Biomaterial Database

Influence of the shape core on custom cast dowel and core removal by ultrasonic energy. 2007

E C Queiroz, and M S Menezes, and J C G Biffi, and C J Soares

Department of Endodontics, Dentistry School, Federal University of Uberlândia, Minas Gerais, Brazil.

The aim of this study was to assess the influence of the shape of custom cast dowel and cores on their removal by the use of ultrasound technique. Twenty-four single-rooted bovine teeth were prepared and had cast dowel fixed with zinc phosphate cement. The teeth were randomly divided into two groups: group I- received custom cast dowel and cores made without the coronal portion anatomy, simulating removal this portion with a bur, and group II- received cores that reproduced the coronal anatomy. Both were treated with an ultrasound device in two three-minute cycles (US). The force necessary for dowel removal was determined using a mechanical test machine. In the second stage of the study, the custom cast dowel and cores were again cemented and no ultrasound vibration was used on them (C). Data were submitted to the two-way anova (2 x 2) and Tukey test (P < 0.05), resulting in decreased tensile strength values (Kgf): GIC (49.85 +/- 11.10); GIIC (48.22 +/- 11.09); GIIUS (32.36 +/- 6.21) and GIUS (8.0 +/- 7.52). It was concluded that the shape of the core without the anatomic coronal portion facilitated removal of intra-radicular retention only when associated with the use of ultrasound.

UI	MeSH Term	Description	Entries
D011176	Post and Core Technique	Use of a metal casting, usually with a post in the pulp or root canal, designed to support and retain an artificial crown.	Dental Dowels,Dental Dowel,Dowel, Dental,Dowels, Dental,Post Technic,Post Technique,Post and Core Technic,Post-Core Technic,Post Technics,Post Techniques,Post-Core Technics,Technic, Post,Technic, Post-Core,Technics, Post,Technics, Post-Core,Technique, Post,Techniques, Post
D011897	Random Allocation	A process involving chance used in therapeutic trials or other research endeavor for allocating experimental subjects, human or animal, between treatment and control groups, or among treatment groups. It may also apply to experiments on inanimate objects.	Randomization,Allocation, Random
D002417	Cattle	Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.	Beef Cow,Bos grunniens,Bos indicus,Bos indicus Cattle,Bos taurus,Cow,Cow, Domestic,Dairy Cow,Holstein Cow,Indicine Cattle,Taurine Cattle,Taurus Cattle,Yak,Zebu,Beef Cows,Bos indicus Cattles,Cattle, Bos indicus,Cattle, Indicine,Cattle, Taurine,Cattle, Taurus,Cattles, Bos indicus,Cattles, Indicine,Cattles, Taurine,Cattles, Taurus,Cow, Beef,Cow, Dairy,Cow, Holstein,Cows,Dairy Cows,Domestic Cow,Domestic Cows,Indicine Cattles,Taurine Cattles,Taurus Cattles,Yaks,Zebus
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
D003786	Dental Pulp Cavity	The space in a tooth bounded by the dentin and containing the dental pulp. The portion of the cavity within the crown of the tooth is the pulp chamber; the portion within the root is the pulp canal or root canal.	Pulp Canal,Pulp Chamber,Root Canal,Cavities, Dental Pulp,Cavity, Dental Pulp,Dental Pulp Cavities,Pulp Cavities, Dental,Pulp Cavity, Dental,Canal, Pulp,Canal, Root,Canals, Pulp,Canals, Root,Chamber, Pulp,Chambers, Pulp,Pulp Canals,Pulp Chambers,Root Canals
D000704	Analysis of Variance	A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.	ANOVA,Analysis, Variance,Variance Analysis,Analyses, Variance,Variance Analyses
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D014465	Ultrasonics	A subfield of acoustics dealing in the radio frequency range higher than acoustic SOUND waves (approximately above 20 kilohertz). Ultrasonic radiation is used therapeutically (DIATHERMY and ULTRASONIC THERAPY) to generate HEAT and to selectively destroy tissues. It is also used in diagnostics, for example, ULTRASONOGRAPHY; ECHOENCEPHALOGRAPHY; and ECHOCARDIOGRAPHY, to visually display echoes received from irradiated tissues.	Ultrasonic
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
D017268	Dental Prosthesis Retention	Holding a DENTAL PROSTHESIS in place by its design, or by the use of additional devices or adhesives.	Prosthesis Retention, Dental,Retention, Dental Prosthesis