Identification of bacterial species in subgingival plaque as a risk factor for periodontitis in peri-menopausal and post-menopausal women using or not using hormone replacement therapy (HRT)

Background: The objective of this study was to assess the implications of the menopause in patients treated or not with HRT on their oral health, with particular reference to quantitative and qualitative changes of the major periodontal pathogens which may lead to homeostatic alterations in the balance of the microbiota in favour of some species most frequently involved in the etio-pathogenesis of periodontal diseases. In order to assess this, the effects of HRT on oral microbiota has been taken into account, using as a comparison the microbiota of postmenopausal women, who did not undergo HRT. Methods: We examined 64 patients aged between 45 and 80 years (mean age 59 years) in menopause, who accessed the Institute of Pathology, Obstetrics and Gynaecology of the University Hospital Vittorio Emanuele “G. Rodolico” of Catania, 60 of whom were diagnosed with chronic periodontitis. For each patient, samples were collected from the subgingival plaque in 4 sites in the proximity of 1st and 2nd molar, using sterile paper points, two times (after 2 years). Samples of sub-gingival plaque of patients were analysed using assays based on the PCR technique, aimed to the qualitative and quantitative detection of the occurrence of conserved sequences of the 16S rRNA portion of 12 of the major periodontal pathogens. Results: The main organisms detected in first and second sampling were Campylobacter rectus, Prevotella nigrescens, Treponema denticola and Veillonella parvula. C. rectus has been identified in almost 80% of patients during the first sampling and in 31 of 34 patients in the second sampling, including 13 patients with HRT. P. nigrescens in the first specimen was identified in 28 of 34 patients, while in the second sample in 30 of them, 15 of which under HRT. T. denticola was present in the first specimen in 25 patients, while in the second sample in 32 of 34, 10 of which under HRT. V. parvula was found in 28 of 34 patients at the first sampling and in 31 patients at the second, 17 of which were under HRT. Conclusion: The use of HRT in this study did not reduce the prevalence of the reported oral symptoms and did not significantly affect the frequency of bacteria isolation. Anyway, further studies with long-term follow-up would be needed to better assess the effect of HRT on the parameters of oral health.