A Novel Method to Assess Antimicrobial Susceptibility in Commensal Oropharyngeal Neisseria—A Pilot Study

Commensal Neisseria provide a reservoir of resistance genes that can be transferred to the pathogens Neisseria gonorrhoeae and N. meningitidis in the human oropharynx. Surveillance programs are thus needed to monitor resistance in oropharyngeal commensal Neisseria, but currently the isolation and antimicrobial susceptibility testing of these commensals is laborious, complex and expensive. In addition, the posterior oropharyngeal/tonsillar swab, which is commonly used to sample oropharyngeal Neisseria, is poorly tolerated by many individuals. We evaluated an alternative non-invasive method to isolate oropharyngeal commensal Neisseria and to detect decreased susceptibility to azithromycin using selective media (LBVT.SNR) with and without azithromycin (2 µg/mL). In this pilot study, we compared paired posterior oropharyngeal/tonsillar swabs and oral rinse-and-gargle samples from 10 participants and demonstrated that a similar Neisseria species diversity and number of colonies were isolated from both sample types. Moreover, the proportion of Neisseria colonies that had a decreased susceptibility to azithromycin was similar in the rinse samples compared to the swabs. This pilot study has produced encouraging data that a simple protocol of oral rinse-and-gargle and culture on plates selective for commensal Neisseria with and without a target antimicrobial can be used as a surveillance tool to monitor antimicrobial susceptibility in commensal oropharyngeal Neisseria. Larger studies are required to validate these findings.

A Pilot Study on the Degree of Tooth Staining Caused by Pollen Water and Chlorhexidine: In Vitro Study

Background: Chlorhexidine oral rinse has been used as an adjuvant in the treatment of periodontal disease. However, there are drawbacks of using chlorhexidine i.e. tooth staining and other side effects, including allergy reaction. In light of the proven therapeutic properties of pollen water as well as its relatively cheap cost in the market, pollen water has a potential to be an effective alternative to chlorhexidine oral rinse. The aim of this study is to compare the degree of tooth staining influenced by water-based pollen mouthwash to the standard Chlorhexidine mouthwash using spectrophotometer. Materials and Methods: 24 specimens from extracted intact human teeth were soaked into the three different solutions, Chlorhexidine, Pollen water (date palm pollen water suspension), and normal water. Color measurements were carried out by a spectrophotometer devise and recorded at 5 different time intervals. Color change (∆E), Chroma (C*) and Hue (H*) were analyzed and compared among the three solutions. Results: Overall mean ∆E was similar in all groups, significant difference between all time points was found only in pollen water. The change in C* was higher in pollen water as compared to other solutions. There was a subtle increase in H* in the Chlorhexidine samples after week 3. The H* values in pollen water were stable, but a sudden decrease was observed in week 6. The difference in H* among the three solutions was significant after 3 weeks. Conclusion: Within the limitation of our study, it can be concluded that Pollen water stained teeth to a lesser extent than did chlorhexidine. It might be beneficial to use Pollen water as mouthwash however, further investigation is needed regarding the efficacy of plaque control.

Clinical Audit of Two Standard Surgical Site Treatments Following Dental Extractions and The Impact on Incidence of Alveolar Osteitis Within a Specialist Dental Clinic

Background Alveolar osteitis is a painful condition following dental extraction associated with absence of blood clot and consequent exposure of underlying alveolar bone. It is a condition whose exact aetiology is unresolved and a known complication in up to 30-40% of dental extractions. The following report details a retrospective evaluation of two approved, long-standing wound care treatments used, post-extraction, within our clinic to assess for relationship with alveolar osteitis incidence. Methods Patients undergoing non-acute dental extraction at a dental out-patient clinic in the UK had received two different standard treatments for a period from 2000 to 2014. The treatments were mouth rinse with physiologic saline or surgical site irrigation and mouth rinse with physiologic saline-low dose aqueous chlorine used in wound and burn-site care. Retrospective, post-operative outcome analysis suggested improved outcomes with one of the standard treatments versus the other. A full retrospective audit of consecutive treatment outcomes was implemented to test the hypothesis. The audit data-collection was blinded to the treatment administered and to the identity of the treating clinician. Statistical analysis was carried out independently and blinded to the treatment modality. Results All patients were routinely reviewed within seven days and a determination of un-complicated healing vs alveolar osteitis (requiring further intervention) was made. Our results show that treatment with of aqueous chlorine in physiological saline significantly reduced the incidence of alveolar osteitis versus the control group who received physiologic saline without socket irrigation and chlorhexidine oral rinse home-care. (Odds Ratio 0.0146 Relative Risk 0.029 (95%CI 0.0093 to 0.0928) significance (p<0.001). Conclusions This is the first report to show an extremely significant reduction in the incidence of alveolar osteitis following treatment with low dose aqueous chlorine in physiological saline compared with those receiving the physiologic saline and saline mouth rinse or Corsodyl mouth rinse. This shows an approach to surgical site care is superior to the most common, reported, standard of care treatment. The impact of this has led to improved antibiotic stewardship within the clinic for dental extraction or elective oral surgery, including third molars.

Essential oils utility implications in symptomatic Burning Mouth Syndrome

Introduction. Burning mouth syndrome (BMS) is a clinical condition characterized by the presence of chronic pain in absence of clinically visible lesions of the oral mucosa. The etiology is uncertain and the therapeutic strategies still controversial. The objective of this prospective study is to analyze the efficacy of essential oils-based mouthwashes in the therapy of BMS. Material and method. This study included 16 patients affected by BMS who were treated with essential oils-based mouthwashes and glucose solution on alternated days for 30 days. Symptomatology was evaluated after 15, 30 and 90 days. Results and discussions. A the end of the treatment, most of the patients (67%) referred an improvement of symptoms up to complete remission in 90 days. Conclusions. Based on this study, essential oils-based mouthwashes could represent a valid aid in the treatment of BMS. Further studies are necessary in order to identify effective and standardized therapeutic protocols. Keywords: Burning Mouth Syndrome; oral rinse; essential oils; therapeutic strategies,

Decreased Levels of Soluble CD44 in a High-Risk Population following a Smoking Cessation Program

Tobacco is a risk factor of head and neck cancer (HNC) and smoking cessation alone may reduce HNC risk by 70%. Soluble CD44 (solCD44), a cell surface receptor linked to cell proliferation and migration, and total protein (TP) levels can detect early HNC. This study aims to determine whether salivary solCD44 and TP levels in oral rinses change following a smoking cessation program. 150 smokers provided oral rinse samples at baseline and at a 12-month follow-up after participation in a smoking cessation program. Assays to measure levels of solCD44, TP, and cotinine, a metabolite used as a biomarker of tobacco exposure, were completed. A paired-samples t-test was used to determine whether there was a statistically significant (p < 0.05) mean difference in biomarker levels before and after the program. Baseline and at 12-month follow-up data were available for 88 subjects, 21 of whom quit smoking entirely. Mean levels of solCD44 significantly decreased by 0.412 ng/mL from baseline to the 12-month follow-up, p = 0.010. There was no significant difference in mean TP levels, p = 0.975. Mean cotinine levels decreased significantly by 74.7 ng/mL, p = 0.035. This is the first work demonstrating an association between smoking cessation and decreased solCD44 levels in oral rinses. Decreased expression of the tumorigenic CD44 may be one mechanism by which smoking cessation lowers cancer risk.

Effects of Removal Conditions on Mercury Amount Remaining in the Oral Cavity and inside Drainage System after Removing Dental Amalgams

Mercury is produced and drained into the environment by removing dental amalgams, which may cause mercury pollution. This study aimed to clarify the mercury amount remaining in the oral cavity and inside the drain system after removal. The effects of the removal conditions and differences in drainage systems were also investigated. Dental amalgams filled in the tooth and placed in a phantom head were removed using an air turbine under several conditions (two removal methods, absence of cooling water, and intraoral suction). Then, the oral cavity was rinsed with 100 mL of water (oral rinse water), and 500 mL of water was suctioned to wash the inside of the drainage system (system rinse water). Both water samples were collected in two ways (amalgam separator and gas-liquid separator), and their mercury amounts were measured. It was found that the amount of mercury left in the oral cavity and drainage system after dental amalgams removal could be reduced when the amalgams were removed by being cut into fragments as well as using cooling water and intraoral suction. In addition, using amalgam separators can significantly reduce the amount of mercury in the discharge water and prevent the draining of mercury into the environment.

Chlorhexidine oral rinses for symptomatic COPD: a randomised, blind, placebo-controlled preliminary study

ObjectivesDetermine the effect of twice-daily chlorhexidine oral rinses on oral and lung microbiota biomass and respiratory symptoms.SettingSingle centre.ParticipantsParticipants were aged 40–85 with chronic obstructive pulmonary disease (COPD) and chronic productive cough or COPD exacerbation within the last year. Exclusions included antibiotics in the previous 2 months and/or those with less than four teeth. Forty-four participants were recruited and 40 completed the study.InterventionParticipants were randomised 1:1 to twice-daily 0.12% chlorhexidine oral rinses versus placebo for 2 months along with daily diaries. St. George’s Respiratory Questionnaire (SGRQ), blood tests, oral rinse and induced sputum were collected at randomisation and the final visit.Primary and secondary outcomesPrimary outcome was a change in oral and sputum microbiota biomass. Secondary outcomes included: sputum and oral microbiota Shannon and Simpson diversity and taxonomy; inflammatory markers; Breathlessness, Cough and Sputum Scale and SGRQ scores.ResultsNeither the oral microbiota nor the sputum microbiota biomass decreased significantly in those using chlorhexidine compared with placebo (oral microbiota mean log10 difference (SE)=−0.103 (0.23), 95% CI −0.59 to 0.38, p=0.665; sputum microbiota 0.80 (0.46), 95% CI −0.15 to 1.75, p=0.096). Chlorhexidine decreased both oral and sputum microbiota alpha (Shannon) diversity (linear regression estimate (SE) oral: −0.349 (0.091), p=0.001; sputum −0.622 (0.169), p=0.001). Chlorhexidine use did not decrease systemic inflammatory markers compared with placebo (C reactive protein (chlorhexidine 1.8±7.5 vs placebo 0.4±6.8, p=0.467), fibrinogen (22.5±77.8 vs 10.0±77.0, p=0.406) or leucocytes (0.2±1.8 vs 0.5±1.8, p=0.560)). Chlorhexidine use decreased SGRQ scores compared with placebo (chlorhexidine −4.7±8.0 vs placebo 1.7±8.9, p=0.032).ConclusionsWe did not detect a significant difference in microbiota biomass due to chlorhexidine use. Chlorhexidine decreased oral and sputum microbiota alpha diversity and improved respiratory health-related quality of life compared with placebo.Trial registrationNCT02252588.

Exploring the roles of HPV16 variants in head and neck squamous cell carcinoma: current challenges and opportunities

The incidence of squamous cell carcinomas of the head and neck (HNSCC) is consistently increasing, in association with human papillomavirus (HPV) infection, especially HPV16. HPV variants show heterogeneity in the pathogenicity of cervical cancer, but little has been established about their relevance on HNSCC. This review addresses the distribution of HPV16 variants in HNSCC and their potential contribution to clinical practice. A search was performed in PubMed using the keywords HNSCC HPV16 variants. Sixty articles were identified between 2000 and 2020 and 9 articles were selected for a systematic analysis. Clinical cohorts comprised 4 to 253 patients aged between 17 and 91 years with confirmed HPV16-positive HNSCC. Samples were collected from fresh biopsies of the tumour, oral rinse or formol fixed/paraffin embedded tissue, from the oral cavity, oropharynx, hypopharynx, larynx and Waldeyer's tonsillar ring. HPV16 variants were identified using Sanger sequencing techniques. Seven studies addressed the HPV16 E6 gene, one studied E6 and E7, another studied L1 and one focused on the long control region. European variants represent 25–95%, Asian-American 5–57% and African 2–4% of the total isolates, suggesting a marked predominance of European strains. No correlations could be drawn with patient prognosis, partly because many studies relied on small patient cohorts. Additional studies are needed, particularly those employing next generation sequencing techniques (NGS), which will allow faster and accurate analysis of large numbers of samples.

Restoration of the Oral Microbiota After Surgery for Head and Neck Squamous Cell Carcinoma Is Associated With Patient Outcomes

ObjectiveTo evaluate the dynamics of the oral microbiome and associated patient outcomes following treatment of head and neck squamous cell carcinoma (HNSCC).Materials and MethodsThis was a prospective cohort study at a tertiary academic center in Hong Kong SAR of patients with head and neck squamous cell carcinoma evaluating the oral microbiome in pre- and postsurgery oral rinses (at 1, 3, and 6 months) with 16S rRNA gene V3–V4 amplicon sequencing.ResultsIn total, 76 HNSCC patients were evaluated. There was a significantly depressed alpha diversities of oral microbial communities observed in HNSCC oral rinse samples within the first 6 months post-surgery when compared to presurgery or healthy controls. Distant clustering between pre- and postsurgery was also observed (p &lt; 0.022). Following treatment, eight oral bacterial genera showed a trend towards the restoration in the relative abundances that approximate healthy persons. In evaluating patient outcomes, the decreased relative abundance of three periodontal bacteria (Capnocytophaga, Prevotella 7, and Leptotrichia) and the increased relative abundance of two commensal bacteria (Streptococcus and Rothia) at 6 months postsurgery compared to presurgery showed a better 3-year disease-specific survival (a cutoff of Kaplan–Meier survival curve test p &lt; 0.3 at 36 months). In particular, the postsurgery restoration of Prevotella 7 was statistically significant in the surveyed patients (survival rate of 84% vs. 56% at 36 months, p = 0.0065).ConclusionsOral microbiome dysbiosis associated with HNSCC is dynamic. These dynamics of the oral microbiome postsurgery are also associated with patient treatment and outcomes and may serve as potential biomarkers for patient management in HNSCC.