Background
Several of the components in the modern acrylate based dental materials are known to be skin irritants and contact sensitizers. To avoid dermatitis it is important to reduce skin exposure to these chemicals. One first step to this is to identify where and during which moments of work the exposure takes place. Secondly it is important to have knowledge about the protective effect of gloves available on the market.

Aim
The aims of the study were
1) to identify where and when skin contamination with dental material takes place during work and
2) to find out to what extent acrylates permeate gloves.

Methods
The first part was studied by mixing a fluorochrome in commercially available dental bonding materials. Ordinary dental work of treating two cavities with bonding was simulated on training dolls. The work was filmed on video. The contamination was visualized by exposing the hands, arms, face and equipment to UV-light and fluorescence was documented with photography before and after work.

The second part was studied by testing permeation through glove materials according to a standardized method. Gloves tested were made of natural rubber latex (NRL), nitril rubber (NR), polyethylene-copolymer (PEC) and polyvinyl chloride (PVC).

A glove membrane was mounted in a two compartment permeation cell and exposed to water ethanol and acetone solutions of methyl methacrylate (MMA), hydroxyethyl methacrylate (HEMA) and tetraetyleneglycol dimethacrylate (TEGDMA). Analysis of permeated acrylates was done using a gas chromatograph with an in-line gas-sampling valve or by manual sampling.

Results
Fluorescence could be found on 25 of 34 exposed persons. The heaviest contamination was found on the fingers and on the bottles with dental material on unassisted dentists and assisting dental nurses. Some contamination was located to the hands and, in a few cases, the arms were contaminated. Some spread to working tools could be seen. Work technique strongly influenced the contamination pattern. Using a dappen dish instead of dripping direct on Quick sticks gave more extended contamination.

The glove materials studied were all permeable to acrylate monomers. The highest permeation rates were found for MMA. Of the gloves tested, a methylethylacrylate co-polymer and a thick natural rubber latex glove showed the best protective effect. There was a higher penetration rate from an acetone solution compared to an ethanol or water solution of the same concentration.

Conclusion
Using a cautious working technique, long sleeve shirt and proper protective gloves reduces the risk of skin contamination with allergenic and irritant dental materials. Video documentation of the work process was a very helpful tool in the analysis of the results. The different solvents the acrylates were dissolved in influenced the penetration rate through the protective gloves.