Which of the following dental items is classified as a SEMI-CRITICAL item requiring high-level disinfection or sterilization?

Using Spaulding's classification for medical devices: Critical items (contact bone, blood, sterile tissue — must be sterilized): scalpels, needles, burs, forceps, scalers. Semi-critical items (contact mucous membranes or non-intact skin but do not penetrate — require high-level disinfection or sterilization): dental mirrors, impression trays, intraoral radiographic sensors, amalgam condensers. Non-critical items (contact intact skin only — require low-level disinfection): blood pressure cuffs, x-ray tube heads, light handles. A digital sensor contacts mucous membranes but does not penetrate tissue, making it semi-critical. Needles and scalpels penetrate tissue and are critical items. Cotton rolls contact intact mucosa and are non-critical (single-use items).