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Quasistatic Mechanical Testing for Computer-Aided Design and Manufacturing Occlusal Veneers Cemented to Milled Dentin Analog Material
Published on: December 20, 2024
Cementum crack formation by repeated loading in vitro
Noriyoshi Noma1, Hiroshi Kakigawa, Yoshio Kozono
1Division of Periodontology, Department of Cariology and Periodontology, Kyushu Dental College, Kitakyushu, Japan.
Journal of Periodontology
|April 3, 2007
Summary
Repeated occlusal stresses can cause fatigue destruction, leading to cementum cracks on teeth. These cracks develop over time and may contribute to periodontal diseases.
Area of Science:
- Dental research
- Biomaterials science
- Periodontology
Background:
- Investigates the hypothesis that fatigue destruction occurs on tooth cementum due to repeated occlusal stresses.
- Examines the link between prolonged occlusal trauma and potential cemental damage.
Purpose of the Study:
- To determine if cemental fatigue destruction occurs under repeated occlusal loading.
- To analyze the development and progression of cracks in tooth cementum.
Main Methods:
- Five human premolars were subjected to 1 million cycles of 5.0 kgf compressive load along the tooth axis.
- Tooth surfaces were photographed, cracks were visualized with methylene blue, and areas were measured using image analysis software.
Main Results:
- Significant crack development observed on buccal, mesial, and distal cementum surfaces, not lingual.
- Crack areas increased significantly after 500,000 loadings.
- Cracks extended apically, averaging 0.67 mm after 1 million loadings.
Conclusions:
- Repeated loading causes cementum cracks at the cervix, extending towards the root apex.
- These cracks suggest occlusal stresses (e.g., bruxism) may initiate site-specific attachment loss.
- This process is a potential factor in the development of periodontal diseases.
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