Quantitative and qualitative analysis of operator inhaled aerosols during routine motorised equine dental treatment.

Abstract

Routine equine odontoplasty is performed by both Veterinary Surgeons and Equine Dental Technicians. The production of aerosolised particulates from motorised equipment has been well documented in human orthodontics but has yet to be investigated in the veterinary industry. To assess the size, quantity and composition of particulates produced during routine motorised odontoplasty and to model their deposition in the human respiratory tree. Analytic observational study. Fifteen-minute routine motorised odontoplasties were performed on cadaver heads with monitoring equipment placed 30cm away from the oral cavity to simulate the position of the operator's face. For quantitative analysis, an active air sampling photometric monitor was used to detect the concentration of fully respirable (<4.25µm) particles produced. The use of water and non-water-cooled equipment and 2 different types of face mask (standard surgical and FFP3) were compared. An 8-stage Marple Personal Cascade Impactor modelled the deposition of the particulates in relation to the human respiratory tree. Qualitative analysis of these particulates was performed using scanning electron microscopy and energy dispersive x-ray spectroscopy. Motorised odontoplasty created aerosolised particulates that could reach all levels of the human respiratory tree. These particulates were composed mostly of calcium and phosphate, although traces of metals were found. The concentration of fully respirable particulates exceeded the recommended exposure limits set by the Health and Safety Executive. The use of an FFP-3 face mask significantly reduced the level of inhaled particulates. This was a simulated experiment. It does not take into account the variety of environments in which routine treatment takes place. There are possible health risks in performing a large amount of routine motorised dentistry due to inhalation of aerosolised particulates. The use of an adequate face mask lowers exposure levels to within acceptable limits and, therefore, should be worn.