Prophylaxis is not a vaccine. But it does significantly reduce the risk of recurrence of decay and periodontal disease.
It is generally accepted that a patient undergoing dental treatment or wearing fixed or removable partial dentures should undergo prophylaxis at least twice a year. During these sessions, we may need to do retro-alveolar radiological examinations, or even a panoramic examination to check the stability of the sub-bony parts invisible to the naked eye.