James A. Katancik

The Human Microbiome Project used rigorous good clinical practice standards to complete comprehensive body site sampling in healthy 18‐ to 40‐yr‐old adults, creating an unparalleled reference set of microbiome specimens. To ensure that specimens represented minimally perturbed microbiomes, we first screened potential participants using exclusion criteria based on health history, including the presence of systemic diseases ( e.g. , hypertension, cancer, or immunodeficiency or autoimmune disorders), use of potential immunomodulators, and recent use of antibiotics or probiotics. Subsequent physical examinations excluded individuals based on body mass index (BMI), cutaneous lesions, and oral health. We screened 554 individuals to enroll 300 (149 men and 151 women, mean age 26 yr, mean BMI 24 kg/m 2 , 20.0% racial minority, and 10.7% Hispanic). We obtained specimens from the oral cavity, nares, skin, gastrointestinal tract, and vagina (15 specimens from men and 18 from women). The study evaluated longitudinal changes in an individual's microbiome by sampling 279 participants twice (mean 212 d after the first sampling; range 30‐359 d) and 100 individuals 3 times (mean 72 d after the second sampling; range 30‐224 d). This sampling strategy yielded 11,174 primary specimens, from which 12,479 DNA samples were submitted to 4 centers for metagenomic sequencing. Our clinical design and well‐defined reference cohort has laid a foundation for microbiome research.—Aagaard, K., Petrosino, J., Keitel, W., Watson, M., Katancik, J., Garcia, N., Patel, S., Cutting, M., Madden, T., Hamilton, H., Harris, E., Gevers, D., Simone, G., McInnes, P., Versalovic, J. The Human Microbiome Project strategy for comprehensive sampling of the human microbiome and why it matters. FASEB J. 27, 1012–1022 (2013). www.fasebj.org

IMPORTANCE: Chronic periodontitis, a destructive inflammatory disorder of the supporting structures of the teeth, is prevalent in patients with diabetes. Limited evidence suggests that periodontal therapy may improve glycemic control. OBJECTIVE: To determine if nonsurgical periodontal treatment reduces levels of glycated hemoglobin (HbA1c) in persons with type 2 diabetes and moderate to advanced chronic periodontitis. DESIGN, SETTING, AND PARTICIPANTS: The Diabetes and Periodontal Therapy Trial (DPTT), a 6-month, single-masked, multicenter, randomized clinical trial. Participants had type 2 diabetes, were taking stable doses of medications, had HbA1c levels between 7% and less than 9%, and untreated chronic periodontitis. Five hundred fourteen participants were enrolled between November 2009 and March 2012 from diabetes and dental clinics and communities affiliated with 5 academic medical centers. INTERVENTIONS: The treatment group (n = 257) received scaling and root planing plus chlorhexidine oral rinse at baseline and supportive periodontal therapy at 3 and 6 months. The control group (n = 257) received no treatment for 6 months. MAIN OUTCOMES AND MEASURES: Difference in change in HbA1c level from baseline between groups at 6 months. Secondary outcomes included changes in probing pocket depths, clinical attachment loss, bleeding on probing, gingival index, fasting glucose level, and Homeostasis Model Assessment (HOMA2) score. RESULTS: Enrollment was stopped early because of futility. At 6 months, mean HbA1c levels in the periodontal therapy group increased 0.17% (SD, 1.0), compared with 0.11% (SD, 1.0) in the control group, with no significant difference between groups based on a linear regression model adjusting for clinical site (mean difference, -0.05% [95% CI, -0.23% to 0.12%]; P = .55). Periodontal measures improved in the treatment group compared with the control group at 6 months, with adjusted between-group differences of 0.28 mm (95% CI, 0.18 to 0.37) for probing depth, 0.25 mm (95% CI, 0.14 to 0.36) for clinical attachment loss, 13.1% (95% CI, 8.1% to 18.1%) for bleeding on probing, and 0.27 (95% CI, 0.17 to 0.37) for gingival index (P < .001 for all). CONCLUSIONS AND RELEVANCE: Nonsurgical periodontal therapy did not improve glycemic control in patients with type 2 diabetes and moderate to advanced chronic periodontitis. These findings do not support the use of nonsurgical periodontal treatment in patients with diabetes for the purpose of lowering levels of HbA1c. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00997178.

BACKGROUND: The objective of this study was to examine the relationship between airway obstruction and periodontal disease. METHODS: Participants were a subset of 860 community- dwelling, well functioning elderly (aged 70 to 79, blacks and whites, males and females) selected from 2,732 participants enrolled in the Health, Aging, and Body Composition Study (Health ABC). The periodontal evaluations occurred over years 2 and 3 of the study and included four indices of periodontal health: plaque index (PI), gingival index (GI), probing depth (PD), and loss of attachment (LOA). The pulmonary evaluation took place in year 1: conducted according to American Thoracic Society criteria, based on the forced expiratory volume/forced vital capacity (FEV1/FVC) ratio and then using the percent of predicted FEV1 to categorize severity. RESULTS: GI (P = 0.023) and LOA (P = 0.009) were significantly better in participants with normal pulmonary function compared to those with airway obstruction after adjusting for age, race, gender, and field center. When stratified by smoking status and after adjusting for age, race, gender, center, and pack-years, there was a significant association between periodontal health and airway obstruction in former smokers. Within this group, those with normal pulmonary function had significantly better GI (P = 0.036) and LOA (P = 0.0003) scores than those with airway obstruction. All periodontal indices were elevated in smokers regardless of pulmonary status; however, the current smoker group was too small to detect a periodontitis effect. CONCLUSION: While the present cross-sectional study cannot provide direct inference of cause and effect, it does reveal a significant association between periodontal disease and airway obstruction, particularly in former smokers.

PURPOSE: The purpose of this retrospective chart-review study was to compare the early success rate and the crestal bone changes of dental implants in patients taking oral bisphosphonates at the time of implant placement to those of patients who had never taken bisphosphonates. MATERIALS AND METHODS: A retrospective chart review of 100 women (153 implants) taking oral bisphosphonates at the time of implant placement (test group) and 100 women (132 implants) who had never taken bisphosphonates (control group) was performed to examine overall implant success at the time of stage-two surgery. Radiographic images, which were available for 73 patients in each group and were taken at the time of implant placement and at stage-two surgery, were analyzed to assess and compare crestal bone changes around the implants. RESULTS: There was no significant difference between groups in the success rates of dental implants at stage-two surgery (test 93.5%, control 95.5%). The change in crestal bone height was statistically significant from the time of placement to stage-two surgery within both groups but was not significantly different between groups (means ± standard deviations: test, 0.66 ± 0.70 mm; control: 0.80 ± 0.65 mm). CONCLUSIONS: In this study, the use of oral bisphosphonates at the time of implant placement and during healing did not affect early implant success rates or crestal bone changes up to the time of stage-two surgery. In addition, the implant location and the duration of drug therapy at the time of placement were not significant factors in the success rate or bony changes. These conclusions must be viewed in the context of the limitations of the retrospective study design and should be confirmed in longer, more rigorously designed studies.