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In situ Compressive Loading and Correlative Noninvasive Imaging of the Bone-periodontal Ligament-tooth Fibrous Joint
Published on: March 7, 2014
Small unilateral jaw gap variations: equilibrium changes, co-contractions and joint forces
H J Schindler1, J Lenz, J C Türp
1Research Group Biomechanics, Institute for Mechanics, University of Karlsruhe, Karlsruhe, Germany.
Journal of Oral Rehabilitation
|August 15, 2009
Summary
Small jaw discrepancies after dental reconstruction can occur. This study investigated their effects on muscle co-contraction, joint forces, and bite force distribution during jaw closing.
Area of Science:
- Dental Mechanics
- Biomechanics
- Masticatory System
Background:
- Complex prosthetic reconstructions can lead to minor vertical jaw discrepancies.
- Mandibular deformation allows for bilateral tooth contacts during intercuspation despite these discrepancies.
- The simultaneous effects on muscle activity, joint forces, and bite force application points remain unexamined.
Purpose of the Study:
- To investigate variations in masticatory muscle co-contraction, temporomandibular joint (TMJ) reaction forces, and the bite force reduction point.
- To analyze these factors in an experimental intercuspation model simulating one anterior and two posterior force transmission points.
Main Methods:
- Simulated experimental intercuspation using defined anterior and posterior force transmission points.
- Measurement of masticatory muscle co-contraction.
- Analysis of temporomandibular joint reaction forces.
- Determination of the bite force reduction point on the maxillary occlusion plane.
Main Results:
- Variations in vertical jaw distances were correlated with changes in muscle co-contraction patterns.
- Significant alterations in temporomandibular joint reaction forces were observed.
- The point of application of the resultant bite force vector (reduction point) showed distinct variations based on simulated jaw discrepancies.
Conclusions:
- Even small vertical jaw discrepancies can influence masticatory biomechanics.
- Understanding these biomechanical changes is crucial for optimizing prosthetic reconstructions.
- Further research is needed to fully elucidate the clinical implications of these findings in dental rehabilitation.
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