Physical factors as Physical factors as causes of diseasescauses of diseases

Mechanical energyMechanical energy

Injuries and woundsInjuries and wounds

• injury – trauma• wound – vulnus (pl. vulnera)

• woundsvulnus punctum - stabbed woundvulnus scissum - incised woundvulnus sectum - cut woundvulnus laceratum – lacerated woundvulnus contusum – contused woundvulnus sclopetarium – bullet woundvulnus morsum – bite woundvulnus venenatum – poisoned wound

• other injuriescommotio - concussioncontusio - contusionruptura – rupture, splittingdistorsio - distorsionluxatio - dislocation of the jointfractura – broken boneulcus - ulcerdekubitus – decubitus, bed sore

Injuries and woundsInjuries and wounds

• symptoms of wound

pain – locationageindividual difference

bleeding – arterial venous capillary

• consequences and complications of wounds

traumatic shockinfection – locus minoris resistentiae – gas gangrene

tetanus – Clostridium tetaniembolia – fat (fractura), gas (lung

damage)pneumotoraxdamage of the NS – paralysis, epilepsy, dementianecrosisstress – vegetative symptoms -

tachycardiadeath – damage of brain, heart

Blast syndromeBlast syndrome

SSyndrome characterized byyndrome characterized by tissue damage induced by strong tissue damage induced by strong shock (pressure) waveshock (pressure) wave::

Consequences: Consequences:

1.1. primary primary – – the effect of pressure on tissuethe effect of pressure on tissue

- damage of the organs filled with air- damage of the organs filled with air

bleeding to the tympanic membranebleeding to the tympanic membrane (ear drum) and/or rupture(ear drum) and/or rupture

damage of the inner eardamage of the inner ear

damage of hollow organsdamage of hollow organs ((e.g. e.g. stomach, stomach,

intestineintestiness))

rupture of alveoli and pulmonaryrupture of alveoli and pulmonary capicapillllaryary

2. secondary – damage caused by the flying object (flying human 2. secondary – damage caused by the flying object (flying human

being being too) – wounds, fractura, ctoo) – wounds, fractura, commotio cerebriommotio cerebri

3. other – fire, fall of the building, intoxication, radiation3. other – fire, fall of the building, intoxication, radiation

Blast syndromeBlast syndrome

using of the Blast syndrome in using of the Blast syndrome in

medicinemedicine

extracorporeal litotripsy – using of a extracorporeal litotripsy – using of a

shock wave and its energy on shock wave and its energy on

destroying of gallstones or destroying of gallstones or

kidney stoneskidney stones

Crush syndromeCrush syndrome

SSyndrome characterized by tissue damage induced by yndrome characterized by tissue damage induced by compressioncompression

- compression of soft tissues – ischaemia, oedemacompression of soft tissues – ischaemia, oedema    - ischaemia-reperfusion injury – oxygen radicalsischaemia-reperfusion injury – oxygen radicals- traumatic shocktraumatic shock

- - anaerobic metabolizm anaerobic metabolizm release of myoglogin from cells release of myoglogin from cells cylindres of precipitated myoglobin cylindres of precipitated myoglobin damage of kidney damage of kidney acute renal failure acute renal failure uremia uremia death death

Vibration, noiseVibration, noise

vibrationvibration- pain – spine, extremitiespain – spine, extremities- osteoporosisosteoporosis- Raynaud´s syndrome – vasoconstriction – pale, Raynaud´s syndrome – vasoconstriction – pale,

cold finger, trophis changescold finger, trophis changes- neurosis, hypertensionneurosis, hypertension

noisenoise- above 50 dBabove 50 dB- acute very intensive noise – explosionacute very intensive noise – explosion

- short-lasting reduction of hearingshort-lasting reduction of hearing- rupture of tympanic membrane – deafnessrupture of tympanic membrane – deafness

- chronic exposure to noisechronic exposure to noise- vegetative syndromes – palpitations, nauseavegetative syndromes – palpitations, nausea- headache, insomnia, dizzinessheadache, insomnia, dizziness- loss of hearingloss of hearing

UltrasoundUltrasound

- frequency above 18 kHzfrequency above 18 kHz- tthhermal, mechanical effectermal, mechanical effect

- used in diagnosis and therapyused in diagnosis and therapy

ultrasound dental scaler

ultrasound toothbrush

AccelerationAcceleration

Acceleration–deceleration: sudden and quick changes

in movement speed or directions of the body in the space

acceleration = positive accelerationdeceleration = negative accelerationangular acceleration – acceleration during rotation of the body

intensive acceleration upward (plane, spacecraft)accumulation of the blood in the lower parts of body brain and retina deprived of blood supply „black shield“ unconsciousness

intensive acceleration downward (plane, spacecraft)accumulation ot the blood in the upper parts of body hyperaemia of brain and retina „red shield“

Kinetosis (sea sickness)

– manifestation of vestibular system dysfunction

– dysfunction is manifested by „stormy“ reaction of

vegetative nerve system dysbalance sympathetic

and parasympathetic nerve systems

Main symptoms: vegetative – pallor, sweating, nausea, vomiting, abdominal pain, hypersalivation, tachycardia, decrease of blood pressuresensory – dizzinessmotor – hypotonia, loss of coordinationpsychic – apatia, depresion, somnolence

Hypobaria and Hypobaria and hyperbariahyperbaria

Hypobaria

Atmospheric pressure on the surface of Earth – 101.3 kPa (760 torr or Hgmm)

The athmospheric pressure decreases parallel with the altitude

In high altitude (more than 3 km) – mountain disease – acutechronic

Hypobaria (in planes) – distension of gases in hollow organsmiddle ear painpain of perinasal cavitiespain and cramps in GIT

Hypobaria in dental medicine - expansion of gas in carious of improperly filled teeth – pain (barodontalgia)

Decompression sickness (caisson disease)Who is in risk? – underwater construction workers – deep sea divers

Mechanisms: – return too quickly to the surface causes a form of gas embolism – oxygen and nitrogen which are normally disolved in the blood come out and forme tiny bubbles called gas emboli

Consequences: – nitrogen bubbles may persist and obstruct blood vessels gas embolism

- in muscles, joints, tendons pain, necrosis - cyanosis and paresthesias in the skin

- tachypnoe, substernal pain, dry cough- bubbles in brain - unconsciousness

Hyperbaria in dental medicine - barotrauma of n. facialis – paralysis - barotrauma of n. trigeminus –hypoanaestesia of chin, maxillar teeth,

upper lip

caisson

hyperbaric chamber

Thermal injuryThermal injury

• scald (hot water)

Burns (combustio) 1.degree 2.degree 3.degree

combustio combustio combustio erythematosa vesiculosa escharotica

4. degree - carbonisatio

2. degree

blisters

3. degree

necrosis

Complications of burns• sepsis• burn shock• smoke inhalation• burn of the upper airways

Classification of burn injuries according to severity and range

clinical %BSABrating total deepsmall <20 0middle heavy 20 - 25 <10heavy 25 - 40 10 - 20critical >40 >20

BSAB - body surface area burned

18

4.5

9

1

9

4.5

18

4.5

4.5

9 9

4.5

9 94 .5

7

4 .5

7

4 .5

7

18 181

The rule of 9

Chilblain (congelatio)

1. degree - congelatio erythematosa

• vasoconstriction – ischemia, loss of sensitivity

• later: vasodilatation – paresthaesia (pricking)

2. degree – congelatio bullosa

• oedema - blisters

3. congelatio escharotica

• necrosis

Hypertermia

- warm and dry environment – dehydratation

heat cramps

heat exhaustion

-warm and wet environment – heat stroke (siriasis)-tachycardia, tachypnoea, low blood pressure-more than 40oC – fatigue, headache, vomitus, muscle cramps

-sunstroke (insolatio) – sunshine concentrated to the uncovered head(children, old men)

- headache, nausea, vomitus

Hypotermia

- temperature of body core less than 35oC

-risk factors

-age – newborn babies, old people

-health status – insufficient circulation, hypothyreosis, Addison disease

-alcohol

-signs - somnolence, rigidity of muscles - decrease of heart and respiratory rate - uncoscioussness

-Immersion cooling-hyportermia in cold water

Electrical currentElectrical current

Damage caused by electrical currentAlternating electric current is dangerous for living organisms,

only when its parameters are - more than 50 V, more than 75

mA

Consequences: -thermal damage burns

due to resistance – dry skin burns

- depolarisation of the cells nervous cells – brain unconsciousness

heart cells – arrhythmia

muscles - cramps

- mechanical damage dysruption of skin and muscles

• Ohm´s law

I = UR

I – intensityU – voltageR - reistance

• burns caused by electrical current

Electromagnetic fieldElectromagnetic field

Radio waveseffects

- headache- psychic fatigability

Microwaveseffects

- increased cell metabolism

- thermal effect – vasodilatation, hyperaemia

Infrared waveseffects

- deep thermal effect - chronic exposure - cataract (glass-blower´s cataract

Visible lighteffects

- retinal burns – blindness

Ultraviolet lightUVA - 315 - 380 nm

UVB - 280 - 315 nm

UVC – 100 - 280 nm

Effects of UV light on the skin

early – inflammation, sun tanning, sunburn, hyperplasia, synthesis of vit. D

late – ageing, sun allergy, photocarcinogenesis