Investigation of arch structure of granular assembly in the trapdoor test using digital RGB photoelastic analysis

The successful restoration of teeth requires a good connection between the inlay and natural tissue. A strong bond may improve retention and reinforce tooth structure. The purpose of this study was to evaluate the influence of cement layer thickness on contraction stress generated during photopolymerization, and to determine the changes in stress state of the cement occurring during aging in water (over 84 days). Two cements were used: resin composite cement (NX3) and self-adhesive resin cement (Maxcem Elite Chroma). A cylindrical sample made of CuZn alloy was used to imitate the inlay. The stress state was measured by photoelastic analysis. The contraction stress of the inlay restoration was calculated for cement layer thicknesses of 25 µm, 100 µm, 200 µm, and 400 µm. For both tested materials, the lowest contraction stress was observed for the thinnest layer (25 µm), and this increased with thickness. Following water immersion, a significant reduction in contraction stress was observed due to hygroscopic expansion. Applying a thin layer (approximately 25 µm) of composite and self-adhesive resin cements resulted in high levels of expansion stresses (over −6 MPa) after water aging.

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Novel full-field automated photoelastic analysis technique

Optical Engineering ◽

10.1117/1.1290468 ◽

2000 ◽

Vol 39 (10) ◽

pp. 2689 ◽

Cited By ~ 4

Author(s):

Liu Tong

Keyword(s):

Full Field ◽

Analysis Technique ◽

Photoelastic Analysis

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Damage analysis and numerical simulation for failure process of a reinforced concrete arch structure

Computers & Structures ◽

10.1016/j.compstruc.2005.03.017 ◽

2005 ◽

Vol 83 (31-32) ◽

pp. 2609-2631 ◽

Cited By ~ 10

Author(s):

X.S. Tang ◽

J.R. Zhang ◽

C.X. Li ◽

F.H. Xu ◽

J. Pan

Keyword(s):

Numerical Simulation ◽

Reinforced Concrete ◽

Failure Process ◽

Damage Analysis ◽

Arch Structure

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Photoelastic Analysis on Different Retention Methods of Implant-Supported Prosthesis

Journal of Oral Implantology ◽

10.1563/aaid-joi-d-12-00200 ◽

2015 ◽

Vol 41 (3) ◽

pp. 258-263 ◽

Cited By ~ 1

Author(s):

Angélica Castro Pimentel ◽

Marcello Roberto Manzi ◽

Cristiane Ibanhês Polo ◽

Claudio Luiz Sendyk ◽

Maria da Graça Naclério-Homem ◽

...

Keyword(s):

Stress Distribution ◽

Axial Load ◽

Testing Machine ◽

Compressive Load ◽

Lower Intensity ◽

Photoelasticity Method ◽

Universal Testing ◽

Isochromatic Fringes ◽

Photoelastic Analysis ◽

Compressive Axial Load

The aim of this study was to evaluate the stress distribution of different retention systems (screwed, cemented, and mixed) in 5-unit implant-supported fixed partial dentures through the photoelasticity method. Twenty standardized titanium suprastructures were manufactured, of which 5 were screw retained, 5 were cement retained, and 10 were mixed (with an alternating sequence of abutments), each supported by 5 external hexagon (4.0 mm × 11.5 mm) implants. A circular polariscope was used, and an axial compressive load of 100 N was applied on a universal testing machine. The results were photographed and qualitatively analyzed. We observed the formation of isochromatic fringes as a result of the stresses generated around the implant after installation of the different suprastructures and after the application of a compressive axial load of 100 N. We conclude that a lack of passive adaptation was observed in all suprastructures with the formation of low-magnitude stress in some implants. When cemented and mixed suprastructures were subjected to a compressive load, they displayed lower levels of stress distribution and lower intensity fringes compared to the screwed prosthesis.

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