Iron(III) oxide or ferric oxide is the inorganic compound with the formula Fe2O3. It is one of the three main oxides of iron, the other two being iron(II) oxide (FeO), which is rare; and iron(II,III) oxide (Fe3O4), which also occurs naturally as the mineral magnetite. As the mineral known as hematite, Fe2O3 is the main source of iron for the steel industry. Fe2O3 is readily attacked by acids. Iron(III) oxide is often called rust, and to some extent this label is useful, because rust shares several properties and has a similar composition; however, in chemistry, rust is considered an ill-defined material, described as Hydrous ferric oxide.
Dental products are specially fabricated materials, designed for use in dentistry. There are many different types of dental products, and their characteristics vary according to their intended purpose.
Zinc sulfate describes a family of inorganic compounds with the formula ZnSO4(H2O)x. All are colorless solids. The most common form includes water of crystallization as the heptahydrate, with the formula ZnSO4·7H2O. It was historically known as "white vitriol". Zinc sulfate and its hydrates are colourless solids.
Zinc oxide is an inorganic compound with the formula ZnO. It is a white powder that is insoluble in water. ZnO is used as an additive in numerous materials and products including cosmetics, food supplements, rubbers, plastics, ceramics, glass, cement, lubricants, paints, sunscreens, ointments, adhesives, sealants, pigments, foods, batteries, ferrites, fire retardants, semi conductors, and first-aid tapes. Although it occurs naturally as the mineral zincite, most zinc oxide is produced synthetically.
Zinc sulfide is an inorganic compound with the chemical formula of ZnS. This is the main form of zinc found in nature, where it mainly occurs as the mineral sphalerite. Although this mineral is usually black because of various impurities, the pure material is white, and it is widely used as a pigment. In its dense synthetic form, zinc sulfide can be transparent, and it is used as a window for visible optics and infrared optics.
Zinc oxide eugenol (ZOE) is a material created by the combination of zinc oxide and eugenol contained in oil of cloves. An acid-base reaction takes place with the formation of zinc eugenolate chelate. The reaction is catalysed by water and is accelerated by the presence of metal salts. ZOE can be used as a dental filling material or dental cement in dentistry. It is often used in dentistry when the decay is very deep or very close to the nerve or pulp chamber. Because the tissue inside the tooth, i.e. the pulp, reacts badly to the drilling stimulus, it frequently becomes severely inflamed and precipitates a condition called acute or chronic pulpitis. This condition usually leads to severe chronic tooth sensitivity or actual toothache and can then only be treated with the removal of the nerve (pulp) called root canal therapy. For persons with a dry socket as a complication of tooth extraction, packing the dry socket with a eugenol-zinc oxide paste on iodoform gauze is effective for reducing acute pain. The placement of a ZOE "temporary" for a few to several days prior to the placement of the final filling can help to sedate the pulp. But, ZOE had in vitro cytotoxicity majorly due to release of Zn ions, not eugenol. In spite of severe in vitro cytotoxicity, ZOE showed relatively good biocompatibility in animal study when ZOE was applied on dentin. When ZOE was used as dentin-protective based materials, use of dental composite resin on ZOE was strongly prevented due to its inhibition of resin polymerization through radical scavenging effect. It is classified as an intermediate restorative material and has anaesthetic and antibacterial properties. The exact mechanism of anesthetic effect from ZOE was not revealed perfectly, but possibly through anti-inflammatory effect, modulating immune-cells to less inflamed status.
Dental restoration, dental fillings, or simply fillings are treatments used to restore the function, integrity, and morphology of missing tooth structure resulting from caries or external trauma as well as to the replacement of such structure supported by dental implants. They are of two broad types—direct and indirect—and are further classified by location and size. A root canal filling, for example, is a restorative technique used to fill the space where the dental pulp normally resides.
In dentistry, inlays and onlays are used to fill cavities, and then cemented in place in the tooth. This is an alternative to a direct restoration, made out of composite, amalgam or glass ionomer, that is built up within the mouth.
Iron(III) phosphate, also ferric phosphate, is the inorganic compound with the formula FePO4. Several related materials are known, including four polymorphs of FePO4 and two polymorphs of the dihydrate FePO4·(H2O)2. These materials find few technical applications as well as occurring in the mineral kingdom.
A glass ionomer cement (GIC) is a dental restorative material used in dentistry as a filling material and luting cement, including for orthodontic bracket attachment. Glass-ionomer cements are based on the reaction of silicate glass-powder and polyacrylic acid, an ionomer. Occasionally water is used instead of an acid, altering the properties of the material and its uses. This reaction produces a powdered cement of glass particles surrounded by matrix of fluoride elements and is known chemically as glass polyalkenoate. There are other forms of similar reactions which can take place, for example, when using an aqueous solution of acrylic/itaconic copolymer with tartaric acid, this results in a glass-ionomer in liquid form. An aqueous solution of maleic acid polymer or maleic/acrylic copolymer with tartaric acid can also be used to form a glass-ionomer in liquid form. Tartaric acid plays a significant part in controlling the setting characteristics of the material. Glass-ionomer based hybrids incorporate another dental material, for example resin-modified glass ionomer cements (RMGIC) and compomers.
A luting agent is a dental cement connecting the underlying tooth structure to a fixed prosthesis. To lute means to glue two different structures together. There are two major purposes of luting agents in dentistry – to secure a cast restoration in fixed prosthodontics, and to keep orthodontic bands and appliances in situ.
In dentistry, amalgam is a liquid mercury and metal alloy mixture used to fill cavities caused by tooth decay. Low-copper amalgam commonly consists of mercury (50%), silver (~22–32%), tin (~14%), zinc (~8%) and other trace metals.
Dental cements have a wide range of dental and orthodontic applications. Common uses include temporary restoration of teeth, cavity linings to provide pulpal protection, sedation or insulation and cementing fixed prosthodontic appliances. Recent uses of dental cement also include two-photon calcium imaging of neuronal activity in brains of animal models in basic experimental neuroscience.
Mineral trioxide aggregate (MTA) was developed for use as a dental root repair material by Mahmoud Torabinejad. It is formulated from commercial Portland cement, combined with bismuth oxide powder for radio-opacity. MTA is used for creating apical plugs during apexification, repairing root perforations during root canal therapy, and treating internal root resorption. This can be used for root-end filling material and as pulp capping material. Originally, MTA was dark gray in color, but white versions have been on the market since 2002.
Zinc compounds are chemical compounds containing the element zinc which is a member of the group 12 of the periodic table. The oxidation state of zinc in most compounds is the group oxidation state of +2. Zinc may be classified as a post-transition main group element with zinc(II). Zinc compounds are noteworthy for their nondescript behavior, they are generally colorless, do not readily engage in redox reactions, and generally adopt symmetrical structures.
Dental compomers, also known as polyacid-modified resin composite, are used in dentistry as a filling material. They were introduced in the early 1990s as a hybrid of two other dental materials, dental composites and glass ionomer cement, in an effort to combine their desirable properties: aesthetics for dental composites and the fluoride releasing ability for glass ionomer cements.
Zinc borate is an inorganic compound, a borate of zinc. It is a white crystalline or amorphous powder insoluble in water. Its toxicity is low. Its melting point is 980 °C.
Zinc ferrites are a series of synthetic inorganic compounds of zinc and iron (ferrite) with the general formula of ZnxFe3−xO4. Zinc ferrite compounds can be prepared by aging solutions of Zn(NO3)2, Fe(NO3)3, and triethanolamine in the presence and in the absence of hydrazine, or reacting iron oxides and zinc oxide at high temperature. Spinel (Zn, Fe) Fe2O4 appears as a tan-colored solid that is insoluble in water, acids, or diluted alkali. Because of their high opacity, zinc ferrites can be used as pigments, especially in applications requiring heat stability. For example, zinc ferrite prepared from yellow iron oxide can be used as a substitute for applications in temperatures above 350 °F (177 °C). When added to high corrosion-resistant coatings, the corrosion protection increases with an increase in the concentration of zinc ferrite.
Zinc titanate, also known as zinc titanium oxide, is an inorganic compound existing in three major forms: ZnTiO3 (ZnO-TiO2), Zn2TiO4 (2ZnO-TiO2) and Zn2Ti3O8 (2ZnO-3TiO2). It is used as a regenerable catalyst, a pigment and a sorbent of sulfur compounds at elevated temperatures. It is a white powder that is insoluble in water.
Dental cermets, or silver cermets, are a type of restorative material dentists use to fill tooth cavities.
