The Cracked Tooth – Part 1.
Crack Dynamics in Dental Hard Tissues.

The Cracked Tooth – Part 1.
Crack Dynamics in Dental Hard Tissues.

presented by:
Dr Masoud Hassan Zadeh

This presentation explores the dynamics of crack propagation in enamel and dentin, focusing on the fracture mechanics that govern these distinct dental hard tissues. It examines how cracks initiate and progress through the tooth, revealing both the strengths and weaknesses of its layered structure in resisting failure. Special attention is given to the dentin-enamel junction (DEJ) as a critical crack-stopping mechanism, highlighting its role in preventing catastrophic fractures. The discussion also addresses how variations in tissue composition and histological structure influence the direction, speed, and severity of crack propagation.

Aims & Objectives:

1) Learn about the fracture toughness and crack growth resistance of the inner and outer enamel layers, emphasising their distinct roles in protecting the tooth against structural failure.
2) Understand the role of the Dentin-Enamel Junction (DEJ) as a key barrier to crack propagation, preventing catastrophic fractures by dissipating stress at the interface.
3) Gain inisight into the role of mantle dentin in mitigating crack propagation, emphasising its unique properties and contribution to the tooth’s overall fracture resistance.
4) Learn about crack orientation and penetration patterns in dentin, focusing on how stress distribution is influenced by the structural alignment of stress planes.

Lecture Duration: 36 minutes.

Audio language: English.
Subtitles: English, Español.

English subtitles and Spanish translations are now available. Learn more.
Ya están disponibles los subtítulos en inglés y las traducciones al español. Más información.

Preview:

• Available Worldwide.
• Watch and rewind as often as you require.
• Internet connection required.
• 0.5 Hours of Verifiable Continuing Professional Development awarded with a personalised certificate.
• Course release date: 2025.
• No conflicts of interest declared.
• GDC Developmental Outcome Achieved: C
• AGD Subject Code: 250 – Operative (Restorative) Dentistry

Date content was last reviewed: 01 July 2025.
Date of next scheduled content review: 01 January 2026.

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