What is the difference in a dental assistant and dental hygienist?

Here are some differences.

First, their responsibilities: Dental assistants are responsible for assisting the dentist in whatever procedure he/she may be doing. This includes preparing the room and the patient, setting up whatever instruments and supplies will be needed, exposing any necessary x-rays, etc. Assistants also take many dental impressions and make temporary restorations that the patient will wear until the permanent restorations are ready. Assistants also provide a second (and sometimes a third) set of hands during dental procedures. Assistants use air, water, and suction to keep the surgical fields clear, they pass instruments to the dentist, they retract tissue, and they do whatever else is necessary to allow the dentist to provide the best possible care to the patient. Often, the assistant will answer any patient questions and give the patient post-operative instructions.

Hygienists are primarily responsible for providing preventive dental services (dental cleanings, fluoride treatments, etc.) and non-surgical treatment of gum disease, usually at the direction of the dentist. Hygienists remove tartar and plaque from below the gum line with a combination of hand and power instruments. Hygienists are often the primary source of patients' dental education in the office.

A second difference is their respective levels of education. In most jurisdictions, dental assistants legally require no formal education beyond on-the-job training. Some states require some formal training through accredited courses to provide some advanced services.

All states require dental hygienists to be licensed. This means they have at least an undergraduate degree from an accredited school of dental hygiene, have passed a national written exam, and demonstrated some degree of clinical competence. Most states allow dental hygienists to administer local anesthetics and nitrous oxide sedation provided they have the proper training.

Because of their higher education requirements and their licensure, dental hygienists generally command a higher salary than dental assistants.