Sterilization kills everything, including bacterial spores. Disinfection kills most disease-causing organisms but not necessarily spores. That one word, spores, is the whole difference, and it decides how every item in the operatory gets processed.
Which items get which
The CDC sorts patient-care items by how they're used, and the category tells you the treatment:
- Critical items enter soft tissue or bone (surgical instruments, scalers, burs). Heat-sterilize, every time.
- Semicritical items touch mucous membranes or non-intact skin but don't penetrate (mirrors, impression trays, handpieces). Heat-sterilize if they can take it; high-level disinfect only if they can't.
- Noncritical items touch intact skin only (blood pressure cuff, x-ray tubehead, countertops). Clean and disinfect with an EPA-registered hospital disinfectant, or cover with a barrier.
Where people get tripped up
Handpieces are the classic one. They attach to air and water lines and touch the mouth, so they're semicritical, and the CDC says they should be heat-sterilized between patients. Wiping one down is not acceptable, no matter how thorough the wipe.
The other trap is thinking a disinfectant works on contact. It works for the contact time on the label, and the surface has to stay visibly wet that whole time. Spray, then immediately wipe dry, and you've cleaned the counter, not disinfected it.