Microbial profile of placentas from Tanzanian mothers with adverse pregnancy outcomes and periodontitis.

AIM: To investigate microbial profiles in placentas from a population of East African mothers with and without adverse pregnancy outcomes and with regard to their periodontal status. MATERIAL AND METHODS: Thirty-six placentas from pregnant women from Tanzania were classified into three groups according to both pregnancy outcome and the mother's periodontal health. The microbial composition in each group was then compared using 16S rRNA metagenomics. Additionally, placenta specimens were analyzed histologically for chorioamnionitis by a single pathologist blinded to the clinical data. RESULTS: The greatest differences were observed in the group of mothers with periodontitis. The microbial load was low in all three groups of mothers. Periodontitis had a notable influence on the structure of the placental microbiota. Three phyla and 44 genera were associated with periodontitis, whereas only the Tenericutes phylum was associated with the adverse pregnancy variable. Streptococcaceae and Mycoplasmataceae families were associated with both periodontitis and adverse pregnancy outcomes. Finally, although the differences for chorioamnionitis were not significant, this intra-amniotic infection was more frequent in the placentas from mothers with periodontitis. CONCLUSIONS: Our findings suggest that bacteria from the oral cavity may involve the feto-placental unit, and that periodontitis may be a modulating factor of the microbial community present in this niche.

Periodontal and dental conditions of a school population in a volcanic region of Tanzania with highly fluoridated community drinking water.

INTRODUCTION: Dental fluorosis is endemic in the Rift Valley in Africa, especially around volcanic areas, due to the high fluoride content in daily drinking water. OBJECTIVE: This study evaluates the oral health status and types of occlusion in a school population, and to assess the possible association between dental fluorosis and other pathologies such as decay, gingivitis and periodontitis. MATERIAL AND METHODS: An observational study of 581 individuals recruited from a public secondary school in Arusha, Northern Tanzania was undertaken. The indices used were: the Silness & Löe Plaque Index, the Community Periodontal Index and the Decayed/Missing/Filled index. Descriptive statistical analyses were performed and a chi-square test was used to assess the associations between independent variables. RESULTS: Almost all the school children evaluated (96.73%) presented Angle class I dental occlusion, and 75.22% presented some degree of dental fluorosis. Most of the population (511, 87.95%) showed bleeding on probing. A moderate/high degree of some dental pathology (DMF score) was recorded in 14.46%. The association between dental fluorosis, gingival bleeding and tooth decay indicated a higher concentration of pathology in groups with more severe fluorosis (p<0.05). CONCLUSION: In this large population sample, both tooth decay and gingivitis were significantly associated with moderate or severe dental fluorosis.