Topical Oxygenation Improves Microvascularity in a Human Ex Vivo Palatal Tissue Model: A Histological Analysis

TL;DR

This study found that topical oxygen therapy may improve microvascularity in oral tissues without causing damage.

Contribution

The study is among the first to histologically evaluate the effects of topical oxygen therapy on oral tissues.

Findings

TOT increased average vessel area, number, and caliber compared to the control group.

Microvessel density was higher in the TOT-treated samples.

TOT did not cause tissue damage and was associated with type I collagen prevalence.

Abstract

Background: Several therapies involving the use of oxygen have been developed; however, the literature to date has poorly addressed the effects of Topical Oxygen Therapy (TOT) on oral tissues. The aim of the present pilot study was to histologically evaluate the response to TOT in epithelial–connective samples harvested from the palate. Methods: In eight patients selected for a free gingival graft (FGG) procedure, the lateral portions of the graft were randomly assigned to receive TOT (test) or no treatment (control). Both the portions were stained with hematoxylin–eosin for the evaluation of histomorphological changes and with Picrosirius for the study of collagen. Immunohistochemical staining was performed with antibodies for the characterization of the inflammatory infiltrate and neoangiogenesis. Results: The analysis failed to show morphological variations in both groups, demonstrating that there was no tissue damage due to TOT. The prevalence of type I collagen in both samples supported this finding. Immune cells were present in low levels and mainly consisted of CD3+ T lymphocytes. The histomorphometric analysis showed an increased average vessel area (7607.95 μm2 ± 3983.24 vs. 4038.42 μm2 ± 1823.52), an increased number and caliber of vessels (49.82 ± 20.55 vs. 32.35 ± 16.64), and a higher microvessel density (7.89 ± 3.25 vessels/0.26 mm2 vs. 5.13 ± 2.63 vessels/0.26 mm2) in the test group. Conclusions: Although further investigations are needed, TOT could improve and speed up oral wound healing through the local condition of hyperoxia.

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