Synthesis and biocompatibility of an experimental glass ionomer cement prepared by a non-hydrolytic sol-gel method

Abstract

The aims of this study were to demonstrate the synthesis of an experimental glass ionomer cement (GIC) by the non-hydrolytic sol-gel method and to evaluate its biocompatibility in comparison to a conventional glass ionomer cement (Vidrion R). Four polyethylene tubes containing the tested cements were implanted in the dorsal region of 15 rats, as follows: GI - experimental GIC and GII - conventional GIC. The external tube walls was considered the control group (CG). The rats were sacrificed 7, 21 and 42 days after implant placement for histopathological analysis. A four-point (I-IV) scoring system was used to graduate the inflammatory reaction. Regarding the experimental GIC sintherization, thermogravimetric and x-ray diffraction analysis demonstrated vitreous material formation at 110oC by the sol-gel method. For biocompatibility test, results showed a moderate chronic inflammatory reaction for GI (III), severe for GII (IV) and mild for CG (II) at 7 days. After 21 days, GI presented a mild reaction (II); GII, moderate (III) and CG, mild (II). At 42 days, GI showed a mild/absent inflammatory reaction (II to I), similar to GII (II to I). CG presented absence of chronic inflammatory reaction (I). It was concluded that the experimental GIC presented mild/absent tissue reaction after 42 days, being biocompatible when tested in the connective tissue of rats.

Histological analysis of biocompatibility of ionomer cements with an acid-base reaction

“…Generally speaking, the expressive response in the initial events, such as the response to irritation, tended to diminish in subsequent and final periods. 9,[28][29] It can be inferred that the clinical use of materials with better biologic behavior must be encouraged, insofar as orthodontic ionomers in flowable form, used for cementation, frequently come into contact with gingival and subgingival tissues, and metal ions and intrinsic acids of the GIC composition may be released both during the setting process and in the degradation of these cements over time. [13][14] …”

Morphological and immunohistochemical analysis of the biocompatibility of resin‐modified cements

“…The specimens were prepared on glass slides by means of routing Hematoxylin and Eosin (HE) staining, and afterwards evaluated under an optical microscope Leica DM500 ® (Leica Microsystems Vertrieb GmbH, Wetzlar, Germany), at 100×, 200×, and 400× magnifications. According to the methodology proposed by Santos et al () and Garcia et al (), the following histopathological parameters were evaluated: intensity of inflammatory infiltrate and reaction of multinucleated giant cells, with scores considered being: 0—scarce; 1—light (when scarcely present, or in very small groups); 2—moderate (when densely present, or in some groups); and 3—intense (when found in the entire field, or present in large numbers, indicating a high degree of severity). The histopathological evaluation was made by a single, previously calibrated evaluator (Kappa = 0.8) and blind for the evaluation of groups.…”

Evaluation in vivo of biocompatibility of differents resin-modified cements for bonding orthodontic bands

“…According to the methodology proposed by studies (Garcia et al 2010, Santos et al 2010, the histological parameters assessed were: Inflammatory infiltrate intensity; edema; necrosis; multinucleated giant cell reaction, granulation reaction; young fibroblasts and collagenization, with the following scores being considered: 0 -scarce; 1-light (when scarcely present, or in very …”