Field and Laboratory Measurements Related to Occupational and Consumer Exposures - Safety of Nanomaterials along Their Lifecycle - page 301

van Landuyt
et al. (2012)

Polishing,
grinding

Silica from
dental
composites

Yes, single
nano-iller
particles
frequently
observed

MC Polymerized blocks of contemporary composites (Nano-Filler

54-70% total volume) were ground with a diamond bur
according to a clinically relevant protocol. All composites
released respirable dust in experimental setting. These
observations were corroborated by the clinical measurements;
however only short episodes of high concentrations of
respirable dust upon polishing composites could be observed.
Electron microscopic analysis showed that the size of the dust
varied widely with particles larger than 10 µm, but submicron
and even nano-sized particles could also be observed. The dust
particles often consisted of multiple iller particles contained in
resin, but single nano-iller particles could also frequently be
distinguished

van Landuyt
et al. (2013)

Grinding Commercial

dental
composites

SEM/TEM/EDX PSD (SMPS) Exposure measurements of dust in a dental clinic revealed high

peak concentrations of nanoparticles in the breathing zone of
both dentist and patient, especially during aesthetic treatments
or treatments of worn teeth with composite build-ups. Further
laboratory assessment conirmed that all tested composites
released very high concentrations of airborne particles in the
nano-range (>10 6 #/cm 3 ). The median diameter of composite
dust varied between 38 and 70 nm. Electron microscopic and
energy dispersive X-ray analysis conirmed that the airborne
particles originated from the composite, and revealed that the
dust particles consisted of either iller particles, resin, or both
( Continued )