Implant-supported single tooth replacement in the aesthetic region: a complex challenge.

The placement of a single tooth implant-supported restoration in the maxillary anterior area still presents a difficult challenge. To address this challenge, various methods and techniques have been proposed. The learning objective of this article is to present a particular clinical protocol for achieving predictable aesthetic restoration, even under the relatively difficult circumstances involving thin, highly scalloped gingiva and high lip line. A clinical case is used to illustrate the presentation of implant surgery, bone regeneration, connective tissue graft, provisionalization, and placement of the definitive prosthetic restorations. The use of pressure to expand soft tissue is described, and the importance of papillae protection is emphasized.

Influence of the implant position on the aesthetics of the restoration.

Well-placed implants are a prerequisite to achieving functional as well as aesthetically successful implant-supported restorations. In addition to sufficient bone volume, a precise emergence profile is an important factor in obtaining the optimal result of the final restoration, presenting a natural gingival silhouette. Restorations with a ridge lap design are no longer acceptable. The learning objective of this article is to review implant placement with emphasis on the factors that influence implant position and angulation. Anatomic discrepancies between the natural tooth root and the implant are discussed in context of treatment planning, including the position and direction of the implants, determined by the anticipated prosthetic restorations. The sagittal plane of implant position is reviewed versus horizontal or vertical placement in the anterior as well as posterior region. Function, comfort, access for hygiene, and aesthetics are the four essential requirements for an implant-supported restoration.

In vitro studies on genotoxicity and cytotoxicity of the anticancer drugs cisplatin and cofplaton, a caffeine-8-ether plus cisplatinum compound.

The cytotoxic and genotoxic properties of the newly designed anticancer drug 'cofplaton' were investigated. Since cofplaton is a cisplatin (CDDP) plus caffeine compound, the widely applied anticancer drug CDDP alone or in combination with caffeine was studied in parallel. As measured by the MTT test the cytotoxicity of the two drugs was comparable, but cofplaton exhibited significantly fewer genotoxic side effects than CDDP in the chromosome aberration test as well as in the SCE assay. First results from animal studies indicate that cofplaton exerts antitumor activity comparable to CDDP. Because of its relatively low genotoxicity, cofplaton seems to be a promising drug in human anticancer therapy.