Effect of topical ozonetherapy on gingival wound healing in pigs: histological and immuno-histochemical analysis

Abstract

Objectives: In this study, the effects of ozonetherapy on secondary wound healing were evaluated histologically and immuno-histochemically.

Material and methods: Material and Methods: 8 healthy pigs were used in this study. Six wounds with 10 mm in diameter were created through the punch technique on the palatinal gingiva of each pig. Ozone gas was applied on only 3 wounds (test group) and the remaining 3 were left to natural healing (control group). Biopsy samples were taken from one of the wounds in each group on the third day, from another wound of each group on the seventh day, and from another one on the tenth day. Routine histological analysis and immuno-histochemical staining were performed to investigate transforming growth factor-beta (TGF-β) and (VEGF) expressions.

Results: Results: No statistical difference was found between the test and control groups in terms of collagen fibers, epithelial formation and inflammation scores. A VEGF expression found in the test group was statistically higher than control group samples taken on the 3rd and 7th day. There was no statistical difference between the test and control groups in terms of TGF-β expression on any of the sampling days.

Conclusions: Conclusion: The topical application of ozone gas could be effective in the early stages of wound healing by increasing the amount of VEGF expression. Clinical Relevance: Topical application of ozone gas may be effective in the early stages of oral wound healing.

Figure 1. Creation of wounds on the palatal region

Figure 2. Application of ozone gas to test wounds

Figure 3. Histological results; Day 3 (A, D), Day 7 (B, E), Day 10 (C, F); test (A, B, C) ve Control (D, E, F) group. Appearance of wound area; (HE; x20) (wa: wound area; e: exudate; n: neutrophil; ep: epithelium; gt: granulation tissue; smat: submucosal adipose tissue; pe: proliferated epithelium)

Figure 4. Inflammation scores of test and control groups on days 3, 7, 10 (p>0.05)

Figure 5. VEGF; Day 3 (A, D), Day 7 (B, E), Day 10 (C, F) and control (C, D) test (A, B, C) and Control (D, E, F) group, VEGF expression. (AEC; A, C, D, F: x200; B, E: x100 (ve: vascular endothelium; gt: granulation tissue; pe: proliferated epithelium; arrows: VEGF positive staining)

Figure 6. VEGF staining intensity between the test and control groups

Figure 7. TGF-β; Day 3 (A,D), Day 7 (B, E), Day 10 (C, F) and control (C,D) test (A, B, C) and Control (D, E, F) group, TGF-β expression. (AEC; A, C, D, F: x200; B, E: x100) (e: exudate; arrows: TGF-β positive staining)

Figure 8. TGF-β staining intensity of the test and control groups