Dentures
Dentures are prosthetic devices constructed to replace missing teeth, supported by the surrounding soft and hard tissues of the oral cavity. Conventional dentures are removable. However, there are many denture designs, some of which rely on bonding or clasping onto teeth or dental implants. There are two main categories of dentures, the distinction being whether they fit onto the mandibular arch or on the maxillary arch.
Medical uses
Dentures can help people via:- Mastication: chewing ability is improved by the replacement of edentulous areas with denture teeth.
- Aesthetics: the presence of teeth gives a natural appearance to the face, and wearing a denture to replace missing teeth provides support for the lips and cheeks and corrects the collapsed appearance that results from the loss of teeth.
- Pronunciation: replacing missing teeth, especially the anteriors, enables patients to speak better, enunciating more easily sibilants and fricatives in particular.
- Self-esteem: improved looks and speech boost confidence in patients' ability to interact socially.
Complications
Stomatitis
Denture stomatitis is an inflammatory condition of the skin under the dentures. It can affect both partial and complete denture wearers, and is most commonly seen on the palatal mucosa. Clinically, it appears as simple localized inflammation, generalized erythema covering the denture-bearing area and inflammatory papillary hyperplasia. People with denture stomatitis are more likely to have angular cheilitis. Denture stomatitis is caused by a mixed infection of Candida albicans and a number of bacteria such as Staphylococcus, Streptococcus, Fusobacterium and Bacteroides species. Acrylic resin is more susceptible for fungal colonization, adherence and proliferation. In poor fitting dentures, these inflammations can be identified and referred to as a common sore of the mouth and are dependent on the severity of the inflammation.It's crucial to acknowledge that denture stomatitis ranks among the most prevalent conditions affecting denture wearers, affecting approximately 70% of this population. Early recognition of the signs and symptoms of denture stomatitis is vital for prompt treatment. Some of these symptoms include oral white or red patches, sore throat, pain or discomfort when swallowing, or sores in mouth. Common risk factors for denture stomatitis include denture trauma, poor denture hygiene and nocturnal denture wear. Additionally, systemic risk factors such as nutritional deficiencies, immunosuppression, smoking, diabetes, use of steroid inhalers, and xerostomia play a significant role. Therefore, it's important to conduct thorough examinations to detect any underlying systemic diseases.
Precautions denture wearers should take care improving the fit of ill-fitting dentures to eliminate any dental trauma. Stress on the importance of good denture hygiene including cleaning of the denture, soaking the dentures in disinfectant solution and not wearing it during sleeping at night is the key to treating all types of denture stomatitis. Topical application and systemic use of antifungal agents can be used to treat denture stomatitis cases that fail to respond to local conservative measures.
Ulceration
Mouth ulceration is the most common lesion in people with dentures. It can be caused by repetitive minor trauma like poorly fitting dentures including over-extension of a denture. Pressure-indicating paste can be used to check the fitting of dentures. It allows the areas of premature contact to be distinguished from areas of physiologic tissue contact. Therefore, the particular area can be polished with an acrylic bur. Leaching of residual monomer methyl methacrylate from inadequately cured denture acrylic resin material can cause mucosal irritation and hence oral ulceration as well. Patients are advised to use warm salt water mouth rinses and a betamethasone rinse which can heal such ulcers. Review of persisting oral ulcerations for more than 3 weeks is recommended.Tooth loss
People can become entirely edentulous for many reasons, the most prevalent being removal due to dental disease, which typically relates to oral flora control, i.e., periodontal disease and tooth decay. Other reasons include pregnancy, tooth developmental defects caused by severe malnutrition, genetic defects such as dentinogenesis imperfecta, trauma, or drug use.Periodontitis is defined as an inflammatory lesion mediated by host-pathogen interaction that results in the loss of connective tissue fiber attachment to the root surface and ultimately to the alveolar bone. It is the loss of connective tissue to the root surface that leads to teeth falling out. The hormones associated with pregnancy increases the risk of gingivitis and vomiting.
Hormones released during pregnancy softens the cardia muscle ring that keeps food within the stomach. Hydrochloric acid is the acid involved in gastric reflux, also known as morning sickness. This acid, at a pH of 1.5-3.5, coats the enamel on the teeth, mainly affecting the palatal surfaces of the maxillary teeth. Eventually the enamel is softened and easily wears away.
Dental trauma refers to trauma to the teeth and/or periodontium. Strong force may cause the root of the tooth to completely dislocate from its socket, mild trauma may cause the tooth to chip.
Types
Removable partial dentures
s are for patients who are missing some of their teeth on a particular arch. Fixed partial dentures, also known as "crown and bridge" dentures, are made from crowns that are fitted on the remaining teeth. They act as abutments and pontics, and are made from materials resembling the missing teeth. Fixed bridges are more expensive than removable appliances but are more stable.Another option in this category is the flexible partial, which takes advantage of innovations in digital technology. Flexible partial fabrication involves only non-invasive procedures. Dentures can be difficult to clean and can affect oral hygiene.
Complete dentures
are worn by patients who are missing all of the teeth in a single arch—i.e. the maxillary or mandibular arch—or, more commonly, in both arches. The full denture is removable because it is held in place by suction. They are painful at first and can take some time to get used to. There are two types of full dentures: immediate dentures and conventional dentures.Copy dentures
Copy dentures can be made for either partial, but mainly complete denture patients. These dentures require fewer visits to make and usually are made for older patients, patients who would have difficulty adjusting to new dentures, would like a spare pair of dentures or like the aesthetics of their dentures already. This requires taking an impression of the patient's current denture and remaking it.Materials
Dentures are mainly made from acrylic due to the ease of material manipulation and likeness to intra-oral tissues, i.e. gums. Most dentures are composed of heat-cured acrylic polymethyl methacrylate and rubber-reinforced polymethyl methacrylate. Coloring agents and synthetic fibers are added to obtain the tissue-like shade, and to mimic the small capillaries of the oral mucosa, respectively. However, dentures made from acrylic can be fragile and fracture easily if the patient has trouble adapting neuromuscular control. This can be overcome by reinforcing the denture base with cobalt chromium. They are often thinner and stronger.History
As early as the 7th century BC, Etruscans in northern Italy made partial dentures out of human or other animal teeth fastened together with gold bands. The Romans had likely borrowed this technique by the 5th century BC. A text by Martial referenced Cascellius, who extracted or repaired painful teeth. H. L. Strömgren, postulated that by repairing it was meant tooth replacement and not tooth filling.Wooden full dentures were invented in Japan around the early 16th century. Softened beeswax was inserted into the patient's mouth to create an impression, which was then filled with harder bees wax. Wooden dentures were then meticulously carved based on that model. The earliest of these dentures were entirely wooden, but later versions used natural human teeth or sculpted pagodite, ivory, or animal horn for the teeth. These dentures were built with a broad base, exploiting the principles of adhesion to stay in place. This was an advanced technique for the era; it was not replicated in the West until the late 18th century. Wooden dentures continued to be used in Japan until the Opening of Japan to the West in the 19th century.
In 1728, Pierre Fauchard described the construction of dentures using a metal frame and teeth sculpted from animal bone. The first porcelain dentures were made around 1770 by Alexis Duchâteau. In 1791, the first British patent was granted to Nicholas Dubois De Chemant, previous assistant to Duchateau, for "De Chemant's Specification":
He began selling his wares in 1792, with most of his porcelain paste supplied by Wedgwood.
17th century London's Peter de la Roche is believed to be one of the first 'operators for the teeth', men who advertized themselves as specialists in dental work. They were often professional goldsmiths, ivory turners or students of barber-surgeons.
In 1820, Samuel Stockton, a goldsmith by trade, began manufacturing high-quality porcelain dentures mounted on 18-carat gold plates. Later dentures from the 1850s onwards were made of Vulcanite, a form of hardened rubber into which porcelain teeth were set. In the 20th century, acrylic resin and other plastics were used. In Britain, sequential Adult Dental Health Surveys revealed that in 1968 79% of those aged 65–74 had no natural teeth; by 1998, this proportion had fallen to 36%.