Endocrine Disorders W3 Flashcards
The endocrine system is the body’s main communication system, composed of glands, tissues and organs that release hormones into the blood stream.
How is it linked to the nervous system?
Linked to the N.S by hypothalamus… *Hypothalamic pituitary axis*
Hypothalamus controls pituitary gland, pituitary regulates realease of hormones from other glands
Compare and constrast the N.S and Endocrine system
N.S
- messengers = electrical impulses and neurotransmitters through neurons
- brain and spinal chord
- voluntary and involuntary control
- localised responses, fast, short lived
Endocrine
- messangers = hormones through blood
- glands and organs
- involuntary control
- widespread responses, slow, long lasting
What are the structures of the endocrine system
Glands: pituitary, thyroid, parathyroid, adrenal and pineal glands, thymus, pancreas, gonands
Other tissues and organs: adipocytes, cells in small intestine, stomach, kidneys and heart
What is the control centre of the endocrine system
The hypothalamus realeases hormones which stimulate release of hormones from pituitary
What is the main form of feedback that regulates endocrine hormones
- Negative feedback: keeps concentration of a hormone within relatively narrow range
= maintains homeostasis - Positive feedback: causes concentration of hormone to become increasingly higher: only for oxytocin
Describe how Calcium levels are controlled using negative feedback
Increased Ca2+ in blood
= Thyroid releases calcitonin
= osteoclast inhibited + Ca2+ reabsorbtion by kidneys decreases
= Ca2+ level in blood decreases
Decreased Ca2+ in blood
= Parathyroid releases PTH
= osteoclast reabsorb bone (release Ca2+) + Ca2+ reabsorbed from urine by kidneys and small intestine
= Ca2+ level in blood increases
List and describe the 3 classifications of cause for hypo-/hyper-function
Primary: originate in the gland responsible for producing the hormone ex. tumour
Secondary: defective levels of tthe stimulating hormones or releasing factors but normal gland function ex. GFRH from hypothalamus
Tertiary: result from hypothalamic dysfunction, affecting pituitary function
What hormones are released from the anterior and posterior pituitary?
G - growth hormone (anterior)
O - oxytocin (posterior)
A - antidiuretic hormone (posterior)
T - thyroid stimulating hormone (anterior)
F - follicle stimulating hormone (anterior)
L - luteninsing hormone (anterior)
A - adrenocorticotropic hormone (anterior)
P - prolactin (anterior)
Describe the symptoms and possible causes of Hypopituitarism
Underproduction of hormones released by the pituitary gland
- Usually gradual in appearence of signs
- Symptoms depend on WHICH hormones under-secreated but common ones = chronic unfitness, weakness, faitgue, loss of appetite, cold intolerance, sexual dysfunction
- Caused by tumours, acidental damage (radiation or surgery)
What is Panhypopituitarism
When ALL hormones secreted by the pituitary gland is disturbed
What is another name for growth hormone and where is it secreted from
Somatotropin or Somatropin
Released by pituitary
What do normal levels of growth hormone do?
Influences height, helps build muscles and bones
- boosts proliferation of cells and regeneration of tissues
- promotes healthy growth and weight gain in children and adolescents
- augments bone density and muscle mass
- ensures balance of body fluids (fats, water, blood)
- controls glucose synthesis, uptake and protein/lipid metabolism
- boosts energy levels/productivity/cognitive function/brain health
Describe the symptoms of GH deficiency in children/adolescents
Affects physical development - linear bone growth
Delays puberty- normal intelligence
Affects function of liver protein = short stature and immature facial features
Describe the symptoms and possible cause of GH deficiency in adults?
Symptoms…
- destruction of bone cells = fractures and osteoporosis
- affects metabolism
Possible cause…
- lack of GHRH or lack of GH secreating cells ie. non-functional tumours
What are the impacts on the oral cavity in children with GH deficiency
- md and mx growth effected
- tooth root and development of supporting structures retarded
- malocculsion, smaller arches
- delays in erupion and shedding
Describe the symptoms and possible cause of GH excess (acromegaly) in adults?
Acromegaly!
- Jaws, fingers, toes are bigger and bones become thicker
- forehead bosses and slants
- lower jaw protrusion
- flaring and spacing of anterior teeth
- enlarged soft tissues (tongue, liver, kidneys)
- Spiky exostosis- growths in alvelor bone.
- increased risk of diabetes
Possible causes…
- slow growing pituitary adenoma (tumour)
- headaches, poor vision, heart failure, weakness
Describe the symptoms and possible cause of GH excess in children (pituitary gigantism)
Pituitary gigantism
- abnormally large height and weight at young age
- rapid growth of all body tissues
- hyperglycaemia (overactive B cells) - type 2 diabetes
- death in early adulthood
Possible causes…
- acidophillic growth hormone-producing cells are excessively active or have acidophilic tumour
What are the impacts on the oral cavity in adults with GH excess (acromegaly)?
- Mandibular prognathism and thickening
- incerased thickness and height of alveolar process
- spacing and flaring of anterior teeth
- malocculsion
- enlarged tongue
Dentists well placed for early identification
Describe the symptoms of ADH deficiency in adults
Diabetes insipidus…
- excessive water loss
- drink alot and pee alot
- xerostomia
What do normal levels of ADH (vasopressin) do?
Regulate water balance
- act on kidneys to promote water reabsorption from forming urine (smaller amt/concentrated urine)
- cause vasoconstriction/raises BP
Synthesised in Hypothalamus: released by posterior pituitary in response to increased plasma osmolarity (high salt).
Describe the components of the ‘thyroid system’ ie. glands and hormones involved
Hypothalamus - TRH (thyrotopin releasing hormone)
Anterior pituitary - TSH (thyroid stimulating hormone)
Thyroid gland - Thyroid hormones T3 (Triiodothyronine) & T4 (thyroxine)
What do normal levels of T3 & T4 do
Increased metabolism and protein synthesis
- Effect growth and deveopment (including mental deveopment)
- Increased catecholamine effect
What is the stimuli for TRH release
- Cold
- Stress/emotional reactions
- Sleep
Grave’s Disease is known to cause hyperthyroidism:
Describe the symptoms and possible causes of hyperthyroidism in adults
Symptoms…
- increased skin temp and excess sweating
- tachycardia/irregular heart rate
- tiredness, muscle weakness, difficultly sleeping
- twitching/trembling
- anxiety
- exophthalmos (protruding eyes)
- increased sensitivity to catecholamines
Possible causes…
- High T4 (thyroxine)
- Graves disease (autoimmune disorder assoc. with thyroid-stimulating antibodies) (high TSH)
- toxic goitre (enlargment of thyroid)
- adenoma (tumour)
What is Thyrotoxicosis
Syndrome caused by high levels of thyroid hormone
- normally due to hyperthyroidism
What are the impacts on the oral cavity of hyperthyroidism
- more susceptible to peridontal disease & caries
- sensitive to adrenaline (L.A’s) -> hypertensive crisis?
- stress assoc. exaserbate cardiovascular issues
big concern = thyroid storm ie. thyrotoxic crisis (life threatening)!
What are the two possible causes of hypothyroidism
Aquired
- due to surgury, drugs ie. lithium, excess or lack or iodine
- Hashimotos thyroditis: autoimmune reaction destorys thyroid
Congenital
- causes cretinism (physical deformity and mental retardation)
Describe the symptoms of hypothyroidism in adults
Hypometabolism
- fatigue, weight gain despite loss of appetite
- cold intolerance
- myxedema (puffy appearance)
- pericardial or pleurral effusion (build up of fluid)
What are the impacts on the oral cavity of hypothyroidism
- Enlarged gingiva, salivary glands and tongue
- Dysgeusia (taste disorder)
- Delayed eruption
- Poor peridontal health
Considerations for dentists: caution iodine, and be careful with adrenaline because of cardiovascular issues
Describe the symptoms and possible cause of hyperparathyroidism in adults
Symptoms…
- bone lesions assoc. with excessive osteoclast activity
- hypercalcaemia
- increased tooth mobility and malocclusion (first signs)
Possible causes…
Neoplasia (uncontrolled growth)
Label this diagram and what are the other tissues/organs that have endocrine function?
Pockets of cells in the walls of the small intestine, the stomach, kidneys and heart
When hormones are released from endocrine tissues, how do they get to their target tissues to produce their responses?
Hormones are released into the bloodstream from endocrine glands and travel via bloodstreams to target tissues.
What is the main role of parathyroid hormone? What is the stimulus for its release?
Parathyroid hormone increases Ca2+ in the blood.
Stimulated in response to low Ca2+ in the blood.
PTH signals osteoclasts to breakdown the bone and release Ca2+ in the blood.
What hormone is secreted by the adrenal medulla?
catecholamines, progesterone
What hormones are released as part of the adrenal cortex?
mineralocorticoids (aldosterone)
glucocorticoids (cortisol)
adrenal sex hormones
What is the main function of aldosterone (mineralocorticoids)?
What are symptoms of its deficiency?
Maintains Na+ and water balance by reducing excretion of them from body.
By increasing the retention of Na+ and water by the kidneys.
Deficiency: dehydration, low BP, fatigue
What are some of the main actions of cortisol?
Helps body cope with stress.
Maintains blood glucose- gluconeogenisis in the liver
Metabolism: FA mobilisation, protein catabolism
IDENTIFY THE CONDITION:
Patient comes in and is stressed all the time and is noticeably anorexic. She mentions to you also that she is hypoglycemic.
Adrenal cortisol insufficiency- specifically, Glucocorticoid deficiency.
Limits body’s ability to deal with stress.
Bone growth during our childhood and teenage years is under delicate hormonal control.
This a picture of identical twins, what is the explanation for the difference in their appearance?
Excessive growth hormone secretion before puberty- results in gigantism.
High levels of insulin-like growth factor IGF stimulates excessive skeletal growth- this condition is rare because the adenoma may be recognised and treated early.
See picture of twins. They are 5 years old and the sister is a normal height for her age. Can you explain what may be happening with her shorter brother?
Growth retardation from insufficient growth hormone secretion due to lack of GHRH from hypothalamus.
Why are dentists in a good position to pick up on undiagnosed acromegaly?
Mandibular protrusion (prognathism) and thickening
Increased thickness and height of alveolar process
Spacing and flaring of anterior teeth,
with associated malocclusion and
enlargement of tongue.
Also, cartilaginous structures of the respiratory tract become enlarged- bronchitis.
Thyroid hormone disorders are the second-most common endocrine disorder after diabetes. What are the main signs of hyperthyroidism (associated with Graves Disease)?
Increased skin temperature, sweating, tachycardia and nervousness, exophthalmos (bulging eyes)
How do you treat hyperthyroidism and avoid thyrotoxic crisis ?
Benefit from sedation
Very sensitive to LA’s and gingival retraction cords
Use NSAIDS with caution- increase thyroxine levels
Detect undiagnosed hyperthyroidism- tachycardia, muscle tremors and heightened anxiety + irritability.
In what patients do you need to use NSAIDS with caution?
Hyperthyroidism, patients in thyrotoxic crisis. Because they increase thyroxine levels.
Where do Thyroid stimulation hormones originate and what are the names of the thyroid gland hormones?
How do you inhibit thyroid hormone release?
Hypothalamus secretes TRH (Thyroid Releasing Hormone) to the pituitary gland and releases TSH to tell the thyroid to release T3 and T4
T3: Triiodothyronine
T4: Thyroxine
Negative feedback look, inhibiting TRH at hypothalamus to stop production of thyroid hormone release.
ACTH acts on the adrenal cortex to release cortisol and androgens. What do high levels of ACTH and Adrenal Cortical Insufficiency a sign of?
Addison’s disease- serious but rare condition.
Too little cortisol.
High ACTH = Hyperpigmentation of the skin- gums and oral mucous membrane becomes bluish
Low cortisol (Glucocorticoid lack) = poor stress tolerance, hypoglycaemia, weakness, nausea and vomitting
Low Mineralocorticoid aldosterone = results in dehydration, low blood pressure and fatigue
What is Cushing’s syndrome?
Glucocorticoid excess- associated with excessive levels of ACTH stimulation caused by adrenal tumor.
Too stressed. Hyperglycemia (too much glucose in the blood).
What is the main concern for dentists who have a patient with Cushing’s Syndrome.
Immune suppression and increased risk of infection
Why should dentists be careful with patients who have asthma?
If they are inhaling corticosteroids they are advised to wash their mouth before treatment. Because corticosteroids can suppress immune function - increase the risk of infection.
If person presents with these physical features and easily to bruise skin, what can you assume their condition is? Describe these signs.
Cushing’s syndrome- exaggerated actions of cortisol.
Altered fat metabolism and abnormal fat distribution
Rounding of face- puffiness
Skin becomes thin and bruises easily
Osteoporosis due to Ca2 reabsorption
Immune suppression and increased risk of infection
Outline the role of the adrenal gland plays in helping the body deal with stressful situations. Are there differences between acute and chronic stress situations?
The glands make cortisol.
Adrenal medulla secretes hormone adrenaline: increases your heart rate, elevates your blood pressure and boosts energy supplies.
Adrenal cortex secretes hormone cortisol: helps maintain and raise blood glucose levels. Cortisol has anti-inflammatory properties. Chronic inflammation leads to disease. Addison’s disease- causes autoimmune destruction.
Oestrogen and progesterone can influence oral health, but their negative effects are mainly seen during pregnancy.
What is meant by pregnancy gingivitis, and why may it occur?
75% of women develop pregnancy gingivitis- red swollen and bleeding gums.
Due to oestrogen- increase vascularisation (new blood vessels)
Progesterone- vasodilation (widening the blood vessels) and vascular permeability (oedema)
Historically, there was been a tendency for women to avoid dental therapy during pregnancy, because of concerns for their baby. However, good dental care during pregnancy may be beneficial for both the mother and child.
What are the common factors that may increase the risk of caries and dental erosion during pregnancy?
There is an increased risk of caries – mainly due to:
- Food cravings and snacking
- Reduced oral hygiene (↑gag reflex, fatigue etc)
- Morning sickness
- Hormone-induced xerostomia
What represents the more comfortable period for dental therapy during pregnancy, and why?
Between weeks 14-20
Prior to that, issues like morning sickness and an enhanced gag reflex make treatment uncomfortable.
Later in pregnancy, the physical size of the developing foetus can cause issues – cannot lie supine in the dental chair
What are some of the main precautions that need to be taken in terms of proving dental care during pregnancy?
Drug use during pregnancy is always a concern – exercise caution, particularly during 1st trimester
Lignocaine and mepivicaine have good safety records
A number of antibiotics (e.g. amoxycillin) and antifungals (e.g. nystatin) may be used
Paracetamol is the preferred analgesic – best to avoid NSAIDs during 1st and 3rd trimesters
Sedation should be avoided – if required nitrous oxide may be used with medical consultation
Oestrogens naturally help to protect against osteoporosis, by promoting the (A) of osteoclasts. Osteoporosis may be managed by anti-resorptive medications, such as (B)
What are the main concerns around these medications in terms of providing oral care?
A apoptosis
B bisphosphonates
Osteneocrosis of the jaw. This is non-healing exposed bone in the maxillofacial region, which may occur following oral surgery.
What is a treatment for adrenal cortical insufficiency?
Hormone replacement- but long term corticosteroid therapy over 14 days can suppress adrenal function and suppress the immune system.
Effective anaesthesia - sedation
What are the main symptoms of PCOS?
How can you test for it?
Acne, unwanted hair growth, weight gain, fatigue, infertility, irregular periods
Elevated LH and Low FSH in blood
What is the role of parathyroid?
Symptoms for : Hyperparathyroidism
What are the causes?
- Impacts nerve and muscle activity- controls the CA2 levels in the blood and is released in response to a drop in CA2 levels. Increases osteoclast activity.
- Excessive thirst, weak or broken bone, fatigue, nausea
- High calcium and parathyroid hormone levels in the blood- can lead to hypercalciema
What role does the thyroid have with Calcium in the blood?
Lowers Ca2 in the blood
Thyroid gland releases calcitonin which inhibits osteoclast activity → decreasing the Ca reabsorption in the kidneys.
Therefore kidneys stop reabsorbing Ca2.
What is this picture an indication of? Explain.
Hyperpigmentation in the palate and depapillation of the tongue.
Due to high ACTH levels in primary adrenal insufficiency.
What supplementary dose can dentists give patients who need help to cope with stress?
Corticosteroids
What is the menstrual cycle’s role in hormone fluctuations?
Particularly progesterone-
Bright red swollen gums, canker sores, transient menstrual gingivitis before period. Swollen salivary glands
In menopause the declining levels of oestrogen and progesterone have an impact on oral health. What are the three main impacts?
- Thinning of oral mucosa: increased risk of burning mouth syndrome and xerostomia.
- Periodontium more prone to inflammation
- Increased osteoclast activity: risk of osteoporosis and exacerbated alveolar bone reabsorption
Define osteoporosis vs osteonecrosis
Osteoporosis is a decrease in bone mass by diminishing hormone levels.
Oestrogens promotes apoptosis of osteoclasts = osteonecrosis, bone death.
What is the influence Glucocorticoid deficiency has on stress?
Limits body’s ability to deal with stress. Can’t react properly to stress
Altered sex hormones, particularly PCOS may impair
- Effectiveness of epithelial barrier to bacterial injury
- Affect collagen repair and maintenance
What is hypoparathyroidism and dental patient relation?
Low Ca2 in blood. Prone to caries. Underdevelopment of enamel
Who is at risk of adrenal crisis and what is it?
Adrenal crisis: low blood pressure, low blood glucose, high potassium.
Can’t increase cortisol- adrenal insufficiency.
Addison’s disease patients need good LA to reduce risk. Patients taking corticosteroids longer than 14 days are at risk too.
Causes of PCOS- what is happening in the body chemically. How could you identify if a patient may be at risk?
High cytokines, high androgens, high oestrogen’s.
Receeding gums, unexplained gingivitis,
What hormones comes from the medulla vs cortex of adrenal glands?
Medulla = catecholamines, progesterone
Cortex = mineralcorticoids (aldosterone), glucocorticoids (cortisol), sex hormones.
