Biomaterials and Sol-Gel Process: A Methodology for the Preparation of Functional Materials - Biomaterials Science and Engineering - page 22

b
Fig. 22. SEM micrographs recorded for the glass ionomer cements. (a) experimental and (b)
conventional

a

The micrographs revealed that the surface the conventional cement presents lower
homogeneity, compared to the experimental cement. The better homogeneity of the
experimental cement is due to the homogeneity of particle size, which promotes the same
physical-chemistry properties all over the cement surface.
The biocompatible test was carried out on the basis of the response obtained with the tissue
stimulated by the experimental cement and compared to that achieved with the
conventional cement. These responses were analyzed by means of morphological and
morphometric analyses of the reaction caused by these cements in the subcutaneous tissue
of rats. Polyethylene tubes were obtained according to the methodology used by Campos-
Pinto et al. [89]. To this end, an urethral catheter with an internal diameter of 0.8 mm was
sectioned sequentially at 10 mm intervals. After sectioning, one of the tube ends was sealed
with cyanoacrylate ester gel (Super Bonder, Aachen, Germany), to avoid extravasation of the
material to be tested. The obtained tubes were placed in a metal box and autoclaved at
120°C for 20 min. [90].
The data obtained for all the histopathological events assessed in each period of study are
presented in Table 3.

Histopathological
Events

7 days 21 days 42 days

GGI GGII CCG GGI GGII CCG GGI GGII CCG

Polymorphonuclear +++ +++ ++ ++ ++ ++ -- -- --

Mononuclear +++ ++++ ++ ++ ++ ++ -- -- --

Fibroblasts +++ +++ ++ ++ ++ ++ ++ ++ ++

Blood vessels +++ ++++ +++ +++ ++ ++ ++ ++ --

Macrophage ++ +++ ++ -- ++ -- -- -- --

Giant inflammatory
cells

++ ++ ++ -- -- -- -- -- --

Score: (-) absent; (+) slight; (++) moderate; (+++) intense.
CG - control group; GI - experimental cement; GII - conventional cement.
Table 3. Summary of the data obtained for the histopathological events observed in each
group at the different periods of study.