Finish lines in fixed prosthodontics.

Ideally, all finish lines should be placed supragingivally. Due to esthetic and carious considerations, however, subgingival placement of the finish line is preferred. No one type of finish line can be used for all crown preparations. In lower anterior teeth or periodontically-treated teeth, the knife-edge finish line appears to be the treatment of choice. In short teeth and preparations for porcelain and porcelain-gold crowns, the full shoulder bevelled preparation is the treatment of choice. In full gold and acrylic veneered gold crowns, as in endodontically-treated teeth, the chamfer preparation is the treatment of choice.