Preventative dentistry is a subdivision of dentistry that focuses on preventing certain conditions from occurring. A person may visit a local dentist and request preventative dentistry services for a wide variety of reasons. The most common reason that a person would ask for such a service is to prevent the development of cavities. Dental sealants can help to place a layer of protection on the teeth so that the dental patient does not develop cavities. A cosmetic dentist is a specialist that can perform the procedure for the person.