OCCUPATIONAL HAZARDS IN DENTISTRY DUE TO DENTAL-

AMALGAM AND METHACRYLATES

Introduction:Dental Amalgam and Methacrylates are

materials used in the Dentistry and are called ‘restorative materials’.

Used when the teeth are decayed or have got traumatized.

Dental Amalgam = Mercury + Silver Alloy (Ag + Cu + Sn

etc;)

At least 50% of the final solid product Mercury!

Photo courtesy: http://www.samsondentalclinic.blosgspot.com

The Methacrylates used in dentistry are called ‘Composite Resins’ or simply ‘Composites’ which are used in ‘Tooth-colored fillings’.

HEMA, UEDMA, TEGDMA, BIS GMA etc;

‘Silver fillings’ & ‘White fillings’

Photo courtesy: http://www.wongdds.com/filling1.gif

The ‘Amalgam Controversy’An article published in the FASEB journal Wide-spread media attention

Extensive research being conducted to obtain conclusive evidence.

Photo courtesy: www.dentalamalgamguide.com

Occupational Hazards Amalgam

I. Routes of exposure:

- Skin contact- Breathing mercury vapor

II. Hazards:

I. CNS disorders- Psychosomatic symptomsExcessive salivation, sleeplessness, and loss of appetite

- Changes in emotional liabilityMood swings, irritability, fatigue, loss of interest,

withdrawal, sweating . .

- Diminished abilities to perform activitiesDue to lack of coordination, imbalance. . .

- Diminished abilities to perform fine motor movements

II. Reproductive disorders

III. Immunological disorders

III. Renal disorders

Methacrylates:

• Routes of Exposure:- Skin contact- Inhalation of methacrylate dust

Hazards:- Contact dermatitis (inflammation of the skin)

- Respiratory disordersWork-related cough & phlegm formation, increased risk of

adult onset asthma, respiratory hypersensitivity reactions

Preventive Measures:

Avoiding contact with the materials by use of appropriate PPE

- Usage of suitable gloves, mouth-masks, proper respiratory and eye protective equipment

Usage of instruments like ‘Amalgamators’.

Education on hazards to the dental personnel.

Testing for hypersensitivity.

Applicable laws

The EPA – responsible for regulating discharges into the environment

FDA – Responsible for regulating mercury content in drugs, cosmetics and medical devices (dental amalgam )

OSHA – Regulating workplace mercury and methacrylate levels & worker-exposure levels.

OSHA’s mandate for mercury exposure permissible in the work place

PEL 50 micrograms per cubic meter of air

The PEL for MMA is 100 ppm

Several states including New Hampshire, New York and Oregon, have introduced laws requiring dental offices to install amalgam separators on their wastewater discharges to prevent contamination

Countries which have totally banned the use of dental amalgams

- Norway, Denmark and Sweden

Conclusion:Very difficult to arrive to a conclusion on the

ill-effects of the use of dental amalgams for governments and health care organizations due to the lack of conclusive evidence in literature.

References: http://books.google.com/books?id=5uvuvNKpIkQC&printsec=fron

tcover&dq=Dental+materials+text+book&hl=en&ei=g3v-TLnhHIT78Ab65MSvBw&sa=X&oi=book_result&ct

Edlich RF, Greene JA, Cochran AA, Kelley AR, Gubler KD, Olson BM, Hudson MA, Woode DR, Long W.B., McGregor W., Yoder C., Hopkins D.B., Saepoff J.P. (2007). Need for informed consent for dentists who use mercury amalgam restorative material as well as technical considerations. Journal of Environmental Pathology and Toxicology 26 (4):305-322

World Health Organization, (2003). Concise International Chemical Assessment Document 50: Elemental Mercury and Inorganic Mercury Compounds: Human Health Aspects. Geneva, Switzerland

Jaakkola M. S., Leino T., Tammilehto L., Ylcstalo P., Kuosma E., Alanko K., 2007 Respiratory effects of exposure to methacrylates among dental assistants European Journal of Allergy and Clinical Immunology 2007: 62: 648-654. DOI: 10.1111/j.1398-9995.2007.01379.x Retrieved on November 26, 2010 from http://www.ncbi.nlm.nih.gov/pubmed/17508969