Prophylaxis helps prevent periodontal disease. The appointment includes medical history screening, yes there are medical reasons some cannot have a prophy that day. Dental assistants can’t screen medical histories. We screen for periodontal diseases. This includes measuring and recording 6 areas around every tooth, including implants. Those numbers then are interpreted and the patient is classified. This is impossible to teach on the job. We are often the first healthcare professionals to see signs of an eating disorder. One of the deadliest of all the mental illnesses. You can’t teach that on the job.  We chart the entire mouth of restorations, which can include work that was done 80 years ago. Home care instructions are the most important part of the appointment. Actual scaling is only one part of the visit. Getting your teeth cleaned properly means scaling under the gums to help prevent periodontal disease. There’s no point in scaling above the gum line other than aesthetics