Damak Yarıklarının İn Situ Doku Mühendisliği ile Onarımı: Alveolar Yarık Hayvan Modeli Oluşturulması ve Farklı Rejimlerde Biyobozunur Doku Iskeleleri ile Onarımı
Özet
In this study, the tricalcium phosphate polymer, a tissue scaffold known for its direct effects on tissue healing, and that is used commonly in bone defect models, was upgraded by adding collagen by the Hacettepe University Department of Bioengineering. This study aims to compare this new enriched tissue scaffold with the standard tissue scaffold (ɛ-kaprolakton) and autogeneous bone grafting, which is the gold standard in alveolar cleft treatment. In this study, 64 animals were used, 48 for histological and radiological analyses, and 16 for gene expression studies. Regardless of groups, a bone defect of critical size (7x4x3 mm) was created, as formerly defined. The subjects in 8 different groups were examined in 2 different time intervals (4 groupx2, n= 48). In the negative control group, alveolar defect was created on the subjects, and no further procedures were performed. In the positive control group (the autograft group), the autograft harvested from the iliac bone of the subject was implanted on the deficient area. In the other two groups, the alveolar bone defects were reconstructed by the newly developed Collagen/ β-TCP and the standard ɛ-kaprolakton tissue scaffolds. The specimens gathered from the defective areas of the sacrificed animals were examined first macroscopically in the 1st and 4th months, then by micro-CT, in which the volume of the new bone tissue was calculated. When the micro-CT images were examined with respect to the volume of the newly formed bone, the autogenous graft group was found to have the best ossification on both histological and radiological analyses. Also, the amount of ossification on the 4th month was detected to be more than the amount of ossification on the 1st month. When the results of the Collagen/β-TCP group, the main component of this study, was analyzed, the increase in the rate of ossification was found to be statistically important, compared to the Standard tissue sacaffold group. This was also the group whose ossification results were closest to the autogenous graft group. For the histological examination, the specimens were stained with hematoxyllin, eosin and mason trichrome stains; and the blocks were examined for healing of the defect, new bone formation and tissue response. These data show that there is a quick healing in the autogenous graft group in the 1st and 4th months, and the Collagen/β-TCP group had the closest results in regard to the new bone formation. Likewise, in the gene expression studies, the best groups were the autograft and Collagen/β-TCP group. In conclusion, these data show that although the gold standard for treatment is autogenous bone grafting, tissue scaffolds developed through bioengineering can be regarded as an alternative when cost, donor area morbidity, and length of hospital stay are considered.