Dentistry

Dentistry is the branch of medicine that is involved in the study, diagnosis, prevention, and treatment of diseases, disorders and conditions of the oral cavity, the maxillofacial area and the adjacent and associated structures, and their impact on the human body.[1] To the layman, dentistry tends to be perceived as being focused primarily on human teeth, though it is not limited strictly to this. Dentistry is widely considered necessary for complete overall health. Doctors who practice dentistry are known as dentists. The dentist's supporting team – which includes dental assistants, dental hygienists, dental technicians, and dental therapists – aids in providing oral health services.

Overview
Sagittal section of a toothDental surgery and treatments[edit]Dentistry usually encompasses very important practices related to the oral cavity. Oral diseases are major public health problems due to their high incidence and prevalence across the globe with the disadvantaged affected more than other socio-economic groups.[2]

The majority of dental treatments are carried out to prevent or treat the two most common oral diseases which are dental caries (tooth decay) and periodontal disease (gum disease or pyorrhea). Common treatments involve the restoration of teeth, extraction or surgical removal of teeth, scaling and root planing and endodontic root canal treatment.

All dentists in the United States undergo at least three years of undergraduate studies, but nearly all complete a bachelors degree. This schooling is followed by four years of dental school to qualify as a "Doctor of Dental Surgery" (DDS) or "Doctor of Dental Medicine" (DMD). Dentists need to complete additional qualifications or continuing education to carry out more complex treatments such as sedation, oral and maxillofacial surgery, and dental implants.

By nature of their general training they can carry out the majority of dental treatments such as restorative (fillings, crowns, bridges), prosthetic (dentures), endodontic (root canal) therapy, periodontal (gum) therapy, and extraction of teeth, as well as performing examinations, radiographs (x-rays) and diagnosis. Dentists can also prescribe medications such as antibiotics, sedatives, and any other drugs used in patient management.

Prevention[edit]Dentists also encourage prevention of oral diseases through proper hygiene and regular, twice yearly, checkups for professional cleaning and evaluation. Conditions in the oral cavity may be indicative of systemic diseases such as osteoporosis, diabetes, or cancer. Many studies have also shown that gum disease is associated with an increased risk of diabetes, heart disease, and preterm birth.

Education and licensing
Early dental chair in Pioneer West Museum in Shamrock, TexasDr. John M. 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 1828, and today is a dental museum.[3] The first dental college, Baltimore College of Dental Surgery, opened in Baltimore, Maryland, USA in 1840. Philadelphia Dental College was founded in 1863 and is the second in the United States. In 1907 Temple University accepted a bid to incorporate the school.

Studies showed that dentists graduated from different countries,[4] or even from different dental schools in one country,[5] may have different clinical decisions for the same clinical condition. For example, dentists graduated from Israeli dental schools may recommend more often for the removal of asymptomatic impacted third molar (wisdom teeth) than dentists graduated from Latin American or Eastern European dental schools.[6]

In the United Kingdom, the 1878 British Dentists Act and 1879 Dentists Register limited the title of "dentist" and "dental surgeon" to qualified and registered practitioners.[7][8] However, others could legally describe themselves as "dental experts" or "dental consultants".[9] The practice of dentistry in the United Kingdom became fully regulated with the 1921 Dentists Act, which required the registration of anyone practicing dentistry.[10] The British Dental Association, formed in 1880 with Sir John Tomes as president, played a major role in prosecuting dentists practising illegally.[7]

There are sixteen dental schools in the UK, five of which are graduate entry programmes, only admitting applicants with at least an upper 2.1 in a classified undergraduate degree with a significant component of biomedical sciences. Thus the competition for places is fierce (approximately 1 successful candidate admitted in every 26 applicants in 2013).[11][12] Because of the low numbers of dental schools, funding for building and service developments in the schools can be very high. Well known UK universities providing dental courses are the Universities of Leeds, Liverpool, Glasgow, Cardiff, Queen's Belfast, Birmingham, Bristol, Dundee, Manchester, Sheffield and King's College London.[13] As of 2013, the only UK universities offering a 4-year graduate-entry BDS programme are Liverpool, King's College London, BLSMD, UCLan and Aberdeen.

In Korea, Taiwan, Japan, Finland, Sweden, Brazil, Chile, the United States, and Canada, a dentist is a healthcare professional qualified to practice dentistry after graduating with a degree of either Doctor of Dental Surgery (DDS) or Doctor of Dental Medicine (DMD). This is equivalent to the Bachelor of Dental Surgery/Baccalaureus Dentalis Chirurgiae (BDS, BDent, BChD, BDSc) that is awarded in the UK and British Commonwealth countries. In most western countries, to become a qualified dentist one must usually complete at least four years of postgraduate study[citation needed]; 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.

Specialties 
A dentist in Finland treating a childMain article: Specialty (dentistry)
The American Dental Association recognizes nine dental specialties: dental public health, endodontics, oral and maxillofacial pathology, oral and maxillofacial radiology, oral and maxillofacial surgery, orthodontics, pediatric dentistry, periodontics, and prosthodontics.[14] There are other dental niches such as oral medicine, dental aesthetics, dental implantation, dental anesthesiology, and orofacial pain and temporomandibular disorders; some of them are recognized as dental specialties in other countries. In the European Union all member states must recognize the specialties of orthodontics and oral and maxillofacial surgery.

History
Farmer at the dentist, Johann Liss, c. 1616–17.The Indus Valley Civilization (IVC) has yielded evidence of dentistry being practised as far back as 7000 BC.[15] An IVC site in Mehrgarh indicates that this earliest form of dentistry involved curing tooth related disorders with bow drills operated, perhaps, by skilled bead craftsmen.[16] The reconstruction of this ancient form of dentistry showed that the methods used were reliable and effective.[17] The earliest dental filling, made of beeswax, was discovered in Slovenia and dates from 6500 years ago.[18]

A Sumerian text from 5000 BC describes a "tooth worm" as the cause of dental caries.[19] Evidence of this belief has also been found in ancient India, Egypt, Japan, and China. The legend of the worm is also found in the writings of Homer, and as late as the 14th century AD the surgeon Guy de Chauliac still promoted the belief that worms cause tooth decay.[20]

The Edwin Smith Papyrus, written in the 17th century BC but which may reflect previous manuscripts from as early as 3000 BC, includes the treatment of several dental ailments.[21][22] In the 18th century BC, the Code of Hammurabi referenced dental extraction twice as it related to punishment.[23] Examination of the remains of some ancient Egyptians and Greco-Romans reveals early attempts at dental prosthetics and surgery.[24]

Ancient Greek scholars Hippocrates and Aristotle wrote about dentistry, including the eruption pattern of teeth, treating decayed teeth and gum disease, extracting teeth with forceps, and using wires to stabilize loose teeth and fractured jaws.[25] Some say the first use of dental appliances or bridges comes from the Etruscans from as early as 700 BC.[26] In ancient Egypt, Hesi-Re is the first named "dentist" (greatest of the teeth). 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.[27][28] The earliest dental amalgams were first documented in a Tang Dynasty medical text written by the Chinese physician Su Kung in 659, and appeared in Germany in 1528.[29][30]

Historically, dental extractions have been used to treat a variety of illnesses. 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[31] (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[31] which, in turn, was replaced by modern forceps in the 20th century.[citation needed]

The first book focused solely on dentistry was the "Artzney Buchlein" in 1530,[32] and the first dental textbook written in English was called "Operator for the Teeth" by Charles Allen in 1685.[8]

Modern dentistry
Dental needle-nose pliers designed by Fauchard in the late 17th century to use in prosthodontics.It was between 1650 and 1800 that the science of modern dentistry developed. The English physician Thomas Browne in his A Letter to a Friend (pub. post. 1690) made an early dental observation with characteristic humour –

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: and therefore in Egypt, where one Man practised but one Operation, or the Diseases but of single Parts, it must needs be a barren Profession to confine unto that of drawing of Teeth, and little better than to have been Tooth-drawer unto King Pyrrhus, who had but two in his Head.

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 watch makers, 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, in the gums, could appear in the later stages of tooth decay.[33][34]

Fauchard was the pioneer of dental prosthesis, and he discovered many methods to replace lost teeth. 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 1723 publication Le chirurgien dentiste or The Surgeon Dentist. The French text included “included basic oral anatomy and function, dental construction, and various operative and restorative techniques, and effectively separated dentistry from the wider category of surgery”.[33][34]

 
A modern Dentist's chair.After Fauchard, the study of dentistry rapidly expanded. Two important books, Natural History of Human Teeth (1771 ) and Practical Treatise on the Diseases of the Teeth (1778), were published by British surgeon John Hunter. In 1763 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.[35] The profession came under government regulation by the end of the 19th century.

Priority patients[edit]UK NHS priority patients include patients with congenital abnormalities (such as cleft palates and hypodontia), patients who have suffered orofacial trauma and those being treated for cancer in the head and neck region. These are treated in a multidisciplinary team approach with other hospital based dental specialities orthodontics and maxillofacial surgery. Other priority patients include those with infections (either third molars or necrotic teeth) or avulsed permanent teeth, as well as patients with a history of smoking or smokeless tobacco with ulcers in the oral cavity also.