Comparative life cycle assessment of reused versus disposable dental burs

Purpose: Health care infection control has led to increased utilization of disposable medical devices, which has subsequently led to adverse environmental effects attributed to health care and its supply chain. In dental practice, the dental bur is a commonly used instrument that can be either reused or used once and then disposed. To evaluate the disparities in environmental impacts of disposable and reusable dental burs, a comparative life cycle assessment (LCA) was performed. Methods: The functional unit was defined as one reusable dental bur, where the maximum instances reused was 30 (or in the case of a disposable, the equivalent functional unit would be 30 disposable dental burs). The system boundary included all cradle-to-grave aspects of both single-use and reused burs, including raw material extraction, manufacturing, packaging, distribution, reuse, and disposal. Primary data included the following: operating parameters for ultrasonic cleaning, manual cleaning, and autoclaving of the burs. The secondary data for raw material extraction and production of dental bur and packaging were obtained directly from life cycle inventory databases. Sensitivity analyses were also performed with respect to ultrasonic and autoclave loading. Results and discussion: Findings from this research showed that when the ultrasonic and autoclave were loaded optimally, reusable burs had 40 % less of an environmental impact than burs used on a disposable basis. When the autoclave and ultrasonic were loaded to approximately two-third capacity, four environmental impact categories favored reusable burs (i.e., ozone depletion, smog, respiratory effects, exotoxicity), and four impact categories environmentally favored disposables (i.e., acidification, eutrophication, carcinogenics, and non-carcinogenics). When the autoclave and ultrasonic were loaded to approximately one-third capacity, reusable dental burs posed more negative environmental impacts in eight of nine environmental impact categories when compared to disposable burs. Conclusions: Operational efficiency of ultrasonic and autoclave cleaning equipment should be emphasized to enhance the environmental performance of bur reuse. In fact, improper loading of the ultrasonic and autoclave can lead to greater adverse environmental impacts than if the burs were treated as disposables. The environmental and economic impacts associated with bur reuse are expected to be similar with other dental devices that are designated as disposable but are capable of being reused (e.g., scalpels, forceps).