Quantitative analysis of the cellular components of the fibrous tissue matrix surrounding ALCAP, HA, and TCP bioceramics using adult male rats as a model.

This investigation was specifically an attempt to correlate the thickness of this fibrous capsule and the various histological components that are seen in the fibrous capsule surrounding ALCAP, HA, and TCP ceramics at the S/C and I/P implantation sites in order to further elucidate the mechanisms of tissue-implant interaction. Eighteen male albino rats were randomly divided into three experimental groups (n = 5/group) and one control (n = 3). Animals in Groups I, II, and III were implanted with the ALCAP, HA, and TCP ceramics, respectively. Animals in Group IV were not implanted and acted as the control group. At 90 days post-implantation, the animals in all groups were euthanized and the fibrous tissue surrounding the ceramic devices and internal organs were harvested. After routine histological processing, sections of tissue was stained with hematoxylin and eosin and evaluated using light microscopy. Analysis of the data revealed the following: 1) The presence of macrophages, neutrophils, fibroblasts, vascularity, and thickness of the fibrous tissue matrix was found to be statistically different among the subcutaneously implanted ceramic groups (ANOVA, p < 0.01). 2) The presence of collagen (S/C) is not statistically different among the three ceramic groups (ANOVA, p = 0.76). 3) The presence of macrophages, neutrophils, fibroblasts, and collagen comprising the fibrous tissue surrounding the ALCAP, HA, and TCP ceramics (I/P), was found to be statistically different (ANOVA, p < 0.01). 4) Vascularity and thickness of the fibrous tissue surrounding the three I/P ceramics were not found to be statistically different among the three ceramic groups (ANOVA, p > 0.05).