Prevalence of oral Epstein-Barr virus and Porphyromonas gingivalis and their association with periodontal inflamed surface area: A cross-sectional study.

We previously reported that oral herpesviruses, such as Epstein-Barr virus (EBV), are associated with periodontitis. However, the relationship between oral EBV or dual oral EBV and Porphyromonas gingivalis infections and periodontal inflammation severity remains unclear. We conducted this study to determine the relationship between oral EBV and P gingivalis prevalence and the periodontal inflamed surface area (PISA) in middle-aged and older adults. We analyzed 205 patients (median age, 70 years) who visited Hiroshima University Hospital. Tongue swab samples were used to investigate the presence of EBV and P gingivalis DNA using real-time PCR. Probing pocket depth and bleeding on probing were measured at 6 sites per tooth. PISA scores were calculated based on the results of probing pocket depth and bleeding on probing. Propensity scores were calculated via logistic regression analysis of 8 clinical factors: age, sex, smoking status, remaining teeth, denture use, hypertension, diabetes, and hyperlipidemia. EBV DNA was present in 41 of the 205 participants (20.0%). Thirty-seven EBV-positive or -negative participants in 74 matched pairs after propensity-score matching were examined via univariate analysis. EBV-positive participants exhibited higher plaque control record scores and PISAs than did EBV-negative participants. EBV DNA was significantly associated with plaque control record scores and PISA (both P = .04). Of the 205 participants, 111 were positive for P gingivalis (54.1%). Nineteen participants (9.3%) were infected with both oral EBV and P gingivalis. Logistic regression analysis revealed that dual infection with EBV and P gingivalis was significantly associated with diabetes (odds ratio = 3.37, 95% confidence interval: 1.13-10.1; P = .03). Oral EBV prevalence is associated with oral hygiene and the spread of inflamed periodontal tissue. Diabetes may be a risk factor for dual infection with oral EBV and P gingivalis.

The Associations of Periodontopathic Bacteria and Oral Candida with Periodontal Inflamed Surface Area in Older Adults Receiving Supportive Periodontal Therapy.

The periodontal inflamed surface area (PISA) has been proposed for assessment of the total periodontal inflammatory status in people with periodontitis. This study was performed to investigate the associations of periodontopathic bacteria and candida with PISA in older people. We enrolled 100 patients aged ≥ 60 years who visited Hiroshima University Hospital. PISA and periodontal epithelial surface area (PESA) were calculated in each patient. Oral rinse samples were collected for DNA extraction. Periodontopathic bacteria and candida were detected by polymerase chain reaction. The mean values of PISA and PESA were significantly greater in T.forsythia-positive patients than in T.forsythia-negative patients. T.forsythia/C. albicans double-positive patients exhibited significantly greater PISA values than did non-double-positive patients. Additionally, PISA values were significantly greater in T. forsythia//T. denticola/C. albicans triple-positive patients than in T. forsythia//T. denticola/C. albicans non-triple-positive patients (p = 0.02). Propensity score-matching was performed between periodontopathic bacteria-positive and -negative patients using propensity scores generated from clinical factors. Importantly, T.forsythia/T. denticola double-positive patients exhibited significantly greater PISA values than non-double-positive patients among 72 propensity score-matched patients. Our preliminary results highlight the importance of the presence of T.forsythia and T. denticola for periodontal inflammation severity in older Japanese people.

Association of oral Epstein-Barr virus with periodontal health in Japanese adults.

Previous studies have demonstrated that oral Epstein-Barr virus (EBV) is associated with periodontitis. However, the relationship between periodontitis and oral EBV has not been fully elucidated by reducing the effects of confounding factors. The aim of the present study was to clarify the association between oral Epstein-Barr virus (EBV) and oral health status among middle-aged and older Japanese individuals. A total of 124 patients (46 males and 78 females; mean age, 69.2 years; age range, 35-90 years) who visited Hiroshima University Hospital between October 2018 and December 2019 were recruited into the present study. EBV DNA positivity was determined in 124 oral rinse samples using quantitative PCR. Periodontal disease-related bacteria were also detected by PCR analysis. EBV DNA was determined as positive in 16 of the 124 enrolled patients (12.9%). No significant difference was identified between EBV DNA and clinical factors (sex, age, remaining teeth, denture use, smoking or medical history). Of the 38 patients with periodontal pockets ≥6 mm, 10 were EBV DNA positive (26.3%). There was a significant association between EBV DNA positivity and probing depth (P=0.01). Additionally, a significant association was identified between bleeding on probing (BOP) and EBV DNA positivity (P=0.03). To investigate the relationship between EBV and periodontal health status, propensity score-matching was determined between participants without ≥4 mm periodontal pockets and BOP (participants with good periodontal health) and those with ≥4 mm periodontal pockets, BOP or both (participants with poor periodontal health). A total of 35 matched pairs were identified among the patients. Patients with poor periodontal health exhibited a higher EBV DNA positivity rate (25.7%) than those with good periodontal health (0.0%). Additionally, there was a significant association between EBV DNA positivity and periodontal health status (P=0.001). T. denticola-positive participants exhibited a higher EBV DNA positivity rate than negative participants (17.6 vs. 9.6%). However, there was no significant difference. The results indicated that oral EBV may be markedly associated with periodontitis in middle-aged and older Japanese individuals.

Association of oral HPV16 infection with periodontal inflammation and the oral microbiome in older women.

The present preliminary study aimed to investigate the association between oral human papillomavirus type 16 (HPV16) DNA prevalence and periodontal inflammation in older women. The association between oral HPV16 infection and oral health status has not been fully elucidated in older Japanese women. The present study investigated older women aged ≥60 years who visited Hiroshima University Hospital. The present study excluded subjects with clinical factors affecting HPV infection, such as current smoking, oral cancer and pre-malignant lesions, and immunodeficiency. Finally, 46 female patients (mean age, 74.6 years) were analyzed. Quantitative PCR analysis was performed to detect HPV16 DNA in oral rinse samples. A total of 4 participants (8.7%) were HPV16 DNA positive. There was a significant association between the HPV16 DNA positivity rate and bleeding on probing (P=0.03). Additionally, Prevotella intermedia positive cases exhibited a significantly higher HPV16 DNA positivity rate than negative cases (33.3 vs 3.8%). Furthermore, analysis of 16S ribosomal RNA in bacterial flora was performed to examine microbiome diversity in participants with ≥6 mm periodontal pockets and bleeding on probing. Importantly, the average percentage of Porphyromonas was significantly higher in HPV16 DNA positive cases compared with in HPV16 DNA negative cases (5.57 vs. 1.44%). By contrast, the average percentage of Veillonella was significantly lower in HPV16 DNA positive cases than in HPV16 DNA negative cases (2.43 vs. 8.51%). Prevotella was also lower in HPV16 DNA positive cases than in HPV16 DNA negative cases (4.0 vs. 8.23%). These results indicated that people with both deep periodontal pocket inflammation and oral HPV16 infection may not have Prevotella- or Veillonella-dominant oral microbiomes, and their microbiomes may exhibit their own distinctive characteristics. In conclusion, the results suggested that oral HPV16 infection may be associated with periodontal inflammation in older Japanese women. Further research is required to clarify the detailed association between oral HPV infection and the oral microbiome.

High Rate of Oral Candida Detection in Dependent Japanese Older People.

The aim of this study was to clarify the association between oral Candida detection and the dependency status of older people. This study included 31 older people aged ≥70 years who had a certified need for long-term care or support and received care in a local day care center; it also included 27 independent older patients aged ≥70 years who visited Hiroshima University Hospital. Oral Candida was detected by a polymerase chain reaction using swab samples from the tongue surface. Oral moisture was significantly reduced in dependent older people, compared with independent older people (p = 0.003). There was a weak negative relationship between numbers of bacteria and levels of oral moisture (Spearman's rank correlation coefficient; R = -0.29, p = 0.01). Dependent older people exhibited a significantly higher rate of Candida albicans detection (35.5%) compared with independent older people (11.1%). Dependent older people also exhibited a higher rate of concurrent detection of both C. albicans and Candida glabrata (32.3%) compared with independent older people (11.1%), but this difference was not statistically significant. Thus, dependent older people may be more susceptible to oral C. albicans infection, compared with independent older people. Good oral hygiene is necessary to prevent oral Candida infection in dependent older people.

Detection of oral bacteria on the tongue dorsum using PCR amplification of 16S ribosomal RNA and its association with systemic disease in middle-aged and elderly patients.

The association between oral health and systemic disease is recognized in the literature. The present study aimed to clarify the association between oral bacteria on the tongue dorsum and factors associated with oral health and systemic disease in middle-aged and elderly patients. The association between bacterial numbers, oral health status and systemic disease was preliminarily investigated in 70 patients (mean age, 69.5 years; range, 45-92 years) who visited the Department of Oral Health, Hiroshima University Hospital (Hiroshima, Japan). The bacterial 16S ribosomal RNA gene was employed to quantitate bacterial numbers using real-time polymerase chain reaction (PCR). PCR was also performed to detect the DNA of periodontal disease-related bacteria. Oral bacterial numbers were marginally negatively correlated with moisture levels on the tongue surface [Spearman's rank correlation coefficient (R)=-0.131, P=0.28). Subjects with bleeding on probing (BOP) or a ≥4 mm probing depth (PD) exhibited higher Porphyromonas gingivalis (P. gingivalis)-positive rates (50.0 and 51.1%, respectively) than those without BOP or a <4 mm PD (39.5 and 30.4%, respectively). Subjects with medical histories of hypertension, diabetes, stroke and heart disease exhibited a trend toward higher P. gingivalis-positive rates than those without such disorders. These findings indicated that the tongue moisture level may be associated with bacterial numbers on the tongue surface, while P. gingivalis on the tongue surface may be associated with systemic and periodontal diseases. Further investigation in a larger number of participants is necessary to clarify the correlation between bacterial numbers and systemic disease.