Advisory Committee Chair
Michael McCracken
Advisory Committee Members
Amjad Javed
Jack E Lemons
Mark S Litaker
Firoz Rahemtulla
Document Type
Thesis
Date of Award
2008
Degree Name by School
Master of Science (MS) School of Dentistry
Abstract
Titanium-aluminum-vanadium (Ti-6Al-4V) tacks were placed in the tibiae of 10 female wild type (Runx2 flox/+ or Runx2 flox/flox) and heterozygous (Runx2+/-, ColII Cre) mice littermates to examine healing and bone response. Animals were divided into control and test groups of 5 each. A novel generation of Runx2 knock-out mice where the gene is only deleted in chondrocytes was used. Ten days after implant surgery, specimens were recovered and prepared for histological, histomorphometric, and micro-CT morphometric analysis. Histological examination revealed that wild type animals presented larger regions of bone formation and endochondral ossification when compared to heterozygous mice. Micro-CT morphometric analysis of the same bones demonstrated that tissue response area (TRA) was larger in the wild type (1.06mm2 ± 0.25) than in the heterozygous mice (0.60mm2 ± 0.28). This result was statistically different when groups were compared (P< 0.05). In addition, bone formation area (BFA) for the wild type was 0.25mm2 (±0.06) while BFA for heterozygous mice was 0.12mm2 (± 0.05). This represented a significantly different (P< 0.05). Bone formation around implant sites in wild type animals was statistically greater than the heterozygous group. Histological and micro-structural findings were supported and quantified by histomorphometric analysis, which established that titanium implants placed in the wild type group showed greater bone-to-implant contact percent (76.9 ± 6.5) than devices placed at the heterozygous group (57.5 ± 11.6). Once more, the results were significantly different (P< 0.05). iii Results of the experiments revealed that Runx2 activity specifically in chondrocytes is required for a normal healing response to implants and that loss of one copy can alter the process of bone formation in a mouse model.
Recommended Citation
Rivera, Jaime Rodrigo, "Bone Formation Around Implants In Adult Transgenic Mice With Selective Runx2-Ii Deficiency" (2008). All ETDs from UAB. 3626.
https://digitalcommons.library.uab.edu/etd-collection/3626