Prediction of Future Caries in 1-Year-Old Children via the Salivary Microbiome.

Dental caries is the most common chronic disease in children that causes negative effects on their health, development, and well-being. Early preventive interventions are key to reduce early childhood caries prevalence. An efficient strategy is to provide risk-based targeted prevention; however, this requires an accurate caries risk predictor, which is still lacking for infants before caries onset. We aimed to develop a caries prediction model based on the salivary microbiome of caries-free 1-y-old children. Using a nested case-control design within a prospective cohort study, we selected 30 children based on their caries status at 1-y follow-up (at 2 y old): 10 children who remained caries-free, 10 who developed noncavitated caries, and 10 who developed cavitated caries. Saliva samples collected at baseline before caries onset were analyzed through 16S rRNA gene sequencing. The results of ß diversity analysis showed a significant difference in salivary microbiome composition between children who remained caries-free and those who developed cavitated caries at 2 y old (analysis of similarities, Benjamini-Hochberg corrected, P = 0.042). The relative abundance of Prevotella nanceiensis, Leptotrichia sp. HMT 215, Prevotella melaninogenica, and Campylobacter concisus in children who remained caries-free was significantly higher than in children who developed cavitated caries (Wilcoxon rank sum test, P = 0.024, 0.040, 0.049, and 0.049, respectively). These taxa were also identified as biomarkers for children who remained caries-free (linear discriminant analysis effect size, linear discriminant analysis score = 3.69, 3.74, 3.53, and 3.46). A machine learning model based on these 4 species distinguished between 1-y-old children who did and did not develop cavitated caries at 2 y old, with an accuracy of 80%, sensitivity of 80%, and specificity of 80% (area under the curve, 0.8; 95% CI, 44.4 to 97.5). Our findings suggest that these salivary microbial biomarkers could assist in predicting future caries in caries-free 1-y-old children and, upon validation, are promising for development into an adjunctive tool for caries risk prediction for prevention and monitoring.

Oral Health Birth Cohort Studies: Achievements, Challenges, and Potential.

Birth cohorts are those among observational studies that provide understanding of the natural history and causality of diseases since early in life. Discussions during an International Association for Dental Research symposium in London, United Kingdom, in 2018, followed by a workshop in Bangkok, Thailand, in 2019, concluded that there are few birth cohort studies that consider oral health and that a broader discussion on similarities and differences among those studies would be valuable. This article aims to 1) bring together available long-term data of oral health birth cohort studies from the low, middle, and high-income countries worldwide and 2) describe similarities and differences among these studies. This work comprises 15 studies from all 5 continents. The most studied dental conditions and exposures are identified; findings are summarized; and methodological differences and similarities among studies are presented. Methodological strengths and weaknesses are also highlighted. Findings are summarized in 1) the negative impact of detrimental socioeconomic status on oral health changes over time, 2) the role of unfavorable patterns of dental visiting on oral health, 3) associations between general and oral health, 4) nutritional and dietary effects on oral health, and 5) intergenerational influences on oral health. Dental caries and dental visiting patterns have been recorded in all studies. Sources of fluoride exposure have been documented in most of the more recent studies. Despite some methodological differences in the way that the exposures and outcomes were measured, some findings are consistent. Predictive models have been used with caries risk tools, periodontitis occurrence, and permanent dentition orthodontic treatment need. The next steps of the group's work are as follows: 1) establishing a consortium of oral health birth cohort studies, 2) conducting a scoping review, 3) exploring opportunities for pooled data analyses to answer pressing research questions, and 4) promoting and enabling the development of the next generation of oral health researchers.

Cross-Sectional Analysis of Alcohol Intake and Serum Antibodies to Oral Microorganisms.

The objective of this study was to evaluate the relation between alcohol intake and groups of periodontal antibody titers among individuals with normal glucose tolerance (NGT), prediabetes and diabetes. This was a cross-sectional analysis of the National Health and Nutrition Examination Survey III (NHANES III) 1988-1994 data, among individuals 40 y and older with information on alcohol intake and serum immunoglobulin G (IgG) antibody data against 19 oral microorganisms. Participants were excluded if they did not have teeth, reported that they were taking insulin, or having gestational diabetes. The sample size for this analysis was 3,219. Periodontal antibodies were grouped into four clusters using cluster analysis: Orange-Red, Red-Green, Yellow- Orange, and Orange-Blue. Cluster scores were computed for each individual by summing z-scores of standardized log-transformed IgG titers of antibodies against periodontal microorganisms making up each respective cluster. Each cluster score was modeled as an outcome. Alcohol consumption was assessed in g/day using self-reported number of days of drinking in the past 12 mo and the average number of drinks consumed per day on days when they drank. Overall, alcohol intake was positively associated with periodontal antibodies of the Orange-Red cluster (P. melaninogenica, P. intermedia, P. nigrescens, and P. gingivalis), and inversely associated with the Yellow-Orange cluster (S. intermedius, S. oralis, S. mutans, F. nucleatum, P. micra, C. ochracea) after multivariable adjustment. The association between alcohol intake and the Orange-Red cluster was strongest among individuals with diabetes; this relation was seen among individuals with and without periodontal damage. The Orange-Red cluster was positively associated with periodontal damage among individuals with diabetes. Alcohol intake was not associated with any antibody cluster among individuals with NGT or prediabetes. The effect of alcohol intake on periodontal disease may be greater among individuals with diabetes but this finding needs to be confirmed in prospective studies. Knowledge Transfer Statement: The results of this study can be used by clinicians when treating patients with periodontal disease and diabetes.

Oral health and ventilator-associated pneumonia among critically ill patients: a prospective study.

OBJECTIVE: To evaluate the association between oral health and ventilator-associated pneumonia (VAP) among critically ill patients. METHODS: A prospective cohort study was conducted among 162 critically ill patients newly intubated and treated with mechanical ventilator in one tertiary hospital in Thailand. Oral health status was assessed using Oral Health Assessment Tool (OHAT), Plaque Index (PI), and number of teeth. VAP, defined as Clinical Pulmonary Infection Score >6, was assessed on Day 4 after intubation. Hazard ratios and 95% confidence intervals (CIs) were calculated using Cox proportional hazards regression adjusted for confounders. RESULTS: Critically ill patients had deteriorating oral health status after intubation. Early-onset VAP developed in 69 patients (42.6%), with VAP incidence of 117 episodes per 1000 ventilator-days. Moderately unhealthy and unhealthy oral conditions based on OHAT scores were associated with a 2.92-fold (95% CI: 1.26-6.74) and 3.22-fold (95% CI: 1.34-7.76) increased risk of VAP. Patients with moderate-to-very poor oral hygiene assessed by PI had increased VAP risk of 1.66-folds (95% CI: 1.001-2.75). The number of teeth was not associated with VAP development. CONCLUSIONS: There is a strong association between poor oral health and increased risk for early-onset VAP. Routine oral care possibly prevents VAP development among critically ill patients treated with mechanical ventilator.

Salivary Lysozyme in Relation to Dental Caries among Thai Preschoolers.

AIM: The objective of this study was to analyze salivary lysozyme levels and activities in Thai preschoolers with different dental caries status. STUDY DESIGN: Unstimulated saliva samples were collected from 64 preschoolers, divided into a caries free group (n = 32) and a severe early childhood caries (S-ECC) group (n = 32). RESULTS: Both groups were similar regarding gender, age, dental caries status, salivary flow rate, and salivary protein concentrations. No differences were also in the caregivers' characteristics, oral health behaviors, and feeding habits. Only professional fluoride application was less frequently found in the S-ECC group (p < 0.03). Western blotting and lysoplate assays revealed that salivary lysozyme levels and activities were significantly increased in the S-ECC group compared with the caries free group (p< 0.001; p = 0.008, respectively). CONCLUSION: The up-regulated expression of salivary lysozyme and the increased lysozyme activity in S-ECC preschoolers suggests a possible connection between salivary lysozyme and oral immunity in response to early childhood dental caries.

Micronutrients and oral clefts: a case-control study.

Little is known about oral clefts in developing countries. We aimed to identify micronutrient-related and environmental risk factors for oral clefts in Thailand. We tested hypotheses that maternal exposure during the periconceptional period to multivitamins or liver consumption would decrease cleft lip with or without cleft palate (CL ± P) risk and that menstrual regulation supplements would increase CL ± P risk. We conducted a multisite hospital-based case-control study in Thailand. We enrolled cases with CL ± P and 2 live births as controls at birth from the same hospital. Mothers completed a questionnaire. Conditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Eighty-six cases and 172 controls were enrolled. Mothers who took a vitamin (adjusted OR, 0.39; 95% CI: 0.16, 0.94) or ate liver (adjusted OR, 0.26; 95% CI: 0.12, 0.57) were less likely than those who did not to have an affected child. Mothers who took a menstrual regulation supplement were more likely than mothers who did not to have an affected child. Findings did not differ for infants with a family history of other anomalies or with isolated CL ± P. If replicated, our finding that liver decreases CL ± P risk could offer a low-cost primary prevention strategy.

Red bacterial complex is associated with the severity of chronic periodontitis in a Thai population.

BACKGROUND: The distribution of periodontal pathogens differs in various geographic locations and racial/ethnic groups. This study investigated the microbiological features of chronic periodontitis (CP) patients in Thailand. METHODS: Subgingival plaque samples from 20 non-periodontitis subjects, 20 patients with mild CP, and 20 patients with moderate to severe CP were examined using polymerase chain reaction (PCR) to identify Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, and Aggregatibacter actinomycetemcomitans. RESULTS: In the moderate to severe CP patients, there was high prevalence of P. gingivalis (95%), T. forsythia (95%), T. denticola (80%), as well as the red complex (coexistence of all three species at the same lesion) (75%). A. actinomycetemcomitans was detected in only 35% of the patients in this study group. P. gingivalis was detected in as high as 45% of the non-periodontitis controls. CP and disease severity were significantly related to the presence of T. forsythia together with T. denticola and the red complex. The red complex was not found in any non-periodontitis site. CONCLUSION: Red complex bacteria were predominant periodontal pathogens of the moderate to severe form of CP in this Thai population. The presence of T. forsythia together with T. denticola, and the red complex species at the same site were significantly associated with the disease severity.

Clinical and microbiological effects of subgingival irrigation with Streblus asper leaf extract in chronic periodontitis.

OBJECTIVE: To determine the clinical and microbiological effects of subgingival irrigation of Streblus asper leaf extract (SAE) solution as an adjunct to scaling and root planing (SRP) in chronic periodontitis patients. METHODOLOGY: Forty-two subjects were included and treated with SRP at baseline (week 0), followed by subgingival irrigation with saline (control group, n=21) or SAE (test group, n=21) solution (80 mg/ml) at weeks zero, one, two, three, and four. Clinical parameters, including gingival index (GI), plaque index (PI), probing depth (PD), and relative attachment level (RAL) were measured at weeks zero, six, and 12. Microbiological parameters were measured at weeks zero, one, two, three, four, six, and 12. RESULTS: The SAE solution significantly reduced the GI compared with saline solution (p < 0.01). However, a reduction in PI, PD, and RAL was noted for both groups, with no statistically significant intergroup differences. The reduction in the number ofA. actinomycetemcomitans and/or P. gingivalis was maintained throughout the study period after subgingival irrigation with SAE solution, while an initial reduction and subsequent rebound were observed after saline irrigation. However, the mean number and mean percentages of sites with 10 times the reduction in number of these bacteria were not significantly different between the two groups. CONCLUSION: Subgingival irrigation with SAE solution as an adjunct to SRP is effective at reducing gingival inflammation, but not PD, RAL, and the number of A. actinomycetemcomitans and/or P. gingivalis.

Inhibitory effect of Streblus asper leaf-extract on adhesion of Candida albicans to denture acrylic.

This in vitro study aimed at determining the effects of various sublethal concentrations of Streblus asper leaf ethanolic extract (SAE) on adherence of Candida albicans to acrylic surface. A colorimetric tetrazolium assay using (2,3)-bis (2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)-carbonyl]-2H-tetrazolium hydroxide was used to make the quantitative determination. The SAE at a concentration equivalent to nystatin (6.24microg/ml) pinpointed the minimal exposure time of SAE in suppressing candidal adhesion to acrylic. Adhesion of Candida albicans to acrylic was determined after exposure to SAE for 1, 15, 30, 60, 120 and 180min. The minimum concentration of SAE that significantly reduced adherence (P<0.05) after a 4-h exposure was 31.25mg/ml. In addition, a significant reduction (P<0.01) of candidal adhesion to acrylic occurred after a 1min exposure to 62.5mg/ml of SAE. Pre-treatment of yeast with 62.5mg/ml of SAE for 1h before adhesion assay significant reduced the adherence as 20.54% compared to the untreated control, whereas the same treatment with acrylic strips did not show any effect. These findings indicate that exposure of Candida albicans to sublethal concentrations of SAE results in a reduction in the ability of the yeasts to adhere to denture acrylic, possibly preventative of denture stomatitis.

The usefulness of using Ramfjord teeth in predicting periodontal status of a Tanzanian adult population.

OBJECTIVES: The only partial mouth index that has been validated against full-mouth examinations in the East African population is the CPITN (Community Periodontal Index of Treatment Needs). Since the Ramfjord index can potentially shorten the examination time by almost half, we evaluated Ramfjord teeth in predicting full-mouth periodontal status of an adult population in Tanzania. MATERIAL AND METHODS: Pocket depth was measured for 192 consecutive patients aged from 15 to 77 years (36 years old on average); 86 (45%) females referred to the Department of Restorative Dentistry, Muhimbili National Hospital, Tanzania between January 1997 and December 1999, and the mean pocket depth for full-mouth and Ramfjord teeth was calculated. RESULTS: The correlation between the mean pocket depth calculated from the full-mouth and Ramfjord teeth was 0.96. The beta coefficient for the mean pocket depth measured by Ramfjord teeth to predict the full-mouth mean was 0.94, and was not affected by adjustment for age, missing teeth or sex. CONCLUSION: This overall high agreement between Ramjford teeth and full-mouth periodontal pocket situation confirms the epidemiological validity of Ramfjord's dental sample in our setting.

Alcohol consumption increases periodontitis risk.

Alcohol consumption impairs neutrophil, macrophage, and T-cell functions, increasing the likelihood of infections. We examined the association between alcohol consumption and periodontitis, prospectively, among 39,461 male health professionals aged 40 to 75 years and free of periodontitis at the start of follow-up. Alcohol intake was assessed at baseline and updated every 4 years by a food-frequency questionnaire. Periodontal disease status was self-reported and validated against radiographs. Multivariate analysis was adjusted for age, smoking, diabetes, body-mass index, physical activity, time period, and caloric intake. During 406,160 person-years of follow-up, there were 2125 cases of periodontitis. Compared with non-drinkers, the relative risk (95% confidence interval) among men reporting usual alcohol intake of 0.1-4.9 g/day was 1.24 (1.09, 1.42); 5.0 to 14.9 g/day, 1.18 (1.04, 1.35); 15 to 29.9 g/day, 1.18 (1.01, 1.38); and > 30 g/day, 1.27 (1.08, 1.49). The results suggest that alcohol consumption is an independent modifiable risk factor for periodontitis.

Factors associated with delay in the diagnosis of oral cancer.

Early detection and treatment improve the prognosis for oral cancer. Delays from the onset of symptoms to clinical diagnosis are common. Our aim is to identify factors associated with this delay. Between 1995 and 1998, we interviewed 105 consecutive patients with histologically confirmed oral cancer in Greece. If 21 or more days elapsed from the time the patient noticed major symptoms to a definitive diagnosis, we called it a delay (52% of cases). We used logistic and linear regression to estimate odds ratios of delayed diagnosis and to identify correlates of length of delay, respectively. Former smokers had a 4.3 times greater risk of delayed diagnosis compared with current smokers (95% confidence interval: 1.1-17.1). The length of delay was greater among single patients, non-smokers, or those with stage IV tumors. Clinicians should be advised that delay in the diagnosis of oral cancer occurs frequently, even in individuals who do not smoke heavily.

Thickness of palatal masticatory mucosa associated with age.

BACKGROUND: The palatal masticatory mucosa is widely used as a donor material in periodontal plastic surgery. However, there are relatively few studies investigating the volume or thickness of the palatal mucosa. The purpose of this study was to determine the thickness of palatal masticatory mucosa in Asian subjects aged 14 to 59 years by a direct clinical technique. The associations of age and gender with the thickness of palatal mucosa were also examined. METHODS: Sixty-two systemically and periodontally healthy Asians (31 males; 31 females; age range 14 to 59 years) participated in this study. The younger age group (age 14 to 21 years) consisted of 32 subjects with a mean age of 16.8 years, whereas the older age group (age 30 to 59 years) consisted of 30 subjects with a mean age of 38.7 years. A bone-sounding method using a periodontal probe with minimal anesthesia and a prepared clear acrylic stent were utilized to assess the thickness of palatal mucosa at 15 measurement sites defined according to the gingival margin and mid-palatal line. Multiple linear regression analysis was performed to examine the associations of age and gender with the mean mucosal thickness at the subject level. The Wilcoxon test was used to determine the difference in mucosal thickness between the 2 age groups, and between gender at each measurement point. RESULTS: The mean thickness of palatal masticatory mucosa ranged from 2.0 to 3.7 mm. The younger age group had significantly thinner mucosa (mean 2.8 +/- 0.3 mm) than the older age group (mean 3.1 +/- 0.3 mm). Females had thinner mucosa than males in the same age group, but the difference was not statistically significant. Overall, the thickness of palatal mucosa increased from the canine to second molar areas and in the sites furthest from the gingival margin towards the mid-palate (with the exception of the first molar area, where significantly decreased thickness was observed). CONCLUSIONS: Within the limits of the present study, the canine and premolar areas appear to be the most appropriate donor site for grafting procedures in both young and adult individuals. The subepithelial connective tissue graft procedure can be considered as a treatment modality in young patients, since a sufficient volume of donor tissue can be obtained from the hard palate area. Other factors that may influence the thickness of palatal mucosa such as racial and genetic factors and body weight need to be further investigated.

Paan without tobacco: an independent risk factor for oral cancer.

Oral cancer is the second most common cancer in women and the third most common in men in Pakistan. Tobacco is smoked and chewed extensively in Pakistan. Paan is a quid of piper betel leaf that contains areca nut, lime, condiment, sweeteners, and sometimes tobacco, which is also used extensively. We did this study to clarify the independent association of paan and oral cancer. Between July 1996 and March 1998, we recruited biopsy-proven, primary cases of oral squamous-cell carcinoma, from 3 tertiary teaching centers in Karachi, Pakistan, and controls pair-matched for age, gender, hospital and time of occurrence, excluding persons with a past or present history of any malignancy. There were 79 cases and 149 controls. Approximately 68% of the cases were men, 49 years old on average, the youngest being 22 years old and the eldest 80. People with oral submucous fibrosis were 19.1 times more likely to develop oral cancer than those without it, after adjusting for other risk factors. People using paan without tobacco were 9.9 times, those using paan with tobacco 8.4 times, more likely to develop oral cancer as compared with non-users, after adjustment for other covariates. This study identifies an independent effect of paan without tobacco in the causation of oral cancer. Its findings may be of significance in South Asian communities where paan is used, and among health-care providers who treat persons from South Asia.