Harris started the world's first dental school in Bainbridge, Ohio , and helped to establish dentistry as a health profession. It opened on 21 February , and today is a dental museum. Studies show that dentists that graduated from different countries,  or even from different dental schools in one country,  may make different clinical decisions for the same clinical condition.
For example, dentists that graduated from Israeli dental schools may recommend the removal of asymptomatic impacted third molar wisdom teeth more often than dentists that graduated from Latin American or Eastern European dental schools. In most western countries, to become a qualified dentist one must usually complete at least four years of postgraduate study;  within the European Union the education has to be at least five years.
Dentists usually complete between five and eight years of post-secondary education before practising. Though not mandatory, many dentists choose to complete an internship or residency focusing on specific aspects of dental care after they have received their dental degree. Specialty dentistry Some dentists undertake further training after their initial degree in order to specialize.
Exactly which subjects are recognized by dental registration bodies varies according to location. Dental public health — The study of epidemiology and social health policies relevant to oral health. Conservative dentistry and endodontics: The art and science of restoring the tooth form and function when destructed by carious and non carious lesions affecting the teeth, before involvement of pulp or root canal is termed as conservative dentistry.
When the root canal are involved, the speciality is known as endodontics. This speciality degree is awarded in India. Endodontics also called endodontology — Root canal therapy and study of diseases of the dental pulp and periapical tissues. Forensic odontology — The gathering and use of dental evidence in law. This may be performed by any dentist with experience or training in this field.
The function of the forensic dentist is primarily documentation and verification of identity. Geriatric dentistry or Geriodontics — The delivery of dental care to older adults involving the diagnosis, prevention, and treatment of problems associated with normal aging and age-related diseases as part of an interdisciplinary team with other health care professionals. Oral and maxillofacial pathology — The study, diagnosis, and sometimes the treatment of oral and maxillofacial related diseases.
Oral and maxillofacial radiology — The study and radiologic interpretation of oral and maxillofacial diseases. Oral and maxillofacial surgery also called oral surgery — Extractions , implants , and surgery of the jaws, mouth and face. Oral medicine — The clinical evaluation and diagnosis of oral mucosal diseases Orthodontics and dentofacial orthopedics — The straightening of teeth and modification of midface and mandibular growth.
Pediatric dentistry also called pedodontics — Dentistry for children Periodontology also called periodontics — The study and treatment of diseases of the periodontium non-surgical and surgical as well as placement and maintenance of dental implants Prosthodontics also called prosthetic dentistry — Dentures , bridges and the restoration of implants.
Some prosthodontists further their training in "oral and maxillofacial prosthodontics", which is the discipline concerned with the replacement of missing facial structures, such as ears, eyes, noses, etc.
Special needs dentistry also called special care dentistry — Dentistry for those with developmental and acquired disabilities. Veterinary dentistry , a speciality of veterinary medicine — The field of dentistry applied to the care of animals.
Farmer at the dentist, Johann Liss , c. The legend of the worm is also found in the writings of Homer [ where? The Egyptians bound replacement teeth together with gold wire. Roman medical writer Cornelius Celsus wrote extensively of oral diseases as well as dental treatments such as narcotic-containing emollients and astringents.
During the Middle Ages and throughout the 19th century, dentistry was not a profession in itself, and often dental procedures were performed by barbers or general physicians. Barbers usually limited their practice to extracting teeth which alleviated pain and associated chronic tooth infection. Instruments used for dental extractions date back several centuries. In the 14th century, Guy de Chauliac invented the dental pelican  resembling a pelican 's beak which was used to perform dental extractions up until the late 18th century.
The pelican was replaced by the dental key  which, in turn, was replaced by modern forceps in the 20th century. The Royal Commission on the National Health Service in reported that there were then more than twice as many registered dentists per 10, population in the UK than there were in The Egyptian Mummies that I have seen, have had their Mouths open, and somewhat gaping, which affordeth a good opportunity to view and observe their Teeth, wherein 'tis not easie to find any wanting or decayed: The French surgeon Pierre Fauchard became known as the "father of modern dentistry".
Despite the limitations of the primitive surgical instruments during the late 17th and early 18th century, Fauchard was a highly skilled surgeon who made remarkable improvisations of dental instruments, often adapting tools from watchmakers , jewelers and even barbers , that he thought could be used in dentistry. He introduced dental fillings as treatment for dental cavities.
He asserted that sugar derivate acids like tartaric acid were responsible for dental decay , and also suggested that tumors surrounding the teeth and in the gums could appear in the later stages of tooth decay. He suggested that substitutes could be made from carved blocks of ivory or bone. He also introduced dental braces , although they were initially made of gold, he discovered that the teeth position could be corrected as the teeth would follow the pattern of the wires.
Waxed linen or silk threads were usually employed to fasten the braces. His contributions to the world of dental science consist primarily of his publication Le chirurgien dentiste or The Surgeon Dentist.
The French text included "basic oral anatomy and function, dental construction, and various operative and restorative techniques, and effectively separated dentistry from the wider category of surgery". In he entered into a period of collaboration with the London-based dentist James Spence. He began to theorise about the possibility of tooth transplants from one person to another. He realised that the chances of an initially, at least successful tooth transplant would be improved if the donor tooth was as fresh as possible and was matched for size with the recipient.
These principles are still used in the transplantation of internal organs. Hunter conducted a series of pioneering operations, in which he attempted a tooth transplant.
Although the donated teeth never properly bonded with the recipients' gums, one of Hunter's patients stated that he had three which lasted for six years, a remarkable achievement for the period. The profession came under government regulation by the end of the 19th century. In the same year, Francis Brodie Imlach was the first ever dentist to be elected President of the Royal College of Surgeons Edinburgh , raising dentistry onto a par with clinical surgery for the first time.
Occupational hazards in dentistry Long term occupational noise exposure can contribute to permanent hearing loss, which is referred to as noise-induced hearing loss NIHL and tinnitus. Noise exposure can cause excessive stimulation of the hearing mechanism, which damages the delicate structures of the inner ear.
Regulations state that the permissible noise exposure levels for individuals is 90 dBA. Exposures below 85 dBA are not considered to be hazardous. Time limits are placed on how long an individual can stay in an environment above 85 dBA before it causes hearing loss.
The exposure time becomes shorter as the dBA level increases. Within the field of dentistry, a variety of cleaning tools are used including piezoelectric and sonic scalers, and ultrasonic scalers and cleaners.