Characterization of airborne particles from irreversible hydrocolloids

Our plain-English summary of Characterization of airborne particles from irreversible hydrocolloids, by R.D. Woody, E.F. Huget, D.E. Cutright (The Journal of the American Dental Association, 1977).

The study

• Authors: R.D. Woody, E.F. Huget, D.E. Cutright
• Journal: The Journal of the American Dental Association
• Published: 1977;94(3):501-4
• Cited by: 12 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Airborne particles of irreversible hydrocolloid powders were monitored and characterized. Ten to fifteen percent of the particles were siliceous fibers with dimensions of less than 3mum in diameter and more than 20mum in length. These dimensions conform closely to the dimensions of the fibrogenic and carcinogenic fibres of asbestos, glass, and aluminum oxide. With almost daily utilization of irreversible hydrocolloid materials in the dental office, the improper handling of the materials could be hazardous to the health of dental personnel. It is recommended that inhalation of aerosols arising from irreversible hydrocolloid powders be avoided.

In plain English

This laboratory study examined the dust given off by two brand-name alginate (irreversible hydrocolloid) dental impression powders, Jeltrate and Alginate. The authors tumbled each powder in a closed can, opened it, and collected airborne particles at the can opening and 30 cm above it. They also brushed powder directly onto slides and specimen holders. The particles were examined with light and scanning electron microscopes and analyzed by X-ray. Silicon was the main inorganic element, and the authors said the particles had the features of diatomaceous earth. In brushed samples, about 40% of particles were long hollow tubules. Thirty cm above the can, about 35% of the linear particles were less than 3 micrometers wide and more than 20 micrometers long. The authors put this at 10% to 15% of the aerosol particles. Citing earlier research by others, they said these sizes closely match fibers of asbestos, glass and aluminum oxide described as fibrogenic and carcinogenic. The study measured particles, not disease in people. The authors concluded that improper handling could be hazardous to dental personnel.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: laboratory particle characterization study: powders brushed onto slides and holders, and airborne dust collected after tumbling, examined by polarizing light microscopy, scanning electron microscopy and X-ray microanalysis; no people were studied
• Who was studied: two proprietary irreversible hydrocolloid (alginate) dental impression powders, Jeltrate (L. D. Caulk Co.) and Alginate (Coe Laboratories)
• Exposure: airborne particles released when alginate powder is tumbled in a closed can and the can is opened, collected at the can opening and 30 cm above it (the authors give 30 cm as the approximate distance of the mid-face during routine handling)
• Main results:
  • In powder applied by brush, about 40% of the particles were linear bodies
  • The linear particles were hollow tubules 1 to 5 micrometers in diameter and 10 to 100 micrometers long
  • Silicon was the predominant inorganic constituent of both powders
  • The Coe product contained a minor amount (less than 2%) of barium
  • In dust collected at the can opening, about 30% of the linear particles were less than 3 micrometers in diameter and more than 20 micrometers long
  • X-ray analysis of a single fiber from the dust showed a high silicon content (78.0%)
  • Dust collected 30 cm above the can was much less dense
  • At 30 cm, about 35% of the linear particles were less than 3 micrometers in diameter and more than 20 micrometers long
  • The authors stated that 10% to 15% of the aerosol particles collected 30 cm above the can were fibers less than 3 micrometers in diameter and more than 20 micrometers long
  • The authors said the siliceous particles had the petrographic features of diatomaceous earth
  • Citing earlier research by others, the authors said these fiber dimensions closely match those of fibrogenic and carcinogenic fibers of asbestos, glass and aluminum oxide
• The authors' conclusion: The authors concluded that, because alginate materials are used almost daily, improper handling could be hazardous to the health of dental personnel. They recommended that inhaling dust from the powders be avoided, and that the dust be treated as a potential hazard until further study shows otherwise.

Topics

Medical terms in this study, explained in our Lexicon: Fibrogenic, Carcinogenic.

Related studies

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• Relative source contributions of diet and air to ingested asbestos exposure — J.N. Rowe (1983)
• Evaluation of sensitivity of fluorescence-based asbestos detection by correlative microscopy — T. Ishida, M. Alexandrov, et al. (2012)
• Development of the Regular Interlaboratory Counting Exchanges (RICE) scheme to include visual reference counts and samples from asbestos clearance operations — P.W. Brown, N.P. Crawford, et al. (1994)

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