Comparative evaluation of expression of VEGF (vascular endothelial growth factors) in periodontal tissues of healthy, chronic and aggressive periodontitis patients: an immunohistochemical study

Abstract

Periodontitis is a chronic inflammatory disease of the vascularized supporting tissues of the teeth. Angiogenesis (neovascularization) is the budding of new capillaries and is thought to be an essential process in the development of chronic inflammatory diseases. Inflamed tissues (such as gingiva coincident in periodontal disease) have evidence of enhanced expression of inflammatory mediators, many of which can promote angiogenesis. Of the various cytokines and growth factors that are involved in angiogenesis, the most potent agent that acts specifically on vascular epithelium is Vascular Endothelial Growth Factor. Even though angiogenesis is a prominent feature of both inflammation and healing, information about its role in periodontal lesions is limited. Hence the aim of the present study was the immunohistochemical evaluation of the expression of VEGF in the gingival tissues of chronic and aggressive periodontitis patients compared to the healthy controls. The present study was carried out in a total of 45 subjects with age range of 18-55 years, reporting to the Department of Periodontology, Rajarajeswari Dental College and Hospital, Bangalore. Gingival tissue samples were collected from all the 45 subjects and categorized into three groups based on their clinical findings as follows: Group 1 (Healthy), Group II (Chronic Periodontitis), Group III (Aggressive Periodontitis). Following sample collection, immunohistochemical staining of tissues was carried out and evaluation was done to compare the grades of expression of VEGF in the three groups. The expression of VEGF in blood vessels was also quantitatively evaluated. The results were statistically analyzed using Kruskal Wallis ANOVA and Mann Whitney test. There was a statistically significant higher expression of VEGF in both chronic periodontitis and aggressive periodontitis group as compared to the control group. Aggressive periodontitis cases showed higher grades of expression of VEGF compared to the chronic periodontitis cases and healthy controls. However, the difference in expression of VEGF was not statistically significant between the two forms of periodontitis. The presence of VEGF in both chronic and aggressive periodontitis clearly indicates the potent role played by VEGF as an inflammatory agent in the initiation and progression of periodontal diseases. Thus, VEGF might be used as a potential vascular marker for the assessment of severity and inflammatory status in periodontal disease.