dental implantation cho young kuen
TRANSCRIPT
Dental Implantation
Cho Young Kuen
The different stress distribution between normal and abnormal ratio of crown
Introductory
The most frequent surgical procedure performed upon humans is dental extraction.
The most frequently employed prosthesis is the complete or partial denture. (Cranin, Worthington, 1988)
Introductory
Analyzing force transfer at the bone-implant interface is an essential step in the overall analysis of loading.
Both implant and bone should be stressed within a certain range for physiologic homeostasis.
(Static, dynamic and fatigue behaviors of dental implant using finite element method)
Introductory
3 steps for implantation
1. Cut section
2. Implant the fixture
3. Implant the others
(abutment, metal frame, occlusal material)
(Http://catalog.nucleusinc.com)
Introductory Assumptions
1. The crown ratio of the dente is not always same in every dental implantation.
2. If trabecula bone density is not enough for implatation, how stress distribution is occurred?
(Http://catalog.nucleusinc.com)
Biomaterials
Parts Materials Young’s modulus (MPa)
Poisson’s ratio
Crown Porcelain 68900 0.28
Implant Titanium 110000 0.35
Cortical Bone Cortical Bone
13400 0.30
Spongy Bone Spongy Bone
1370 0.30
Simulation purpose
Simulate for physical reaction on same structure but different ratio of crown
Case 1. Normal Case 2. Abnormal ( 1.5 times ) Case 3. Abnormal ( 2.0 times )
Why do abnormal?
1. It’s caused by position of transplant. (e.g. a cuspid, a grinder)
2. Jawbone is going down (then turn it black).
Meshing
Meshing by Hypermesh
1.Crown
2.Implant
3.Cortical outer
4.Spongy
5.Cortical inner
Analysis
Loading phase FX : -17.1 N FY : -114.6 N FZ : 23.4 N FT : 118.2 N
Analyze by ANSYS10.0 Material properties
Result
Normal
Result
Abnormal ( 1.5 times )
Result
Abnormal ( 2.0 times )
Result
I make a path to measure the stress by 90 nodes on the contact surface
between cortical outer bone and implant.
Result
Discussion
• There are certain parts the maximum stress is occurred.
• Some parts have more stress to take overload without overall failure.
• It’s means that the life of implant can be longer to modify the shape or to fill in the trabecula bone.
Further study
• We assumed that the crown ratio is different between each dente, however, it can be make up by shape of crown.
• So we need to analyze using various types of crown.
Any Questions?
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