The document discusses the toxicity of mercury, particularly from dental amalgam fillings. It provides background on mercury, noting that it can be absorbed from dental amalgam and negatively impact various body systems. It outlines the different chemical forms of mercury, sources of exposure, and pathways of absorption. The document details various side effects like allergic reactions and toxicity in multiple organ systems. It provides recommendations for safe mercury practices like proper ventilation, equipment, hygiene and removal techniques to reduce exposure and risks.

1. MERCURY
TOXICITY
PRESENTED BY-
DR. DHANASHREE GUNJAL
MDS, CONSERVATIVE DENTISTRY
AND ENDODONTICS.

2. Introduction
History
Chemical Forms Of Mercury
Sources Of Mercury Exposure
Pathways
Side effects of mercury
Mercury Hygiene
Safe Mercury Amalgam Removal Technique (SMART)
CONTENT
DR. DHANASHREE GUNJAL 2

3. Introduction
Mercury is a known toxic,
bio-accumulative substance.
It often finds its way into the body
through dental amalgam, which is used
to restore cavitated tooth.
Mercury release in body and shows
negative affect on the lungs, nervous
system, kidney etc.
DR. DHANASHREE GUNJAL 3

4. Definitions
An amalgam is an alloy that contains mercury as one of its constituents.
PHILLIP’S SCIENCE OF DENTAL MATREIALS 11TH EDITION
Dental amalgam is an alloy made by mixing mercury with a silver-tin dental
amalgam alloy.
STURDEVANT’S ART AND SCIENCE OF OPERATIVE DENTISTRY 5TH EDITION
DR. DHANASHREE GUNJAL 4

5. Amalgam Wars
• In 1841, the American
Society of Dental
Surgeons declared that
“the use of amalgam
constitutes
malpractice”
• Amalgam use declined
SECOND AMALGAM WAR
FIRST AMALGAM WAR THIRD AMALGAM WAR
• In mid 1920's a German
dentist, Professor A. Stock
started the "second
amalgam war".
• He claimed to have
evidence showing that
mercury could be absorbed
from dental amalgam,
which leads to serious
health problems.
• In 1981, the Neurobiologist
Mats Hanson, Assosiate
professor in physiology in
Sweden started the war.
• He was convinced that
mercury released from
dental amalgam was
responsible for human
diseases affecting the
cardiovascular system and
nervous system
DR. DHANASHREE GUNJAL 5

6. CHEMICAL FORMS
OF MERCURY
ELEMENTAL MERCURY
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
DR. DHANASHREE GUNJAL 6

7. Relative Sources Of Mercury Exposure
DR. DHANASHREE GUNJAL 7

8. Sources Of Mercury Exposure In Dental Clinic
• Amalgam raw material being stored in use
• During trituration , insertion & condensation
• Amalgam scrap
• During finishing & polishing
• Removal of old restoration
• Hg concentration in whole
blood is ↓10 μg/L,
• 20 μg/L / ↓ is normal.
• Blood Hg concentration can rise
to 35 μg/L after long-term
exposure to mercury vapor
DR. DHANASHREE GUNJAL 8

9. Hg released from
amalgam & inhaled with
80% uptake in the lung
Hg distributes
throughout cell and
tissue
By peroxidase oxidation Hg
breaks down to inorganic
mercury
Hg accumulates in the
nervous system, GIT,
liver and kidney
Hg excreted through
urine and faeces.
DR. DHANASHREE GUNJAL 9

10. Mechanism of mercury toxicity in the cell
DR. DHANASHREE GUNJAL 10

11. DR. DHANASHREE GUNJAL 11

12. Amount of Hg vapor released
• Trituration = 1-2 µg
• Condensation = 6-8 µg
• Dry polishing = 44 µg
• Wet polishing = 2-4 µg
• Removal of amalgam restoration under water
spray and high volume suction = 15-20µg
Threshold Limit Value(TLV) of mercury vapor in
workplace –50μg
DR. DHANASHREE GUNJAL 12

13. SIDE EFFECTS OF MERCURY
MERCURY
ALLERGY
MERCURY
TOXICITY
DR. DHANASHREE GUNJAL 13

14. Contact dermatitis or Comb's type IV hypersensitivity reaction
represents side effect to dental amalgam.
Allergy responses represent an antigen-antibody reaction
marked by
itching,
rashes,
sneezing,
erythematous lesions,
severe burning and
difficulty in breathing.
MERCURY ALLERGY
DR. DHANASHREE GUNJAL 14

15. Erythematous lesion on right buccal
mucosa in vicinity of amalgam
restorations.
Rashes on vermillion border of lower
lip, angle of mouth and cheek.
DR. DHANASHREE GUNJAL 15

16. • Immediate Hs reaction associated with the mercury
component of amalgam restoration induces an acute reaction.
• Skin patch test results indicated a very strong positive
reaction to mercury.
• Amalgam restorations should be replaced with composite
filling material.
MERCURY ALLERGY
DR. DHANASHREE GUNJAL 16

17. MERCURY TOXICITY
TOXIC EFFECTS OF MERCURY DEPEND UPON
Amount of exposure
Length of exposure
Length of mercury accumulation in body
Amount of accumulated mercury
Overall health of the patient (for detoxification)
DR. DHANASHREE GUNJAL 17

18. LEVELS OF MERCURY TOXICITY
DR. DHANASHREE GUNJAL 18

19. MERCURY
SYMPTOMS
ON ORAL
CAVITY
Tissue
pigmentation
Ulceration of
gingiva, palate
tongue
Bleeding
gums
Alveolar
bone loss
Loosening
of teeth
Foul breath
Metallic
taste
Stomatitis
Burning
sensation,
with
tingling of
lips, face
Excessive
salivation
DR. DHANASHREE GUNJAL 19

20. DR. DHANASHREE GUNJAL 20

21. TOXIC EFFECT OF MERCURY ON THE BODY
• Cramps
• Inflamed colon
• Diarrhea
G.IT PROBLEMS
• Weak pulse
• Increase B.P
• Chest pain/feeling of pressure.
• In the chest area
C.V.S
PROMBLEMS
• Weakness
• Emphysema
• Persistent cough
RESPIRATORY
PROMBLEMS
NEUROLOGICAL
PROBLEMS
• Headaches
• Vertigo
• Tinnitus
• Twitching
DR. DHANASHREE GUNJAL 21

22. Hg damaged development of CNS in the foetus during
prenatal period
DR. DHANASHREE GUNJAL 22

23. Classic symptoms:
tremor,
gingivitis,
Renal & CNS damage
Minamata disease
Mercury
Poisoning
Acute
effect
Chronic
effect
By ingestion:
local corrosive effects
nausea, vomiting,
severe abdominal pain,
chemical colitis, renal damage.
By inhalation:
chemical pneumonitis,
pulmonary edema
DR. DHANASHREE GUNJAL 23

24. • Erythema of the palms soles
• Edema of hand and feet
• Desquamating rash
• Hair loss
• Diaphoresis
• Tachycardia
• Photophobia
• Irritability- Constipation/Diarrhea
• Anorexia
• Insomnia
• Poor muscle tone
ACRODYNIA (PINK DISEASE)
DR. DHANASHREE GUNJAL 24

25. Caused by methylmercury poisoning
•Paraesthesia
•Visual field constriction
•Ataxia
• Impaired hearing & speech.
HUNTER RUSSELL SYNDROME
DR. DHANASHREE GUNJAL 25

26. MINAMATA DISEASE
DR. DHANASHREE GUNJAL 26

27. 1.Ataxic gait
2.Convulsions
3.Numbness in mouth & limbs
4.Constriction in the visual field
5.Difficulty in speaking.
MINAMATA DISEASE
DR. DHANASHREE GUNJAL 27

28. Ventilation
Monitor office
Monitor
personnel
Office design
• Proper ventilation by having
fresh air exchanges and
periodic replacement of
filters.
• Monitor the Hg vapor level
in the office periodically.
• Monitor office by periodic
analysis
• Use proper work area
design to facilitate spill
containment and clean up.
SAFE MERCURY AMALGAM REMOVAL TECHNIQUE
DR. DHANASHREE GUNJAL 28

29. Pre-capsulated
alloys
Amalgamator
cover
Evacuation
systems
• Use pre-capsulated Alloy.
Eliminate the possibility
of a bulk Hg Spill
• Use an amalgamator
fitted with a cover.
Use high volume
evacuation when finishing/
removing amalgam. It has
the traps/ filter.
DR. DHANASHREE GUNJAL 29

30. Masks
Contaminated
items
Spills
Select an
appropriate alloy
• Change mask as necessary
when removing amalgam
restoration.
• Dispose in sealed bags
according to applicable
regulation
• Clean up Hg properly by
using bottle tapes.
• To pick- up amalgam
droplets use clean up kits.
Proper Hg: alloy ratio to
avoid the need to remove
excess Hg before packing.
DR. DHANASHREE GUNJAL 30

31. Recyling
Clothing
Avoid carpet/floor
coverings in dental
office
• store amalgam scrap under
radiographic fixer solution in
covered container.
• Recycle amalgam scraps through
refiners
• Wear professional clothing
only in dental operatory.
• floor coverings should be
easy to clean, nonabsorbent
and seamless.
Use rubber dam during insertion, condensation and
polishing of amalgam
DR. DHANASHREE GUNJAL 31

32. DR. DHANASHREE GUNJAL 32

33. Gallium based alloy:-
Gallium was discovered in 1875.
It is metal with similar atomic structure and characteristics to mercury
Melting temp of 29°C.
By 1928, Puttkammer suggested Gallium as a substitute for mercury.
It is available as
1. Gallium Alloy
2. Galloy
Disadvatages:
Handling characteristics of alloy not favourable
High level of corrosion is seen which causes loss of strength marginal
disintegration and marginal fracture in chunks.
Poor biocompatibility. Costly.
TO REDUCE MERCURY HAZARDS:MERCURY FREE ALLOYS
DR. DHANASHREE GUNJAL 33

34. CHELATION THERAPY
•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
• FDA approved use in children for treating Hg toxicity
2,3-dimercapto-1 propanesulfonicacid (DMPS)
D-Pencillamine (DPCN)
Dimercaprol (BAL)
DR. DHANASHREE GUNJAL 34

35. • Phillips Science Of Dental Material 10th & 11th Edition
• Sturdevant s The Art and Science of Operative Dentistry, Fifth Edition
• Syed M, Chopra R, Sachdev V. Allergic Reactions to Dental Materials-A Systematic
Review. J Clin Diagn Res. 2015 Oct;9(10):ZE04
• Ryo Sasaki DDS PhD, Sekiko Taneda, Toshihha, Gingival amalgam tattoo,
CMAJ 2023 August 21;195:E1083-4.
• Rhythm Bains1, Kapil Loomba1 and Anju Loomba, Allergy to Mercury from
Dental Amalgam: A Case Report, Asian Journal of Oral Health & Allied Sciences
2012, Volume 2, Issue 2
• Dack K, Fell M, Taylor CM, Havdahl A, Lewis SJ. Prenatal Mercury Exposure and
Neurodevelopment up to the Age of 5 Years: A Systematic Review. Int J Environ
Res Public Health. 2022;19(4):1976.
REFERENCES
DR. DHANASHREE GUNJAL 35