| Streptococcus sobrinus | |
|---|---|
Scientific classification  | |
| Domain: | Bacteria |
| Phylum: | Bacillota |
| Class: | Bacilli |
| Order: | Lactobacillales |
| Family: | Streptococcaceae |
| Genus: | Streptococcus |
| Species: | S. sobrinus |
| Binomial name | |
| Streptococcus sobrinus (ex Coykendall 1974) Coykendall 1983 | |
Streptococcus sobrinus is a Gram-positive, catalase-negative, non-motile, and anaerobic member of the genus Streptococcus . [1]
Streptococcus sobrinus in conjunction with the closely related species Streptococcus mutans are pathogenic within humans and enhances the formation of caries within teeth. Biofilm from the mixture of sugar and plaque create a suitable environment for S. sobrinus to grow. S. sobrinus is more closely connected with the prevalence of caries than S. mutans.[ citation needed ]S. sobrinus is also affiliated with early childhood caries, which are responsible for the majority of dental abscesses and toothaches in children. Children generally acquire S. sobrinus strains from their mother, but the relatively high consumption of sugars by minors facilitates bacterial growth and threatens the onset of early childhood tooth decay. S. sobrinus has also been documented within the teeth of rats.[ citation needed ]
Streptococcus sobrinus was discovered by the French biologist Louis Pasteur in 1887 along with other human pathogens. The full genome of S. sobrinus has been sequenced, [2] and the related species S. mutans has also been fully sequenced.
Extracellular long-chained glucans synthesized from sucrose via glucosyltransferase enzymes help accumulate S. sobrinus on tooth enamel surfaces. The glucans provide a shelter for bacterial colonization, and the protected environment creates the perfect nesting ground for S. sobrinus and other microorganisms to sustain a stable community in the form of dental plaque. S. sobrinus in turn releases lactic acid in the anaerobic metabolism of glucose. Lactic acid demineralizes tooth enamel and fosters the initiation of dental caries. S. sobrinus has an optimal growth temperature of 37 °C and thrives in a slightly acidic environment at a pH of 6.3. This makes the human mouth a suitable habitat due to its acidic characteristics, favorable body temperature, and significant amount of food sugars passing through the mouth on a daily basis. However, these traits also indicate that S. sobrinus has a difficult time surviving outside the host of the human teeth.[ citation needed ]
In 1995 a paper by Meurman et al. tested Lactobacillus rhamnosus for inhibitory properties, although this relationship was only observed with a weak correlation at a pH below 5. Lectin from Talisia esculenta and Labramin from Labramia bojeri seeds were found to inhibit the adherence of S. sobrinus to tooth enamel, but had no effect on the growth of the population itself. A study by Sun et al. in 2009, tested a vaccine for S. sobrinus, and initial tests have been successful in providing protection.[ citation needed ]
Human teeth function to mechanically break down items of food by cutting and crushing them in preparation for swallowing and digesting. As such, they are considered part of the human digestive system. Humans have four types of teeth: incisors, canines, premolars, and molars, which each have a specific function. The incisors cut the food, the canines tear the food and the molars and premolars crush the food. The roots of teeth are embedded in the maxilla or the mandible and are covered by gums. Teeth are made of multiple tissues of varying density and hardness.
Xylitol is a chemical compound with the formula C
5H
12O
5, or HO(CH2)(CHOH)3(CH2)OH; specifically, one particular stereoisomer with that structural formula. It is a colorless or white crystalline solid that is freely soluble in water. It can be classified as a polyalcohol and a sugar alcohol, specifically an alditol. The name derives from Ancient Greek: ξύλον, xyl[on] 'wood', with the suffix -itol used to denote sugar alcohols.
Tooth enamel is one of the four major tissues that make up the tooth in humans and many other animals, including some species of fish. It makes up the normally visible part of the tooth, covering the crown. The other major tissues are dentin, cementum, and dental pulp. It is a very hard, white to off-white, highly mineralised substance that acts as a barrier to protect the tooth but can become susceptible to degradation, especially by acids from food and drink. Calcium hardens the tooth enamel. In rare circumstances enamel fails to form, leaving the underlying dentin exposed on the surface.
Tooth decay, also known as cavities or caries, is the breakdown of teeth due to acids produced by bacteria. The cavities may be a number of different colors from yellow to black. Symptoms may include pain and difficulty with eating. Complications may include inflammation of the tissue around the tooth, tooth loss and infection or abscess formation.
Dental sealants are a dental treatment intended to prevent tooth decay. Teeth have recesses on their biting surfaces; the back teeth have fissures (grooves) and some front teeth have cingulum pits. It is these pits and fissures that are most vulnerable to tooth decay because food and bacteria stick in them and because they are hard-to-clean areas. Dental sealants are materials placed in these pits and fissures to fill them in, creating a smooth surface which is easy to clean. Dental sealants are mainly used in children who are at higher risk of tooth decay, and are usually placed as soon as the adult molar teeth come through.
Streptococcus mutans is a facultatively anaerobic, gram-positive coccus commonly found in the human oral cavity and is a significant contributor to tooth decay. It is part of the "streptococci", an informal general name for all species in the genus Streptococcus. The microbe was first described by James Kilian Clarke in 1924.
Dental plaque is a biofilm of microorganisms that grows on surfaces within the mouth. It is a sticky colorless deposit at first, but when it forms tartar, it is often brown or pale yellow. It is commonly found between the teeth, on the front of teeth, behind teeth, on chewing surfaces, along the gumline (supragingival), or below the gumline cervical margins (subgingival). Dental plaque is also known as microbial plaque, oral biofilm, dental biofilm, dental plaque biofilm or bacterial plaque biofilm. Bacterial plaque is one of the major causes for dental decay and gum disease.
The dental pellicle, or acquired pellicle, is a protein film that forms on the surface enamel, dentin, artificial crowns, and bridges by selective binding of glycoproteins from saliva that prevents continuous deposition of salivary calcium phosphate. It forms in seconds after a tooth is cleaned, or after chewing. It protects the tooth from the acids produced by oral microorganisms after consuming carbohydrates.
Early childhood caries (ECC), formerly known as nursing bottle caries, baby bottle tooth decay, night bottle mouth and night bottle caries, is a disease that affects teeth in children aged between birth and 71 months. ECC is characterized by the presence of 1 or more decayed, missing, or filled tooth surfaces in any primary tooth. ECC has been shown to be a very common, transmissible bacterial infection, usually passed from the primary caregiver to the child. The main bacteria responsible for dental caries are Streptococcus mutans and Lactobacillus. There is also evidence that supports that those who are in lower socioeconomic populations are at greater risk of developing ECC.
A caries vaccine is a vaccine to prevent and protect against tooth decay. Streptococcus mutans has been identified as the major etiological agent of human dental caries. The development of a vaccine for tooth decay has been under investigation since the 1970s. In 1972, a caries vaccine was said to be in animal testing in England, and that it would have begun human testing soon. However, intrinsic difficulties in developing it, coupled with lack of strong economic interests, are the reasons why still no such vaccine is commercially available today. Several types of vaccines are being developed at research centres, with some kind of caries vaccines being considered to diminish or prevent dental caries' impact on young people.
Lactobacillales are an order of gram-positive, low-GC, acid-tolerant, generally nonsporulating, nonrespiring, either rod-shaped (bacilli) or spherical (cocci) bacteria that share common metabolic and physiological characteristics. These bacteria, usually found in decomposing plants and milk products, produce lactic acid as the major metabolic end product of carbohydrate fermentation, giving them the common name lactic acid bacteria (LAB).
Dental caries, also known as tooth decay, is uncommon among companion animals. The bacteria Streptococcus mutans and Streptococcus sanguis cause dental caries by metabolising sugars. Prehistoric primates eating fruit suffer from cavities.
Extracellular polymeric substances (EPSs) are natural polymers of high molecular weight secreted by microorganisms into their environment. EPSs establish the functional and structural integrity of biofilms, and are considered the fundamental component that determines the physicochemical properties of a biofilm. EPS in the matrix of biofilms provides compositional support and protection of microbial communities from the harsh environments. Components of EPS can be of different classes of polysaccharides, lipids, nucleic acids, proteins, Lipopolysaccharides, and minerals.
Oral microbiology is the study of the microorganisms (microbiota) of the oral cavity and their interactions between oral microorganisms or with the host. The environment present in the human mouth is suited to the growth of characteristic microorganisms found there. It provides a source of water and nutrients, as well as a moderate temperature. Resident microbes of the mouth adhere to the teeth and gums to resist mechanical flushing from the mouth to stomach where acid-sensitive microbes are destroyed by hydrochloric acid.
Tooth remineralization is the natural repair process for non-cavitated tooth lesions, in which calcium, phosphate and sometimes fluoride ions are deposited into crystal voids in demineralised enamel. Remineralization can contribute towards restoring strength and function within tooth structure.
Willoughby Dayton Miller (1853–1907) was an American dentist and the first oral microbiologist.
Oral ecology is the microbial ecology of the microorganisms found in mouths. Oral ecology, like all forms of ecology, involves the study of the living things found in oral cavities as well as their interactions with each other and with their environment. Oral ecology is frequently investigated from the perspective of oral disease prevention, often focusing on conditions such as dental caries, candidiasis ("thrush"), gingivitis, periodontal disease, and others. However, many of the interactions between the microbiota and oral environment protect from disease and support a healthy oral cavity. Interactions between microbes and their environment can result in the stabilization or destabilization of the oral microbiome, with destabilization believed to result in disease states. Destabilization of the microbiome can be influenced by several factors, including diet changes, drugs or immune system disorders.
Glucansucrase is an enzyme in the glycoside hydrolase family GH70 used by lactic acid bacteria to split sucrose and use resulting glucose molecules to build long, sticky biofilm chains. These extracellular homopolysaccharides are called α-glucan polymers.
Tooth pathology is any condition of the teeth that can be congenital or acquired. Sometimes a congenital tooth diseases are called tooth abnormalities. These are among the most common diseases in humans The prevention, diagnosis, treatment and rehabilitation of these diseases are the base to the dentistry profession, in which are dentists and dental hygienists, and its sub-specialties, such as oral medicine, oral and maxillofacial surgery, and endodontics. Tooth pathology is usually separated from other types of dental issues, including enamel hypoplasia and tooth wear.
Plaque hypotheses are theories to explain the role of plaque bacteria in dental caries and in periodontitis. They rely heavily on the postulates of Koch and on the work of Louis Pasteur (1822–1895). Changing perceptions have altered treatment models.