Endocrinal system /certified fixed orthodontic courses by Indian dental academy

Endocrinal System
Thyroid and Parathyroid

www.indiandentalacademy.com

INDIAN DENTAL ACADEMY
Leader in continuing dental education


Thyroid
• Endocrine gland situated in the neck.
• Two lobes joined by an isthmus.
• Secretes two hormones
Thyroxine(T3) and Triiodothtroxine(T4)


Regulation of thyroid gland
activity
• Thyroid gland is an effector component of
classic hypothalamic-anterior pitutaryperipheral gland axis.
• Major stimulator- TSH or thyrotropin from
anterior pitutary.
• Direct stimulator for TSH is TRH or
thyrotropin-releasing harmone from
hypothalamus.
• Negative feedback mechanism.

Actions of thyroid hormone
•
•
•
•

Whole body actions :
Increase the whole body consumption of
Oxygen and heat production.
Increase the cardiac output.
Accelerates the response to starvation.
Metabolic disposal of other hormones and
many drugs are increased.

Effects on growth and development
• Stimulates linear growth, development and
maturation of the bone.
• Accelerates secretion of growth hormone.
• Normal skeletal muscle function also
requires thyroid.
• Has critical effects on the development of
CNS.
• Contributes to the reproductive function of
both genders.

Disorders of thyroid function
• Hyperthyroidism :
• More common in women in the age range
of 20-40 years.
• Three conditions account for most cases
Grave’s disease
Toxic multinodular goitre
Solitary toxic nodule

• Clinical features :
• Characteristic eye changes- Exoptholmous,
limitation of ocular movement and
optholmoplegia.
• Increase in BMR
• Heightened level of anxiety and restlessness
• Intolerance to heat.
• Pretibial myxoedema

•
•
•
•
•
•
•
•
•

Management :
Antithyroid drugs – Carbimazole
Beta blockers
Radioactive iodine
Total or subtotal thyroidectomy.
Dental aspects :
GA is risky – chances of dangerous dysrythmias
Sedation may be necessary – N20 is safer
Risk of giving adrenaline containing LA is more
of theoretical risk.
• Thyroid crisis !!!

Hypothyroidism
• Commonest cause is chronic autoimmune
hypothyroidism- two clinical forms
Goitrous form (Hashimoto’s disease) &
Atrophic form
• Other causes – surgical removal, radiation,
iodine deficiency and some drugs.
• Common in women in the age group 60 yrs

• Often unrecognized
• Weight gain, lassitude, dry skin and loss of
hair.
• Bradycardia and heart failure.
• Neurological and psychological changes like
sleeplessness, irritability and mental dullness.
• Hoarseness,hypothermia and cold intolerance.
• Associated autoimmune disease like Sjogren’s
syndrome.

• Dental aspects :
• Main danger is of precipitating myxoedema
coma by sedatives(diazepam), opioids,
tranquillizers and general anaesthetics.
• Local anaesthesia is safe and preferrable.
• Stunted growth is most marked feature of
cretinism.Also eruption and shedding of
primary teeth are delayed.
• Additional problems may be posed by
associated hypopitutarism and Sjogren’s
syndrome. www.indiandentalacademy.com

Parathyroids
• Four pea-sized glands located on the back
of thyroid gland.
• Secrete parathyroid hormone(PTH).
• Secretion is controlled by negative feed
back mechanism. Stimulated by fall in the
plasma ionized calcium.

• Actions of PTH :
• Acts on kidneys, GIT and bone.
• PTH and vit D both act to control plasma Ca
levels.
• Increases renal re absorption of calcium and
impairs phosphate re absorption.
• Enhances GI absorption of calcium.
• Promotes osteoclastic bone resorption which is
reflected in a rise in plasma level of calcium and
alkaline phosphatase enzyme.

Hypoparathyroidism
• Most common cause is thyroidectomy.
• Muscle irritability and tetany is the classical
feature with
Facial twitching(Chvostek’s sign)
Carpopedal spasms(Trousseau’s sign)
Numbness and tingling of arms and legs
• Other uncommon features like
Psychiatric disorders
Dental defects
Constipation Etc.

• Diagnosis and management :
• Blood biochemistry
Low plasma calcium and often raised
phosphate.
• Therapy :
Replacement therapy includes Vit D and
calcium supplements. Vit D 500-3000
micrograms/day, Calcium 2-3 gms/day.


• Dental aspects :
• LA is safe
• Dental management may be complicated by
tetany, Seizures, psychiatric problems and
learning disabilities.
• Congenital forms may feature enamel
hypoplasia, shortened roots and sometimes
delayed eruption.


Hyperparathyroidism
• Three types –
Primary hyperparathyroidism : usually
caused by a parathyroid adenoma seen in
post menopausal women.
Secondary hyperparathyroidism : is a
response to plasma low calcium levels
secondary to chronic renal failure or
prolonged dialysis.
Tertiary hyperparathyroidism : follows
prolonged secondary hyperparathyroidism
that has become autonomous.

• “Stones, bones and abdominal groans”
• Hypercalcaemia leading to
Renal disease – renal calcifications (stones)
Skeletal disease – bone pain, pathological fractures and
giant cell tumors.
GI - Peptic ulcers and pancreatitis.
Others – hypertension and sometimes dysrhythmias.
• Hyperparathyroidism may sometimes be associated with
tumors of other endocrine glands
(MEN I, II and III).

• Diagnosis :
• Confirmed by raised parathyroid hormone
levels – raised serum calcium. Plasma
phosphate levels may be low.
• Enzyme alkaline phosphatase level will be
normal unless there is significant bony
involvement.
• Management :
• Surgical : Parathyroidectomy.
• Medical : active Vit D hormone(1,25dihydroxycholecalciferol). Also hydration,
increased salt intake and mild forced
diuresis.

Dental aspects
• LA is preferred over GA.
• Dental treatment may be complicated by
Renal disease – may impair drug excretion.
Peptic ulceration – may limit the choice of
analgesics.
Bone fragility – pathological fractures.
• Dental changes :
• Loss of lamina dura and generalized bone
rarefaction.
• Giant - cell lesions of hyperparathyroidism
(Browns tumor).

Thank you
Leader in continuing dental education


Endocrinal system /certified fixed orthodontic courses by Indian dental academy

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Viewers also liked

Viewers also liked (16)

Similar to Endocrinal system /certified fixed orthodontic courses by Indian dental academy

Similar to Endocrinal system /certified fixed orthodontic courses by Indian dental academy (20)

More from Indian dental academy

More from Indian dental academy (20)

Recently uploaded

Recently uploaded (20)

Endocrinal system /certified fixed orthodontic courses by Indian dental academy