Showing papers on "Post and core published in 1998"

Comparison of the fracture resistances of pulpless teeth restored with a cast post and core or carbon-fiber post with a composite core

Abstract: Statement of problem. The survival of pulpless teeth restored with a post and core system is a controversial issue. Purpose. This study compared the fracture resistance of 2 types of restorations: teeth restored with prefabricated carbon-fiber posts and composite cores to cast dowel-core restored teeth. Material And Methods. A total of 44 recently extracted sound premolars were randomly distributed into 2 equal groups: group I, restored with prefabricated carbon-fiber post and a composite core; and group II, with custom-cast type III gold alloy post and cores. The size and shape of the posts were identical in the 2 groups. All teeth were fully covered with a nonprecious cast crown. Fracture resistance was measured by applying a point force at 45 degrees to the long angle of the tooth. Results. Mean fracture threshold was 103.7 ± 53.1 kg for group I versus 202.7 ± 125.0 kg for group II (differences significant with P =.003). In group II, however, fracture nearly always affected the tooth itself, whereas in group I, the post-core nearly always failed first. Conclusions. Significantly higher fracture thresholds were recorded for the cast post and core group. Teeth restored with cast posts typically showed fracture of the tooth, although at loads rarely occurring clinically. (J Prosthet Dent 1998;80:527-32.)

A new all-ceramic post and core system: clinical, technical, and in vitro results.

Abstract: Root-filled teeth with fractured or discolored coronal aspects invariably need to be restored by crowns. The prepared abutment tooth is usually reinforced by a metallic post and core system. The grayish discoloration of the root, and consequently of the gingiva, caused by the metal color may be an enormous esthetic disadvantage in the anterior teeth. In 1993 ceramic posts made of zirconia were introduced by the authors, allowing a new all-ceramic concept for nonvital abutment teeth. A new ceramic post and core system has now been developed with the idea of further improving esthetic appearance. In this system the core material is heat pressed directly onto the zirconia post. This article describes the material and the fabrication procedures (chairside and in the laboratory) of the system. Clinical results are presented. The retention of the core material is evaluated by in vitro tests.

Direct core buildup using a preformed crown and prefabricated zirconium oxide post

Abstract: This article describes a procedure that can produce a post and core in a reasonable chair time during a single session. With a preformed crown for core buildup, and being relatively rapid, this is a fairly simple procedure that has good results. (J Prosthet Dent 1998;80:730-2.)

Treatment planning extensively broken-down mandibular molars for post-and-core fabrication.

Abstract: Because of their unique radicular anatomy, mandibular molars require careful treatment planning for post-and-core fabrication. Indications for post-and-core fabrication for endodontically treated mandibular molars are discussed, and immediate and cast post-and-core techniques are reviewed. An alternative design for a cast post and core is also presented.

Dissolution of cement, root caries, fracture, and retrofit of post and cores.

Abstract: Fixed partial denture abutments severely damaged by dental caries or fracture present a challenge to the dentist. The fixed partial denture may need to be removed for endodontic treatment with post and core fabrication. Frequently, the existing fixed partial denture can be recycled as a provisional restoration. Retrofitting the post and core greatly improves the stabilization of the interim as well as the remake of the definitive fixed partial denture. This article describes a chair side procedure for retrofitting posts and cores and, at the same appointment, converting the original fixed partial denture to an effective provisional restoration.

Restoration of root canal treated teeth using carbon fiber posts

Abstract: The restoration of root canal treated teeth--because of the significant loss of tooth structure--is often achieved with post and core. However, post may generate stresses which lead to vertical root fracture and loss of the tooth. Since post design, material used and the post space preparation has significant influence on vertical fracture prevalence, broad investigation is in progress to find out the optimum procedure. During the last decade new prefabricated passive posts were introduced for postendodontic restorations. In order to collect information clinical trials have been performed on the reconstruction of root canal treated teeth using carbon fibe posts (COMPOSIPOST, RTD, France; C-POST, Bisco, USA). Adhesive technique was applied to cement posts in the root canal and for composite core reconstruction. The physical properties of carbon fiber posts and the composite core are very close to those of dentin. Post application is simple, does not require special skill and for the patients means minimum hazard. The position of the posts was controlled by radiography. During the 24 months observation period no failure was registered in patients treated (n = 55). Hence, we attribute our good results to the homogeneous reconstruction of the teeth. This procedure seems to be a good alternative to traditional cast metal dowel/cores or metal prefabricated posts.

Prefabricated post and core material versus custom-cast post and core in a maxillary first premolar tooth: review of literature and management of a clinical case

Abstract: When an abutment tooth is endodontically treated and is intact except for the access opening, the amount of tooth structure remaining after tooth preparation must be carefully assessed. If only a thin peripheral shell of tooth remains after reduction (which occurs frequently in incisors, canines and premolars), a cast post and core should be fabricated. In this article, the use of a prefabricated post and core material versus a custom-cast post and core is reviewed. A clinical management of an improperly restored endodontically treated maxillary first premolar tooth is also presented.