The Impact of Smoking on Gingiva: a Histopathological Study

Smoking can be associated with the decreasing gingival blood flow and epithelial changes. The aim of this study was to evaluate the histopathological changes of gingival epithelium and connective tissue in smokers. The study was case-control. Sixty male patients (28 smokers and 32 nonsmokers) suffering chronic periodontitis were participated in the study. Periodontal parameters consisting the gingival (GI) and periodontal (PI) indexes were registered. Tissue samples were taken during flap surgery. The hemotoxylin and eosin stained slides were assessed for blood vessel density, inflammatory cells infiltration and epithelial changes. The histopathological findings were compared between smokers and nonsmokers. Data analyzed using t-test and chi-square tests. Smokers had lower GI (1.35 ± 0.48) and higher PI (2.87±0.68) than nonsmokers (2.72 ±0.31 and 1.87±0.25, respectively). The mean count of blood vessels with ≤ 0.5µ diameter was 18.78±10.06 and 5.90±2.93 in smokers, nonsmokers, respectively. The mean inflammatory cells infiltration in smokers, and nonsmokers were 0.89±1.03 and 70±0.46 that showed significant difference between two groups (P= 0.001, SD=1.21). The difference of epithelial hyperkeratosis, atrophy and acanthosis was not different in smokers and nonsmokers. Loss of normal epithelium pattern comprising of bulbous rete ridges, loss of polarity and increased parabasal cells was seen in 23(82.14%) of smokers and 2(6.25%) of nonsmokers. Despite the normal appearance of gingiva in smokers, smoking increasing the epithelial changes resemble to early phases of dysplasia and decreasing inflammatory reaction.