Faculty Bibliography

This study compared the anatomical features of the tongue in nine pairs of twins - six monozygotic and three dizygotic. The aim of the project was to determine if tongues, like any other anatomical structure, could be used to reliably predict relatedness given that tongue shape, presentation and surface can be influenced by environment. Using the method of forced choice, 30 subjects were asked to match the photographs of tongues from twins. Our data indicate that, based on visual assessment, monozygotic twins have highly similar tongues (60% matches); similarly, dizygotic twins were matched 31% of the time, which is a higher probability than would be expected from random selection. This study should help identify baseline and control data in future behavioral studies of taste, which has a genetic basis

The purpose of this study was to provide a univariate and multivariate analysis of genomic microbial data and salivary mass-spectrometry proteomic profiles for dental caries outcomes. In order to determine potential useful biomarkers for dental caries, a multivariate classification analysis was employed to build predictive models capable of classifying microbial and salivary sample profiles with generalization performance. We used high-throughput methodologies including multiplexed microbial arrays and SELDI-TOF-MS profiling to characterize the oral flora and salivary proteome in 204 children aged 1-8 years (n = 118 caries-free, n = 86 caries-active). The population received little dental care and was deemed at high risk for childhood caries. Findings of the study indicate that models incorporating both microbial and proteomic data are superior to models of only microbial or salivary data alone. Comparison of results for the combined and independent data suggests that the combination of proteomic and microbial sources is beneficial for the classification accuracy and that combined data lead to improved predictive models for caries-active and caries-free patients. The best predictive model had a 6% test error, >92% sensitivity, and >95% specificity. These findings suggest that further characterization of the oral microflora and the salivary proteome associated with health and caries may provide clinically useful biomarkers to better predict future caries experience.

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION: Hemostatic management for periodontal treatments in patients on oral antithrombotic therapy: a retrospective study. Morimoto Y, Niwa H, Minematsu K. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2009;108(6):889-96. REVIEWER: Walter A. Bretz, DDS, PhD PURPOSE/QUESTION: The authors attempted to evaluate hemostatic management of periodontal treatment in patients on oral antithrombotic therapy. SOURCE OF FUNDING: Information not available TYPE OF STUDY/DESIGN: Retrospective case series LEVEL OF EVIDENCE: Level 3: Other evidence STRENGTH OF RECOMMENDATION GRADE: Not applicable

OBJECTIVES: The aim of this study was to analyze the periodontal parameters of patients with chronic renal failure. MATERIAL AND METHODS: The periodontal status of 16 Brazilian patients aged 29 to 53 (41.7 +/- 7.2) years with chronic renal failure (CRF) and another matched group of 14 healthy controls with periodontitis was assessed clinically and microbiologically. Probing pocket depth (PPD), gingival recession (GR), dental plaque index (PLI), gingival index (GI), and dental calculus index (CI) were the clinical parameters recorded for the entire dentition (at least 19 teeth), while the anaerobic periodontopathogen colonization in four sites with the highest PPD was evaluated using the BANA test ("PerioScan"; Oral B). RESULTS: The results for the CRF group and control group, respectively were: PPD: 1.77 +/- 0.32 and 2.65 +/- 0.53; GR: 0.58 +/- 0.56 and 0.51 +/- 0.36; PLI: 1.64 +/- 0.56 and 1.24 +/- 0.67; GI: 0.64 +/- 0.42 and 0.93 +/- 0.50; CI: 1.17 +/- 0.54 and 0.87 +/- 0.52. Comparison between groups using the "t" test revealed a significantly increased PPD (p<0.001) in the control group. Comparison of the other clinicial parameters by the Mann-Whitney test showed differences only for PLI, which was significantly higher (p<0.05) in the CRF group. Spearman's test applied to each group showed a positive correlation among all clinical parameters, except for GR (p<0.05). None of the groups showed any correlation between GR and GI, while a significant negative correlation between GR and PPD was observed for the CRF group. The percentage of BANA-positive sites was 35.9% for the CRF group and 35.7% for the control group. The BANA test correlated positively with PPD only in the control group and with GR only in the CRF group. CONCLUSIONS: In spite of a higher PLI and dense anaerobic microbial population even in shallow PPD, patients with CRF exhibited better periodontal conditions than periodontitis patients, which is an evidence of altered response to local irritants.

Purpose: The etiology of RA remains unknown, but genetic and environmental factors have been implicated. An infectious trigger has been sought but conventional microbiologic techniques have been uninformative. The human intestine contains a dense, diverse and poorly characterized (>=80% uncultured) bacterial population whose collective genome (microbiome) is >=100 times larger than its human host. We (DRL) have recently shown in mice that gut-residing bacteria drive autoimmune arthritis via Th17 cell activation (Immunity 2010). Multiple lines of investigation also suggest a link between RA and oral microbes. Methods: As part of an NIH ARRA grant, the NYU Microbiome Center for Rheumatology and Autoimmunity was established to study gut and oral microbiota in RA and related conditions. A cross-sectional study and prospective proof-of-concept antibiotic intervention trial are ongoing. Fecal samples are collected, periodontal status assessed and oral samples obtained by subgingival biofilm collection. To date, oral/intestinal microbiomes have been analyzed in 8 RA patients, 3 psoriatic arthritis (PsA) patients and 9 healthy controls. Periodontal status was characterized in 30 RA, 4 PsA and 8 controls. DNA was purified and variable 16s rRNA gene regions amplified. PCR products were pyrosequenced (454 Life Sciences), and DNA sequences compared to the RDP and BLAST catalogs. rDNA-based phylogenetic trees were created, and the UNIFRAC metric used to compare bacterial communities across individuals. Sera from all subjects were evaluated for anti-citrullinated peptide antibodies (ACPA). Results: Prevotellaceae family was significantly overrepresented in fecal microbiota from ACPA+ RA patients (range 13%-85%; mean=38%) vs ACPA-individuals (mean=4.3%); p=0.003. One ACPA+ healthy individual and 1 ACPA+ PsA patient shared similar microbiomes with ACPA+ RA. Subgingival microbiomes in patients with new-onset drug-naive RA exhibited overabundance of the Spirochetaceae/Prevotellaceae/Porphyromonaceae families (mean=53%) compared to chronic-active RA and healthy controls (mean=18.5%). Periodontal assessment revealed 78% of examined sites bled upon probing in RA patients (mean age 39; 73% female), significantly more than controls (38% PsA, 12% healthy; p<0.001 vs RA); 66% of RA patients also presented with moderate periodontitis compared to PsA (25%) and controls (12%). Conclusions: This is the first study using high-throughput technologies to assess oral and intestinal microbiota in RA. Our data corroborate prior reports demonstrating an underappreciated high prevalence of periodontal disease at a young age in patients with RA. Moreover, our preliminary data suggest that ACPA generation may be associated with larger populations of Prevotellaceae in both oral and intestinal microbiomes. In response to such altered microbial flora, certain predisposed individuals may develop auto-inflammatory disease, through mechanisms that may include the generation of cyclic citrullinated peptides or Th17 cell activation in the intestinal mucosa. Thus, the oral and intestinal microbiota merit further investigation as potential triggers for autoimmunity and clinical RA

The aims of this study are (1) to describe issues related to recruitment of mothers participating in a clinical trial of transmission of mutans streptococci (MS) from mother to child in Bauru, Brazil and (2) to perform cross-cultural and temporal comparisons of levels of infection of the MS in mothers of Bauru. A total of 1422 mothers were visited at their domiciles. Cutoff levels for the MS were established at >/=10(5) CFU/mL saliva. The main reason for a mother not enrolling was not being highly infected by the MS, yet 76% of mothers presented with levels >/=10(5) CFU/mL saliva. Recent studies in industrialized countries showed a negative coefficient for linear tests indicating significant decline overtime in the levels of MS in mothers. Intercountry comparisons for mothers' salivary levels of the MS with the Bauru study as the reference revealed significant differences with studies conducted in the last two decades

The purpose of this study was to evaluate the effect of chlorhexidine on the proteolytic activity of carious coronal and root dentin collected from patients. Sound dentin from freshly extracted human teeth was used as a control. Dentin fragments were mixed with a synthetic substrate for proteolytic enzymes (N-benzoyl-DL-arginine-naphthylamide--BANA) and the suspensions mixed with either 0.12% chlorhexidine digluconate or distilled water. These mixtures were incubated for 18 h at 37 degrees C, color was developed by the addition of 0.1% Fast Garnet and their optical density was recorded spectrophotometrically. BANA hydrolysis measured by the optical density of incubated specimens was detected in all tested groups, but was significantly higher for carious than for sound dentin (p < 0.05). The proteolytic activity was reduced for carious coronal and root dentin by chlorhexidine (p < 0.05; 50 and 30%, respectively). Chlorhexidine also reduced the proteolytic activity in sound root dentin (p < 0.05; 20%). Conversely, changes in the proteolytic activity of sound coronal dentin were not observed in the presence of chlorhexidine. The reduction in proteolytic activity by chlorhexidine was significantly higher in carious coronal dentin than in carious root dentin (p < 0.05). In conclusion, part of the effect of chlorhexidine in controlling caries progression in humans may be due to a decrease in the proteolytic activity of carious coronal and root dentin. Because of the prolonged incubation time in the present study, similar results may be obtained clinically with prolonged dentin exposure to chlorhexidine, e.g. chlorhexidine-containing varnishes.

BACKGROUND: The purpose of this study was to assess the effects of dental flossing on the microbial composition of interproximal plaque samples in matched twins. METHODS: The study was a two-treatment, examiner-masked, randomized, parallel-group, controlled study. Fifty-one twin pairs between 12 and 21 years of age were randomized to a 2-week supervised and unsupervised treatment regimen consisting of tongue brushing and toothbrushing or tongue brushing and toothbrushing plus flossing. The reverse-capture checkerboard hybridization assay was used to assess levels (abundance) of 26 microbial species in interproximal plaque samples collected from six sites per subject. An integrative computational predictive model estimated average changes in microbial abundance patterns of selected bacterial species from baseline to 2 weeks by comparing treatment groups. RESULTS: After the 2-week study period, putative periodontal pathogens and cariogenic bacteria were overabundant in the group that did not floss compared to the group that performed flossing. Those included Treponema denticola, Porphyromonas gingivalis, Tannerella forsythia (previously T. forsythensis), Prevotella intermedia, Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), and Streptococcus mutans. Microbial species that are not consistent with the development of periodontal disease or dental caries were overabundant in the group that did floss compared to the non-flossing group. CONCLUSION: In a well-matched twin cohort, tooth and tongue brushing plus flossing significantly decreased the abundance of microbial species associated with periodontal disease and dental caries after a 2-week program