Introduction:

Orthodontic treatment is responsible for gingival overgrowth (GO), a clinical condition characterized by pathological, diffuse, or localized growth of gingival tissue. Excessive accumulation of the extracellular matrix, including type I collagen, contributes to the pathological manifestations of GO. The objective of this study is to identify and describe the distribution of type I collagen in the gingival tissue of patients with GO because of fixed orthodontics.

Materials and Methods:

A descriptive study that analyzed the gingival tissues of subjects diagnosed with GO with orthodontic (test, n = 5) and periodontally healthy individuals (control, n = 5). The samples were obtained by gingivectomy. All the biopsies were fixed, embedded in paraffin, and cut and analyzed using picrosirius red/fast green staining, in order to distinguish the collagen fiber. By means of an immunohistochemical reaction, type I collagen was identified with a monoclonal antibody.

Results:

A hyperplastic epithelial tissue was identified with an evident increase in epithelial processes and connective tissue with abundant bundles of collagen fiber, mainly in the basal lamina and the underlying area in patients with GO because of orthodontic treatment. Type I collagen fiber in the tissues of patients with orthodontic GO were thick and disorganized in appearance with intense immunohistochemical staining, compared to the fibers of the control group.

Conclusions:

The increase in collagen fibers, particularly type I collagen, is a histological finding that characterizes patients with GO because of fixed orthodontics.

        · abstract in Spanish | Portuguese     · text in Spanish     · Spanish ( pdf )