Peri-implantitis represents a heterogeneous mixed infection that includes periodontopathic microorganisms, uncultivable asaccharolytic anaerobic Gram-positive rods and other uncultivable Gram-negative rods, and, rarely, opportunistic microorganisms such as enteric rods and Staphylococcus aureus. Sequencing methods that evaluate the entire microbiome improve identification of microorganisms associated with peri-implantitis.

Aim The aim of the present study was to establish the association between the presence of oral and uro‐vaginal microorganisms in the placental membrane and preterm delivery (PTD), the premature rupture of membranes (PRM), and the clinical signs of intra‐amniotic infection. Methods Eighty‐four women with PTD and 127 women with delivery at term were assessed for the PRM, clinical signs of intra‐amniotic infection, and the presence of periodontitis. Twenty‐seven microorganisms were identified in the placental tissue using nested polymerase chain reaction (PCR). Porphyromonas gingivalis (P. gingivalis) was quantified by droplet digital PCR. Results The prevalence of microorganisms was 9.47% (20/211). P. gingivalis was the most prevalent (12/211, 5.68%). Mycoplasma hominis, Ureaplasma urealyticum, Staphylococcus spp, and Fusobacterium nucleatum were isolated at a very low frequency in the placenta. Candida albicans was associated with PTD (P = 0.027). Periodontitis was associated with clinical signs of infection (odds ratio [OR] = 3.8, 95% confidence interval [CI]: 1.28‐13.5) and with PTD (OR = 1.99; 95% CI: 1.07‐3.72). Conclusion The presence of P. gingivalis in the placenta was not associated with perinatal complications. Detecting microorganisms in the placenta by nested PCR is not relevant, as it has a poor association with clinical variables that establish the diagnosis of chorioamnionitis. However, periodontitis was associated with the clinical signs of intra‐amniotic infection and PTD.

Periodontal condition is a factor independent of other important risk factors for a perinatal adverse outcome and PRM. Prevention of periodontal disease should be included in preconception and prenatal care programs.

The microbiome modulates inflammation at the fetal maternal interface on both term and preterm labor. Inflammophilic oral bacteria, such as Porphyromonas gingivalis, as well as urogenital microorganisms (UGM) could translocate to the placenta and activate immune mechanisms in decidual tissue that is associated with adverse pregnancy outcomes (APO). This study establishes the associations between the presence of microbes in the placenta and placental cytokine patterns in women who presented APO, e.g., low birth weight (LBW), preterm premature rupture of membranes (PPROM), preterm birth (PTB) and other clinical signs related to Chorioamnionitis (CA). A total of 40 pregnant women were included in the study and divided into five groups according to placental infection (PI) and APO, as follows: (1) women without PI and without APO (n = 17), (2) women with P. gingivalis-related PI and APO (n = 5), (3) women with P. gingivalis-related PI and without APO (n = 4), (4) women with PI related to UGM and APO (n = 5) and (5) women without PI with APO (n = 9). Obstetric, clinical periodontal status evaluation, and subgingival plaque sampling were performed at the time of delivery. Placental levels of interleukin IL-1β, IL-6, IL-10, IL-15, IL-17A, IL-17F, IL-21, IL-12p70, tumor necrosis factor-α (TNF-α), monocyte chemoattractant protein-1 α (MCP-1α), granzyme B, and interferon-γ (IFN-γ) were determined using a multiplex flow cytometry assay. All patients showed a predominant Th-1 cytokine profile related to labor, characterized by IFN-γ overexpression. The analysis by groups suggests that Th-1 profile was trending to maintain cytotoxic cell activity by the expression of IL-15 and granzyme B, except for the group with P. gingivalis-related PI and APO, which exhibited a reduction of IL-10 and IL-17F cytokines (p < 0.05) and a Th-1 profile favoring macrophage activation by MCP-1 production (p < 0.05). This study confirms a pro-inflammatory pattern associated with labor, characterized by a Th-1 profile and the activity of cytotoxic cells, which is enhanced by PI with UGM. However, PI associated with P. gingivalis suggests a switch where the Th-1 profile favors an inflammatory response mediated by MCP-1 and macrophage activity as a mechanistic explanation of its possible relationship with adverse outcomes in pregnancy.

Objectives Culturable and unculturable microorganisms have been associated with periodontitis. Their differential proportions and composition have not been evaluated by their severity and complexity defined by stages in the 2018 AAP-EEP classification. Methods One hundred eighty subgingival biofilm samples were collected in Spain and Colombia from subjects categorized as health/gingivitis: periodontitis stages I/II periodontitis stages III/IV. Target culturable microorganisms (Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Tannerella forsythia, Treponema denticola, and Eubacterium nodatum) and target unculturable microorganisms (Filifactor alocis, Eubacterium saphenum, Eubacterium brachy, Desulfobulbus oralis) were evaluated by quantitative PCR analysis. In addition, their differences and association with periodontal status were analyzed by ANCOVA and logistic regression models once adjusted to age, current smoking, and country. Results P. gingivalis was significantly associated with periodontitis stages I/II, OR 2.44 (CI 95% 1.08–5.47) and stages III/V, OR 6.43 (CI 95% 2.43–16.9). T forsythia, OR 7.53 (CI 95% 2.07–27.4); D. oralis, OR 5.99 (CI 95% 2.71–13.23); F. alocis, OR 10.9 (CI 95% 4.56–23.2); E. brachy, 3.57 (CI 95% 1.40–9.11); and E. saphenum, 4.85 (CI 95% 1.99–11.7) were significantly associated only with stages III/IV periodontitis. P. gingivalis evidenced significant differences with the increase in the severity of the periodontal lesion: 2.97 colony forming unit (CFU)/μL (CI 95% 2.32–3.54) health/gingivitis, and 4.66 CFU/μL (CI 95% 4.03–5.30) and 5.90 CFU/μL (CI 95% 5.20–6.48) in stages I/II and III/IV respectively (p < 0.0001). Unculturable microorganisms only evidenced differences in concentration in stages III/IV compared with health-gingivitis (p ≤ 0.001). Conclusion Culturable and unculturable are strongly associated with stages III/IV periodontitis. Classic culturable microorganisms are more sensitive to differentiate between stages of periodontitis in the quantitative analysis. Clinical relevance Future interventional studies of periodontal disease should include Filifactor alocis, Eubacterium saphenum, Eubacterium brachy, and Desulfobulbus oralis as possible markers of therapy response and as indicators of progressive disease.