Biomaterial Database

Fracture resistance of human enamel and three all-ceramic crown systems on extracted teeth. 1996

S S Scherrer, and W G De Rijk, and U C Belser

Department of Fixed Prosthodontics and Occlusion, School of Dentistry, University of Geneva, Switzerland.

This in vitro study measured the fracture resistance of intact extracted molars and three types of all-ceramic crowns; feldspathic porcelain, glass-ceramic, and glass-infiltrated alumina. All crowns were of a simplified three-cusp occlusal configuration, and were placed on prepared, extracted third molars. The ceramic crowns were bonded to dentin with a resin composite cement, except for 10 of the feldspathic crowns, which were luted with zinc phosphate cement. The fracture resistances was measured using a spherical steel indenter that contacted the occlusal surface at three points. A total of 40 ceramic crowns and 50 extracted maxillary third molars were tested. The Weibull distribution was used for data analysis. Intact extracted teeth were significantly stronger than all-ceramic crowns. Of the ceramic restorations, the glass-infiltrated alumina crowns exhibited the highest fracture resistance.

UI	MeSH Term	Description	Entries
D008422	Materials Testing	The testing of materials and devices, especially those used for PROSTHESES AND IMPLANTS; SUTURES; TISSUE ADHESIVES; etc., for hardness, strength, durability, safety, efficacy, and biocompatibility.	Biocompatibility Testing,Biocompatible Materials Testing,Hemocompatibility Testing,Testing, Biocompatible Materials,Testing, Hemocompatible Materials,Hemocompatibility Testings,Hemocompatible Materials Testing,Materials Testing, Biocompatible,Materials Testing, Hemocompatible,Testing, Biocompatibility,Testing, Hemocompatibility,Testing, Materials,Testings, Biocompatibility
D008855	Microscopy, Electron, Scanning	Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.	Scanning Electron Microscopy,Electron Scanning Microscopy,Electron Microscopies, Scanning,Electron Microscopy, Scanning,Electron Scanning Microscopies,Microscopies, Electron Scanning,Microscopies, Scanning Electron,Microscopy, Electron Scanning,Microscopy, Scanning Electron,Scanning Electron Microscopies,Scanning Microscopies, Electron,Scanning Microscopy, Electron
D008963	Molar	The most posterior teeth on either side of the jaw, totaling eight in the deciduous dentition (2 on each side, upper and lower), and usually 12 in the permanent dentition (three on each side, upper and lower). They are grinding teeth, having large crowns and broad chewing surfaces. (Jablonski, Dictionary of Dentistry, 1992, p821)	Molars
D002484	Cementation	The joining of objects by means of a cement (e.g., in fracture fixation, such as in hip arthroplasty for joining of the acetabular component to the femoral component). In dentistry, it is used for the process of attaching parts of a tooth or restorative material to a natural tooth or for the attaching of orthodontic bands to teeth by means of an adhesive.	Cementations
D003442	Crowns	A prosthetic restoration that reproduces the entire surface anatomy of the visible natural crown of a tooth. It may be partial (covering three or more surfaces of a tooth) or complete (covering all surfaces). It is made of gold or other metal, porcelain, or resin.	Dental Crowns,Crown, Dental,Crowns, Dental,Dental Crown,Crown
D003743	Dental Enamel	A hard thin translucent layer of calcified substance which envelops and protects the dentin of the crown of the tooth. It is the hardest substance in the body and is almost entirely composed of calcium salts. Under the microscope, it is composed of thin rods (enamel prisms) held together by cementing substance, and surrounded by an enamel sheath. (From Jablonski, Dictionary of Dentistry, 1992, p286)	Enamel,Enamel Cuticle,Dental Enamels,Enamel, Dental,Enamels, Dental,Cuticle, Enamel,Cuticles, Enamel,Enamel Cuticles,Enamels
D003776	Dental Porcelain	A type of porcelain used in dental restorations, either jacket crowns or inlays, artificial teeth, or metal-ceramic crowns. It is essentially a mixture of particles of feldspar and quartz, the feldspar melting first and providing a glass matrix for the quartz. Dental porcelain is produced by mixing ceramic powder (a mixture of quartz, kaolin, pigments, opacifiers, a suitable flux, and other substances) with distilled water. (From Jablonski's Dictionary of Dentistry, 1992)	Porcelain,Porcelain, Dental,Dental Porcelains,Porcelains,Porcelains, Dental
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000537	Aluminum Oxide	An oxide of aluminum, occurring in nature as various minerals such as bauxite, corundum, etc. It is used as an adsorbent, desiccating agent, and catalyst, and in the manufacture of dental cements and refractories.	Alumina,Alumina Ceramic,Aluminum Oxide (Al130O40),Aluminum Oxide (Al2O),Aluminum Oxide (AlO2),Bauxite,Corundum,Sapphire,Ceramic, Alumina,Oxide, Aluminum
D015036	Zinc Phosphate Cement	A material used for cementation of inlays, crowns, bridges, and orthodontic appliances and occasionally as a temporary restoration. It is prepared by mixing zinc oxide and magnesium oxide powders with a liquid consisting principally of phosphoric acid, water, and buffers. (From Bouchers' Clinical Dental Terminology, 3d ed)	Cement, Zinc Phosphate