The Oral-Gut Axis: Periodontal Diseases and Gastrointestinal Disorders.

One of the prospective sequelae of periodontal disease (PD), chronic inflammation of the oral mucosa, is the development of inflammatory gastrointestinal (GI) disorders due to the amplification and expansion of the oral pathobionts. In addition, chronic inflammatory diseases related to the GI tract, which include inflammatory bowel disease (IBD), can lead to malignancy susceptibility in the colon of both animals and humans. Recent studies suggest that dysbiosis of the oral microbiota can alter the microbial composition in relative abundance or diversity of the distal gut, leading to the progression of digestive carcinogenesis. The link between PD and specific GI disorders is also closely associated with the migration and colonization of periodontal pathogens and the subsequent microbe-reactive T cell induction within the intestines. In this review, an in-depth examination of this relationship and the accessibility of different mouse models of IBD and PD may shed light on the current dogma. As such, oral microbiota dysbiosis involving specific bacteria, including Fusobacterium nucleatum and Porphyromonas gingivalis, can ultimately lead to gut malignancies. Further understanding the precise mechanism(s) of the oral-gut microbial axis in PD, IBD, and colorectal cancer pathogenesis will be pivotal in diagnosis, prognosis, and future treatment.

Status of North American Graduate Programs in Periodontics Providing Laser Education and Clinical Training: A Cross-Sectional Survey.

The aim of this cross-sectional study was to evaluate the status of laser use and training in the U.S. and Canadian graduate periodontology programs. A survey questionnaire was sent electronically to 55 periodontology program directors in North America. The questions focused on laser implementation, types of lasers used, for which procedures lasers were used, and level of education/clinical training provided to residents. Data were analyzed using descriptive statistics and Fisher's exact test. Twenty-two directors responded (40%). Most programs (86%) used lasers and 89% used a diode laser. Laser treatment was the most used for periimplantitis (84%). Fifteen programs (79%) provided didactic and clinical training, with 47% programs giving 4-12 h of didactic training. In 53% of programs, residents completed 4 to10 procedures. Only 29% of programs had residents who had received a certification in lasers, with most (80%) programs requiring between 1-9 cases for certification. Of the participants not providing laser training, the major barrier was indicated as being "expense", with 68.7% reporting plans to implement laser education. Conclusions: Most graduate periodontics programs were providing laser training and treatment. There was great variability regarding the training methods, specifically in number of dedicated laser courses, time allocated for laser training, and prerequisites for laser certification.

Laser Treatment of Peri-Implantitis: A Systematic Review of Radiographic Outcomes.

(1) Background: This systematic review aimed to evaluate the effects of laser therapy on radiographic bone level (RBL) changes in peri-implantitis defects. (2) Methods: A literature search with defined inclusion criteria was performed. PubMed, Web of Science, Cochrane Library, and Google Scholar were searched through September 2020. The evaluated primary outcomes were RBL changes. In studies that reported RBL data, corresponding secondary clinical outcomes were probing depth (PD), bleeding on probing (BOP), and clinical attachment level (CAL). (3) Results: Thirteen articles were selected for data extraction and risk of bias assessment. Eight studies showed evidence of RBL gain in the laser groups compared to baseline, but did not report the statistical significance. Eight of these 13 studies reported comparisons to control. Five of the eight studies did not show RBL gain in the laser groups compared to control. In the laser groups compared to baseline, 11 of 13 reported reduced PD, and 6 of 13 reported significantly reduced BOP. Compared to the control, eight of the eight reported reduction of PD, and three of six reported significantly reduced BOP. Statistical significance was not consistently reported. (4) Conclusions: Within the limits of this systematic review, laser treatment may promote bone gain in peri-implantitis defects, may reduce BOP and PDs, and may be comparable to mechanical therapy. However, definitive conclusions can only be made with statistically significant data, which were found lacking in the currently available studies. This systematic review was registered with the National Institute for Health Research, international prospective register of systematic reviews (PROSPERO): CRD42020207972.

Presence of Specific Periodontal Pathogens in Prostate Gland Diagnosed With Chronic Inflammation and Adenocarcinoma.

Background Intraprostatic inflammation is frequently observed in the prostate and linked to prostatic diseases, including prostatitis, benign prostatic hyperplasia (BPH), and cancer. The etiology of prostate diseases is unclear. Periodontal diseases are associated with an increased risk of prostate diseases. In men, chronic prostatitis and moderate/severe periodontitis have significantly elevated serum prostate-specific antigen (PSA) levels. Treatment of periodontal disease reduced PSA levels in men. The presence of periodontal pathogens deoxyribonucleic acid (DNA) was identified in the prostate fluid of prostatitis patients. These pathogenic bacteria might have the potential to trigger prostatitis progressing to prostatic adenocarcinoma. The mechanism(s) explaining the etiology of association between periodontal disease and prostate cancer remains unclear. However, the presence of periodontal pathogens has not been analyzed in the prostate gland. Objective To identify and compare the presence of specific periodontal pathogens in the areas of BPH, inflammation, and cancer of the prostate glands diagnosed with malignancy. Materials and methods Whole-mount radical prostatectomy sections from men (n=30) were identified for BPH, inflammation, and cancer areas and marked for tissue procurement. The tissues were subjected to DNA isolation and analysis of microbial DNA and total bacterial load for the following pathogens, including Porphyromonas gingivalis strain ATCC 33277, Prevotella intermedia strain B422, Treponema denticola strain 35405, Fusobacterium nucleatum subsp. fusiform strain, Tannerella forsythia strain ATCC 43037, and Campylobacter​​​​​​​ rectus strain ATCC 33238performed real-time PCR. The universal bacterial primer pairs were used to detect genomic DNA (gDNA) from the total bacteria present in the samples. All species-specific primers were designed to target the variable regions of the 16S ribosomal RNA (rRNA). Data were analyzed using the 2-ΔΔCT method, statistically validated using unpaired t-test and ANOVA test. Results A total of 90 samples of prostate tissue specimens were analyzed for periodontal pathogens; only one pathogen (F. nucleatum subsp. fusiform strain ATCC 51190) showed a significant difference compared to the expression of S. epidermidis (internal control). In particular, F. nucleatum expression was 9, 11.9, and 10.3-fold higher in BPH, inflammation, and cancer, respectively, at p-value <0.05. Moreover, the bacterial load abundance/expression was almost similar in BPH (46.8-fold), inflammation (40.9 fold), and cancer (41.5 fold) higher. There was no significant difference in bacterial load (folder change) among the three areas of BPH, inflammation, and cancer (p-valve>0.05). Similarly, there was no significant difference between F. nucleatum (folder change) among the three areas (p-valve>0.05). Conclusion  Fusobacterium nucleatum is identified in the prostates that harbor cancer, chronic inflammation, and BPH.

Microbial Profiling in Experimentally Induced Biofilm Overgrowth Among Patients With Various Periodontal States.

BACKGROUND: This study measures microbial composition changes during biofilm overgrowth and subsequent removal among patients with various states of periodontal disease. METHODS: In this prospective cohort study, 175 participants with various periodontal states (five biofilm-gingival interface [BGI] groups) abstained from oral hygiene while using an acrylic stent. At day 21, participants reinstituted oral hygiene and were followed for 4 weeks. Clinical parameters were recorded, and subgingival plaque samples were analyzed at baseline, peak of induction (day 21), and resolution using 16S rRNA probes (human oral microbe identification microarray [HOMIM]). Using the change score (peak at induction minus baseline) for bleeding on probing and probing depth (PD), the patients were separated into high and low clinical responders. RESULTS: At baseline, synergistetes were more abundant in moderate and severe periodontitis (BGI-P2 and -P3) compared to mild periodontitis (BGI-P1), health (BGI-H), and gingivitis (BGI-G) (P = 0.005). Overall, at day 21 there was an increase in HOMIM scores of firmicutes (P ≤0.001), fusobacteria (P = 0.003), proteobacteria (P ≤0.001), synergistetes (P = 0.04), and bacteroidetes (P ≤0.001). At resolution, these phyla returned to baseline, except for synergistetes. Levels of synergistetes were significantly higher at day 21 (P ≤0.0001) and resolution (P = 0.0002) for high clinical responders compared to low responders. CONCLUSION: The association of synergistetes as a baseline predictor of incident PD increase, as well as the higher levels at day 21, indicates a pathogenic role for these organisms in disease progression in addition to the previously characterized fusobacteria, proteobacteria, firmicutes, and bacteroidetes.