Which of the following is NOT a critical instrument?

Infection control practices categorize instruments based on the risk of transmitting infection. Critical instruments are those that penetrate soft tissue or bone and, therefore, have a high risk of carrying pathogens, necessitating thorough sterilization. The dental x-ray tubehead is not classified as a critical instrument because it does not come into direct contact with mucous membranes or have the potential to penetrate tissue. Instead, it generates the x-ray images through a non-contact process and is exposed to less risk in terms of infection transmission.

In contrast, instruments like bone chisels, scalpels, and forceps are classified as critical instruments because they directly interact with tissues and have the potential to cause significant exposure to microorganisms. Consequently, they require sterilization between uses to ensure patient safety. The differentiation between critical instruments and others is crucial in implementing appropriate infection control protocols in dental settings.