Root Fracture Mechanism of Foundation Restoration.

• Takahashi Hidekazu

  Advanced Biomaterials, Department of Restorative Science, Division of Oral Health Care, Graduate School, Tokyo Medical and Dental University

Bibliographic Information

Other Title

• 支台築造歯の歯根破折のメカニズム

Abstract

This paper reviews the factors of root fracture of endodontically treated teeth with a foundation restoration and designs of the foundation restoration for avoiding root fracture.<BR>The strength and elastic modulus of metallic materials for a foundation restoration are stronger and greater than those of dentin, respectively; the significant strength of the metallic post is not easy to break; however, the great elastic modulus distributes occlusal load to the radicular dentin, and as a result, the stress is concentrated at the apex of the post and cervical dentin close to the crestal bone ridge. The intensity of the stresses at these stress-concentrated points varies by such as the post length, crestal bone ridge height, and residual intact tooth amount. Root fracture does not occur when the amount of radicular dentin at these stress concentrated points is sufficient. If the elastic modulus of the post material is similar to that of the radicular dentin, stress distribution to the radicular dentin will decrease, however great flexural strength of the post is required. The actual fracture pattern is analyzed by the fracture test under static loading. The fracture pattern of the fracture test is not completely identical to the clinical fracture pattern. The actual fracture crack propagates by repeated loading; therefore, evaluation of the fracture test under cyclic loading is now a research concern. Minimal tooth grinding is essential to prevent root fracture; nevertheless, the design of the foundation restoration without root fracture is associated with dropping out of the fundamental restoration. The dentist must design a suitable foundation restoration with adequate retention while minimizing subsequent root fracture.

Journal

• Nihon Hotetsu Shika Gakkai Zasshi

  Nihon Hotetsu Shika Gakkai Zasshi 45 (6), 669-678, 2001

  Japan Prosthodontic Society

Keywords

• foundation restoration
• root fracture
• stress concentration
• elastic modulus
• cyclic fatigue

Details

• CRID: 1390282679389703808
• NII Article ID: 10007937282
• NII Book ID: AN00197911
• DOI: 10.2186/jjps.45.669
• ISSN: 1883177X
• ISSN: 03895386
• Web Site: http://www.jstage.jst.go.jp/article/jjps1957/45/6/45_6_669/_pdf
• Web Site: https://search.jamas.or.jp/link/ui/2002127863
• Text Lang: ja
• Data Source:
  • JaLC
  • Crossref
  • CiNii Articles
• Abstract License Flag: Disallowed