips
 Alteration in facial muscles

12. ORAL MANIFESTATIONS OF THE PATIENT WITH
ADRENAL GLANDS DISORDERS (ADDISON’S
DISEASE)
The oral mucosa can in turn develop black-bluish plaques,
mainly affecting buccal mucosa but it can also be seen on the
gums, palate, tongue and lips.
Primary adrenal insufficiency

13. ANATOMY AND HISTOLOGY
OF THYROID GLAND

14. ANATOMY OF THYROID GLAND
• It is a butterfly shaped organ which is Located in the
anterior neck on trachea just inferior to larynx.
• Consists of two lobes connected by a narrow isthmus
with each lobe being about 5 cm long, 3 cm wide
and 2 cm thick, and the isthmus about 1.25 cm in
height and width
• It is brownish-red in colour due to high vascularity
• It is larger in females than in males

15. THYROID GLAND BLOOD SUPPLY
The thyroid is supplied with arterial blood from the
Superior Thyroid Artery, a branch of the External
Carotid Artery, and the Inferior Thyroid Artery, a
branch of the Thyrocervical Trunk
The venous blood is drained via Superior and
Middle Thyroid Vein, which drain to the Internal
Jugular Vein, and via the Inferior Thyroid Vein

16. THYROID GLAND NERVE SUPPLY & LYMPHATIC
DRAINAGE
Lymphatic Drainage frequently passes the
prelaryngeal lymph nodes (located just above the
isthmus), and the pretracheal and paratracheal lymph
nodes
Sympathetic Nerve Supply from the Superior, Middle
And Inferior Cervical Ganglion of the sympathetic
trunk. Parasympathetic Nerve Supply from the
superior laryngeal nerve and the recurrent laryngeal
nerve.

17. Thyroid is composed of
spherical follicles
Follicle cells: produce
thyroglobulin, the precursor
thryoid hormone (thyroxin)
Colloid lumen is of
thyroglobulin
Parafollicular “C” cells:
produce calcitonin
THYROID GLAND HISTOLOGY

18. PHYSIOLOGY OF THYROID
GLAND

19. THYROID GLAND HORMONES
Thyroid
Hormones
Thyroxin (T4)
Triiodothyronine
(T3)

20. PHYSIOLOGICAL EFFECTS OF THYROID GLAND
Regulation of metabolic body processes
 cellular respiration
 total energy expenditure
 growth and maturation of tissues

21. • Tyrosine and iodine are essential for
synthesis of thyroid hormones.
• Both are taken up by the blood
• Tyrosine is synthesized by the body (in
the thyroglobulin).
• Iodine is a dietary essential.
• Hormone synthesis occurs on the
thyroglobulin.
SYNTHESIS, STORAGE & SECRETION OF
THYROID HORMONES

23. REGULATION OF THYROID HORMONE SECRETION
> 4.12 mIU/L.

24. MECHANISM OF HORMONE ACTION

25. MECHANISM OF HORMONE ACTION

26. MECHANISM OF HORMONE ACTION

27. MECHANISM OF HORMONE ACTION

28. PHYSIOLOGICAL EFFECTS OF THYROID
HORMONES