mercury toxicity in dental office. the slides explain all side effect. also describe OSHA regulation .

2.  INTRODUCTION
 FORM OF MERCURY
 MERCURY EXPOSURE IN DENTAL OFFICE
 SOURCES OF MERCURY EXPOSURE
 MERCURY LEVELS
 SIDE EFFECT OF MERCURY
 ALLERGY
 TOXICITY
 TREATMENT
 MERCURY HYGIENE
 MERCURY FREE ALLOYS
 CONCLUSION

3. Mercury poisoning (also
Known as hydrargyria or me-
rcurialism) is a disease caused
By exposure to mercury or its
Compound .mercury (Hg) is a
Heavy metal occurring in several forms,
All of which can produce toxic effects in
High enough doses

4. EXISTS IN THREE CHEMICAL FORM
 Elemental mercury
 Inorganic mercury
 Organic mercury

5. - Most volatile
- Exist in liquid/vapor form
- Inhaled and absorbed into
lungs(80%) and GIT(0.01%)
- Most common form amalgam
restoration
- Exposure to this form can occur
due to accidental spillage of mercury
in dental office

6. - Normally mined as inorganic
sulfide ore
- Mainly in liquid form
- Can also exist in other form than
sulfide
- Irritating in nature
- Main route of entry is through
lung(80%)

7. - Mainly in the form of methyl
mercury
- Main route of entry is absorption
though GIT(95-98%) though food
- Used in fungicide and pesticide
- Found in vegetables , fruits and
grains
- Toxic in nature

8.  Amalgam raw material being stored
in use
 During trituration , insertion &
intraoral hardening
 Amalgam scrap
 During finishing & polishing
 Removal of old restoration

10. NEUROTOXICITY
NEPHROTOXICITY
TERATOGENICITY
DEATH

11. 0
50
100
90
75
30
10
4
AMALGAM VACCINES SEAFOOD INDUSTRY OTHER

13. Amount of mercury released
During manipulation of amalgam

14. OSHA
RECOMMENDED
TTLV=0.05mg/m³
MOST Dental office mercury level lie below 0.05mg/m³

16.  Allergy responses represent an
antigen-antibody reaction marked by
itching, rashes, sneezing, or other
symptoms
 Contact dermatitis or Comb's type IV
hypersensitivity reaction represent
the most likely physiologic side effect
to dental amalgam

17.  Usually small % age of people are
allergic to mercury, when such a
reaction has been documented by
dermatologist or allergist, an alternative
material (e.g. Composite or ceramic)
must be used unless the
reaction is self limiting (usually within
2 Wks)

18.  release of mercury induced an acute
reaction which resulted in erythematous
lesions, severe burning and itchy sensation
and difficulty in breathing
 skin patch test results indicated a very
strong positive reaction to mercury
 Amalgam restorations were replaced with
composite filling material

20. - Amount of exposure
- Length of exposure
- Length of mercury accumulation
in body
- Amount of accumulated mercury
- Overall health of the patient
( for detoxification)

22. FORM OF
MERCURY
ELEMENTAL INORGANIC METHYLME-
RCURY
ROUTE OF
EXPOSURE
INHALTION ORAL ORAL –FISH
CONSUMPTION
TARGET
ORGAN
CNS , Kidney
Peripheral
nervous system
KIDNEY, PNS C N S
LOCAL CLINICAL
SIGN
Lung ;bronchial
irritation
GI-irritation
Skin – irritation
ulceration
SYSTEMIC
EFFECTS
Kidney-
proteinuria
CNS –mood
change
PNS - Tremors
Kidney –
proteinuria,
Tubular necrosis
Is PNS
TREMORS
NUMBNESS
Developmental
Effects in fetus
And newborn.
CNS IN ADULT
TREMORS
PARAESTHESIA

25.  PSYCHOLOGICAL DISTURBANCES
-Fits of anger
-short term memory loss
-low self –esteem
-loss of self control
-sleepiness.
A person may also suffer from the loss of
ability to learn new thing or things that
require memorization

26.  ORAL CAVITY PROBLEMs
-Inflammation of the mouth
-loss of bone around teeth
-ulcerated gums and other areas in the
mouth
-Darkening of gums
-taste of metal
-Bleeding gums

27.  G.I.T PROBLEMS
-Cramps
-inflamed colon
-diarrhea
 C.V.S PROMBLEMS
-Weak pulse
-increase B.P
-Chest pain/feeling of pressure
in the chest area

28.  RESPIRATORY PROMBLEMS
-Weakness and problems with breathing
- Emphysema
-persistent cough
 NEUROLOGICAL PROBLEMS
-headaches
-vertigo
-tinnitus
- twitching in various areas of the body
(eyelid, feet etc.)

30. Toxic effects include damage to the
brain, kidney and lung. Mercury poisoning
can result in several diseases,
including:-
 Acrodynia (pink disease)
 Hunter- russell syndrome
 MINAMATA DISEASE

31.  Peripheral neuropathy (Presenting
as paresthesia / itching, burning or
pain)
 skin discoloration
 swelling
 Desquamation(shedding of skin)
Sign and Symptoms

32. • Bleeding gums
• Alveolar bone loss
• Loosening of teeth
• Excessive salivation
• Foul breath
• Metallic taste
• Burning sensation, with tingling of lips, face
• Tissue pigmentation(amalgam tattoo of
gum)
• Stomatitis (sore in the mouth)
• Ulceration of gingiva, palate, tongue
Mercury symptoms on oral cavity

33.  Considered to be a mercury allergy
o Erythema of the palms soles
o Edema of hand and feet
o Desquamating rash
o Hair loss
o Pruritus
o Diaphoresis
o Tachycardia, hypertension
o Photophobia
o Irritability - Constipation/Diarrhea
o Anorexia
o Insomnia
o Poor muscle tone

35.  Syndrome is characterized by
paresthesia,
visual field constriction, ataxia, impaired
hearing, and speech impairment.

36.  Mercury in the marine environment
identified as a health risk for humans-
 MINAMATA DISEASE
 In 1952 a factory in minamata Japan
was mercury as a catalyst
--mercury washed into bay
 In 1953 fisherman and farmers
showed symptoms-neurological
damage and fetal deformity

37.  Disease diagnosed in 1956
- linked to fish consumption
 1957 fishing banned in area
 1959- mercury identified as
cause
 1960 source identified
- factory effluent

38. Symptoms were:-
1.ataxic gait
2.convulsions
3.numbness in mouth & limbs
4.constriction in the visual field
5.difficulty in speaking

44. Chelation therapy is the administration of
chelating agents remove heavy metals from
the body.
 A chelating agent could be given orally, I.M, I.V
 DMSA(FDA approved use in children for treat-
ing Hg toxicity
 2,3-DIMERCAPTO-1-PROPANESULFONIC
ACID(DMPS)
 D-PENCILLAMINE(DPCN) OR DIMERCAPROL
(BAL)

46. 1. Ventilation: provide proper ventilation in the
place by having fresh air exchanges and
periodic replacement of filters, which may
act as traps for mercury
2. Monitor office: monitor the Hg vapor
level in the office periodically. This may be
done by using dosimeter badges & vapor
analyzer(Limit – 50µg/m³ 8 hr shift over 40
hr work week)

48. 3. Monitor personnel: monitor office by
periodic analysis
4. Office design: use proper work area
design to facilitate spill containment
and cleanup
5. Pre-capsulated alloys: use pre-capsulated
alloy. Eliminate the possibility of a bulk Hg
spill, otherwise store bulk Hg properly in
unbreakable containers on stable surface

49. 6. Amalgamator cover: use an amalgamator
fitted with a cover
7.Handling care: use care in handling amalgam
avoid skin contact with mercury or freshly
mixed amalgam .avoid dry polishing.
8. Evacuation systems: use high volume evacuation
when finishing or removing amal-
gam .evacuation system have traps or
filter. Check, clean / replace traps and filter
periodically

51. 9. Masks: Change mask as necessary when
removing amalgam restoration.
10. Contaminated items: Dispose of Hg
contaminated items in sealed bags according
to applicable regulation
11.Spills: clean up Hg properly by using bottle
tapes/ fresh mixes of amalgam to pick- up
droplets/ use commercial clean up kits. Do
not use household vacuum cleaner.

54. 12. Clothing: Wear professional clothing
only in dental operatory
13. Select an appropriate alloy: Proper
Hg: alloy ratio to avoid the need to
remove excess Hg before packing.
14. Recycling: store amalgam scrap under
radiographic fixer solution in covered
container. Recycle amalgam scraps
through refiners

56. 15. Avoid carpet/floor coverings in dental
office ; floor coverings should be easy to
clean, nonabsorbent and seamless.
16. Follow aseptic technique, i.e. wear
protective mask, gloves and glasses to
prevent exposure to mercury vapors.
17.Use rubber dam during insertion,
condensation, and polishing of amalgam.
18. Dentists and dental assistants should have
proper knowledge of amalgam disposal and
their handling.

58. Gallium based alloy
- Gallium was discovered in 1875 .it is metal
With similar atomic structure and characteristics
To mercury and has a melting temp of 29˚c. Hence , by 1928 Puttkammer
suggested Gallium as a substitute for mercury
-- its available as a
1. Gallium Alloy
2. Galloy
 DISADVATAGES
. Handling characteristics of alloy not favorable
. High level of corrosion is seen which causes loss of strength
marginal disintegration and marginal fracture in chunks.
. Dimensional change of 21.5%
. Poor biocompatibility
. costly
 MERCURY FREE DIRECT FILLING ALLOY
 Ag Coated Ag-Sn particles which can be self compacted
MERCURY FREE ALLOYS

59.  Dental amalgam are still widely used by the
dental profession in most parts of the world.
 Some countries, like Sweden, Canada and
Germany, UK have either banned or imposed
serious limitations on amalgam usage.
 In the 1990s, several governments evaluated
the effects of dental amalgam and
concluded that the most likely health effects
would be due to hypersensitivity or allergy.

60.  In 2004,the Life Science Research Office
analyzed studies related to dental amalgam.
They took mean urinary mercury concentration
(µg of Hg/L in urine, HgU) as the most reliable
estimate of mercury exposure. 95 % of study
participants showed µg HgU below 4 to 5.
 Chewing gum, particularly for nicotine, along
with more amalgam, However, the WHO states
mercury levels in biomarkers such urine, blood
, hair do not represent levels in critical organs
and tissues.

61.  The American Dental Association
Council on Scientific Affairs has
conclude that both amalgam and
composite materials are considered safe
and effective for tooth restoration.