Dental arch pain triggered by hot or cold liquids or foods is a frequent problem worldwide and is known among dentist as hypersensitivity of the dentine, a live tissue connected by microtubes to the nerve, which becomes exposed whenever tooth enamel has flaws due to natural wear or factors linked to acid diets, stomach reflux or gum recession. Dentists’ treatment of the problem may soon enlist a new ally thanks to the launch of a material that promises to fight local pain by reconstituting the dentine. The firm Vitrovita Bio, which is being formed by a group of researchers from the Federal University of São Carlos (UFSCar), plans to produce Biosilicato, the name of the product that the firm has registered. It is a bioactive powder made out of silicate, sodium, potassium, calcium and phosphorus that can bond with tooth enamel. This is one of the three companies formed as a result of projects conducted in two São Paulo State universities.
The other two enterprises are ProtMat Materiais Avançados, set up within Inove (the Innovation and Entrepreneurship Incubator) in the town of Guaratinguetá (inner-state São Paulo) and specializing in the production of ceramic blocks used to make dental prostheses, thanks to a project started at the Lorena School of Engineering at the University of São Paulo (USP), and Binderware, another UFSCar and USP spin-off that focuses on the production of a restoration cement for endodontics, the area of dentistry that specializes in ailments of the tooth pulp and nerves.
Vitrovita’s Biosilicato is a material that is deposited in the opening of the microtubes in the dentine, forming new layers that protect the nerve from hot or chilled liquids, which is what triggers the hypersensitivity. The chief advantage of this new material relative to those used in conventional treatments is its capacity for reacting and binding with tooth enamel, enabling treatment that is fast and long lasting. “Just a few minutes after it is applied, Biosilicato induces the formation of a layer of hydroxyapatite, a substance with the same chemical composition and structure as the mineral tissue in the teeth and bones”, says materials engineer Edgar Dutra Zanotto, a professor at the UFSCar Vitreous Materials Laboratory of the Materials Engineering Department and one of the firm’s partners. Biosilicato has no toxic effects and, according to Zanotto, can also be used to re-mineralize the enamel after dental whitening, to recompose the bone mass in periodontal treatments (gum treatments) and to protect the pulp, in the case of an exposed nerve.
The studies that led to Biosilicato began in 2001 and were part of the master’s degree dissertation of materials engineer Christian Ravagnani, a partner in Vitrovita, under the guidance of Zanotto and of Professor Oscar Peitl. Researchers from USP’s School of Dentistry and Pharmaceutical Sciences in Ribeirão Preto also worked on the project. The development was financed by Pipe (Program for Innovative Research in Small Companies) and by the Intellectual Property Support program, both of which belong to FAPESP.
Binderware, which is also headquartered in São Carlos, hopes to start marketing this very year an aluminous restoration cement developed under the coordination of Professor Victor Carlos Pandolfelli, from UFSCar. The product, whose patent belongs to the university, was named EndoBinder. It is an extremely pure compound of calcium aluminate cement (aluminum and calcium oxides) mixed to additives that enable applications in the field of endodontics. “To date, our cement has been used successfully in three clinical cases: treatment of perforations in the tooth’s root canal walls, filling the end of the tooth’s root, and as a sealant when the tooth is being absorbed by the body itself. In this case, the cement creates a protective barrier in the absorption region”, explains engineer Hebert Rossetto, one of Binderware’s partners.
“EndoBinder is a mineral aggregate that represents a new generation of this type of material”, says engineer Tathiana Moreira, a Binderware director. According to her, the product takes less time to harden than the material used in the conventional treatment; its color is naturally white, similar to that of the dental structure; it has low porousness and good resistance to compression. The firm started operating early last year at the ParqTec incubator, in São Carlos, and last December it relocated to its own headquarters.
Established in December 2007, ProtMat is awaiting the go-ahead from Anvisa, Brazil’s National Sanitary Surveillance Agency, to start marketing its ceramic blocks for making dental prostheses and intermediary pillars. Pillars are the connectors between implants (the pins anchored to the bone) and the prosthesis. The ceramic materials chosen have compounds of zirconia stabilized with yttria or alumina. Zirconia is a synthetic ceramic made from zircon. “Ittrya stabilized zirconia is one of the ceramic materials with the highest resistance to fractures. Additionally, it has good features as a component of dental prosthesis, good adhesion to prosthesis surfacing ceramics and porcelains, and is highly translucent”, stresses engineer Claudinei dos Santos, who teaches in the graduate program at USP’s Lorena School of Engineering and is a ProtMat partner, along with Professor Carlos Elias, from IME (the Military Institute of Engineering) in Rio de Janeiro.
The development of this new ceramic material took place under FAPESP’s Young Researchers project and was completed in September 2008. “The project’s aim was to create in this country intermediary pillars of ceramic material to be used in dental implant systems”, explains Santos. “These pillars are usually made of metal, which is inconvenient because it reduces the esthetic quality of the prostheses, as they look darker when seen against the light. The idea was to replace these metal pillars by ceramic ones with high mechanical resistance and with a nicer appearance. So we created the ceramic blocks of zirconia that can be milled and transformed into pillars or into the actual prostheses.”
Based on digitized images of the models of a tooth, for example, a software program determines all the parameters for making the part. “Our company discovered that in the near future, several prostheses production centers are going to establish themselves in Brazil. Thus, we will be able to supply ceramic materials with mechanical properties and at competitive prices for consumption at these centers”, says Santos.
1. Development and characterization of biocompatible ceramic pillars made from ZrO2-Al2O3 composites (nº 04/13523-2); Type Young Researchers Program; Coordinator Claudinei dos Santos – USP; Investment R$ 233,935.00 and US$ 1,280.00 (FAPESP)
2. Development of an optimized and financially viable process for the production of biosilicate in the treatment of dentine hypersensitivity (nº 04/07435-3); Type Innovative Research in Small Companies (Pipe); Coordinator Christian Ravagnani – Vitrovita; Investment R$ 416,231.85 and US$ 121.64 (FAPESP)