Abstract
Animals with elodont dentition and unfused mandible symphyses are hypothesized to have symmetric incisor morphology. Since these animals maintain their teeth by gnawing, they may provide physiologic feedback on mechanical function when unilateral mandible defects are created that manifest as ipsilateral changes in tooth structure. This defect model would potentially generate important information on the functional/mechanical properties of implants. Rats’ and rabbits’ mandibles and teeth are analyzed with µCT at baseline and post-intervention (n = 8 for each). Baseline incisors were compared. In a unilateral mandible pilot study, defects—ranging from critical size defect to complete ramus osteotomies—were created to assess effect on dentition (rats, n = 7; rabbits, n = 6). Within 90% confidence intervals, animals showed no baseline left/right differences in their incisors. There are apparent dental changes associated with unilateral defect type and location. Thus, at baseline, animals exhibit statistically significant incisor symmetry and there is an apparent relationship between mandible defect and incisor growth. The baseline symmetry proven here sets the stage to study the degree to which hemi-mandible destabilizing procedures result in measurable & reproducible disruption of dental asymmetry. In a validated model, an implant designed to function under load that prevents incisor asymmetry would provide supporting evidence that the implant has clinically useful load-bearing function.
Highlights
IntroductionThe larger project of which this study is a part is to develop a craniofacial load-bearing defect model that enables physiologic identification of the minimum mechanical properties required in a bone graft to reconstitute a defect in a highly stressed skeletal zone
The larger project of which this study is a part is to develop a craniofacial load-bearing defect model that enables physiologic identification of the minimum mechanical properties required in a bone graft to reconstitute a defect in a highly stressed skeletal zone. This model would ideally possess the following attributes: (1) allow for an objective quantifiable measure of physiologically relevant mechanical function in bone, (2) provide longitudinal information on the function of a skeletal unit; function that is degraded by a defect but restored with skeletal reconstitution, (3) allows for the implantation of plates and/or loadbearing bone substitutes in the test region, and (4) be relevant and translatable to human applications
(2) Disuse of the elodont dentition is quickly reflected in uncontrolled growth and altered morphology of the erupted crowns [2,3]. (3) The mandible is two hemi-mandibles that are joined by a non-bony fibro-cartilaginous symphysis
Summary
The larger project of which this study is a part is to develop a craniofacial load-bearing defect model that enables physiologic identification of the minimum mechanical properties required in a bone graft to reconstitute a defect in a highly stressed skeletal zone. The fibrous symphysis articulates the two hemi-mandibles allowing the animal to rotate one side about the other This angular movement, which can be up to 40◦ in the rat, enhances the animals’ ability to preferentially chew on one side of the mandible while leaving the contralateral side less mechanically loaded [4]
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.