A dental hygienist works closely with dentists and is mainly responsible for performing dental cleanings. They ensure patients are comfortable and prepared for their appointments, sterilize dental equipment, check for signs of cavities and gingivitis, remove excess plaque and tartar from teeth, and apply preventative sealants like fluoride. Additional duties may include taking dental impressions, operating x-ray machines, and working with dentists to determine diagnoses, and keeping up-to-date documentation of patient visits. Dental hygienists work in a dental office.