[Phytosphingosine, a new ingredient for oral care products?]

Despite the availability of a wide range of (fluoridated) oral care products, there is a constant search under way for new substances that contribute to a healthy mouth. Laboratory research shows that the lipid phytosphingosine forms a molecular layer on hydroxyapatite and protects it against acid-induced demineralization and bacterial adhesion. In the future, phytosphingosine may be used in the future as a new ingredient in oral care products for the prevention of tooth erosion and biofilm-related disorders, such as caries, gingivitis and periodontitis.

Yunnan Baiyao Inhibits Periodontitis by Suppressing the Autophagic Flux

BACKGROUND

Yunnan Baiyao (YNBY), a traditional Chinese medicine, is renowned for its anti-inflammatory properties. Recent studies have suggested that YNBY plays a significant role in inhibiting osteoclast differentiation and autophagy, which are essential processes in inflammation and bone resorption associated with periodontitis. However, the precise relationship between autophagy and the mechanism by which YNBY inhibits osteoclastogenesis remains unexplored.The primary objective of this study was to investigate the inhibitory effects of YNBY on the process of osteoclastogenesis and its potential in preventing inflammatory bone loss.

METHODS

The animals were subjected to sacrifice at intervals of 2, 4, and 6 weeks postintervention whilst under deep anaesthesia, and specimens were subsequently collected. The specimens were subjected to hematoxylin and eosin (HE) staining, in addition to tartrate-resistant acid phosphatase (TRAP) staining and subsequently imaged employing a digital scanner. The confirmation of osteoclast (OC) differentiation and autophagic flux was achieved through various techniques, including western blotting, transmission electron microscopy (TEM), TRAP staining, pit formation assay, and immunofluorescence.

RESULTS

The microcomputed tomography images provided evidence of the effective inhibition of alveolar bone absorption at 2, 4, and 6 weeks following YNBY treatment. Additionally, the histomorphometric evaluations of tissue segments stained with HE and TRAP, which involved measuring the distance between the alveolar bone crest (ABC) and cementoenamel junction (CEJ) and quantifying TRAP-positive OCs, yielded comparable results to those obtained through computed tomography analysis. YNBY treatment resulted in a decrease in the CEJ-ABC distance and inhibition of OC differentiation. Furthermore, in vitro studies showed that the autophagy modulators rapamycin (RAP) and 3-methyladenine (3-MA) significantly affected OC differentiation and function. YNBY attenuated the impact of RAP on the differentiation of OCs, autophagy-related factor activation, and bone resorption.

CONCLUSIONS

We hypothesise that YNBY suppresses the differentiation of OC and bone resorption by blocking autophagy. This study reveals that targeting autophagy might be a new alternative treatment methodology for periodontitis treatment.

Interdental cleaning aids are beneficial for oral health at 7-year follow-up: Results from the Study of Health in Pomerania (SHIP-TREND)

AIM

To estimate association between the use of interdental cleaning aids (IDAs) and type on 7-year follow-up levels of interdental plaque, interdental gingival inflammation, interdental periodontitis severity, the number of interdental sound surfaces and the number of missing teeth in a population-based cohort study.

MATERIALS AND METHODS

We used 7-year follow-up data of 2224 participants from the Study of Health in Pomerania (SHIP-TREND). We applied generalized linear and ordinal logistic models, adjusting for confounding and selection bias using inverse probability treatment weighting and multiple imputation.

RESULTS

Flossers were 32% less likely to have higher interdental plaque (iPlaque) levels than non-users of IDAs (odds ratio [OR] = 0.68; 95% confidence interval [CI]: 0.50-0.94); flossing resulted in 5% lower means of iPlaque. Effects on interdental bleeding on probing (iBOP), mean interdental probing depths and mean interdental clinical attachment levels were direction-consistent but statistically non-significant. Interdental brushing was associated with lower follow-up levels for interdental plaque (OR = 0.73; 95% CI: 0.57-0.93) and iBOP (OR = 0.69; 95% CI: 0.53-0.89). IDAs were more effective in reducing iPlaque in participants with periodontitis, whereas iBOP reduction was more pronounced in participants with no or mild periodontitis. The analyses did not suggest that the use of IDAs affected caries. Finally, applying change score analyses, flossing reduced tooth loss incidence (incidence rate ratio [IRR] = 0.71) compared with non-users of IDAs.

CONCLUSIONS

Recommending flossing and interdental brushing in dental practices represents an approach to the prevention of gingivitis and consequently periodontitis.

The relationship of dietary flavonoids and periodontitis in US population: a cross-sectional NHANES analysis

OBJECTIVES

We investigated the association between dietary flavonoids intake and periodontitis.

MATERIALS AND METHODS

This cross-sectional study analyzed data from the US National Health and Nutrition Examination Survey 2009-2010 on 3025 participants aged between 30 and 80 years who had full-mouth periodontal examination and dietary flavonoids intake data. This study used periodontal pocket depth (PPD) and clinical attachment loss (CAL) as periodontitis markers. Data were analyzed using multivariate linear regression.

RESULTS

After adjusting confounders, the middle tertile of total dietary flavonoids was associated with decreased mean PPD (0.06 mm, P = 0.016) and mean CAL (0.13 mm, P = 0.001) and the top tertile of total dietary flavonoids was significantly associated with decreases in mean PPD (0.05 mm, P = 0.029) and mean CAL (0.11 mm, P = 0.010). Both the middle and top tertiles of total flavonoids intake were significantly related with decreased mean CAL in females, those flossing 0 days/week, overweight and non-diabetic population but not in males, smokers, those flossing 1-6 days/week and diabetic population. Higher anthocyanidins, flavones and flavonols intake was significantly associated with decreased mean PPD and mean CAL while higher flavanones intake was only significantly associated with decreased mean CAL. Higher anthocyanidins intake was particularly related with greatest decreases in mean CAL (top tertile: 0.22 mm, middle tertile: 0.17 mm, both P < 0.010). However, no significant associations were found between isoflavones and flavan_3_ols intake and mean CAL.

CONCLUSIONS

Higher dietary flavonoids intake may be beneficial for periodontal health.

CLINICAL RELEVANCE

Additional anthocyanidins, flavanones, flavones and flavonols intake was associated with improved periodontal health.

Preventive effects of systemic Pistacia eurycarpa Yalt. administration on alveolar bone loss and oxidative stress in rats with experimental periodontitis

OBJECTIVE

This study aimed to investigate the effects of systemic administration of P. eurycarpa Yalt. plant extract on alveolar bone loss and oxidative stress biomarkers in gingival tissue in a rat model of experimental periodontitis.

METHODOLOGY

32 male Wistar albino rats, weighing 200-250 g, were divided into four groups (n=8): Healthy control (HC), Experimental periodontitis control (EPC), Experimental periodontitis 400 mg/kg (EP400), Experimental periodontitis 800 mg/kg (EP800). Experimental periodontitis was induced using the ligating method. Distilled water was administered to the HC and EPC groups and the plant extract was administered to the EP400 and EP800 groups by oral gavage at doses of 400 mg/kg and 800 mg/kg, respectively. The rats were sacrificed on the 15th day. The values of glutathione peroxidase GSH-Px, malondialdehyde (MDA), superoxide dismustase (SOD), interleukin-1β (IL-1β), interleukin-10 (IL-10), total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI) in the gingival tissues were analyzed by ELISA tests. Alveolar bone loss was assessed using micro-CT images of the maxilla.

RESULTS

Although the IL-1β, TOS, OSI results of the healthy control group were lower than those of the other groups, the TAS values were higher (p<0.05). No significant difference was found in the biochemical parameters among the EPC, EP400, and EP800 groups (p>0.05). Alveolar bone loss was significantly reduced in the extract groups compared to the EPC group (p<0.001).

CONCLUSION

Within the limitations of this study, it was observed that the systemic P. eurycarpa extract application reduced alveolar bone loss in a rat model of experimental periodontitis. Further studies are needed to elucidate the beneficial effects of P. eurycarpa.

rgpA-Engineered/Functionalized DNA Vaccine as a Novel Prophylactic Vaccination to Prevent Porphyromonas gingivalis-Induced Periodontitis: An in Vivo Study

BACKGROUND

Arg-gingipain A (rgpA) and Arg-gingipain B (rgpB) are crucial virulence factors associated with Porphyromonas gingivalis (P. gingivalis) and have been recognized as promising targets for antibacterial vaccines. Although vaccines containing rgpA have shown efficacy, the incorporation of rgpB, which lacks the haemagglutinin adhesin (HA) domain, diminishes the vaccine's effectiveness. This study aims to assess the immunogenicity of the functional HA domain of rgpA in mouse periodontitis models.

METHODS

A total of 24 mice were randomly divided into four groups, each receiving different immune injections: group A received phosphate-buffered saline (PBS) as an empty control; group B received pVAX1 as a negative control (NC); group C received pVAX1-HA; and group D received pVAX1-rgpA. The mice were subjected to intramuscular injections every two weeks for a total of three administrations. Prior to each immunization, blood samples were collected for antibody detection under isoflurane anesthesia. Following the final immunization, periodontitis was induced two weeks later by using sutures soaked in a P. gingivalis solution. The mice were euthanized after an additional two-week period. To assess the safety of the procedure, major organs were examined through hematoxylin-eosin (HE) staining. Subsequently, the levels of IgG, IgG1, and IgG2a in the serum were quantified via enzyme-linked immunosorbent assay (ELISA). Additionally, the expression of inflammatory factors in the gingiva, including interleukin-6 (IL-6), interleukin-1β (IL-1β), and tumor necrosis factor alpha (TNF-α), was determined using quantitative real-time reverse transcript PCR (qRT-PCR). The extent of bone loss in periodontal tissues was evaluated using micro-computed tomography (micro-CT) and HE staining.

RESULTS

HE staining of the organs confirmed the absence of vaccine-induced toxicity in vivo. After the second immunization, both the rgpA and HA groups displayed significantly higher specific IgG titers in comparison to the NC and PBS groups (p < 0.05). Furthermore, the rgpA and HA groups exhibited a noteworthy predominance of IgG1 antibodies after three immunization doses, while there was a noticeable reduction in IgG2a levels observed following ligation with P. gingivalis sutures, as opposed to the NC and PBS groups (p < 0.05). Additionally, both the HA and rgpA groups showed a significant decrease in the expression of inflammatory factors such as IL-6, IL-1β, and TNF-α, as well as a reduction in bone loss around periodontitis-affected teeth, when compared to the NC and PBS groups (p < 0.05).

CONCLUSIONS

The results of this study demonstrate that the rgpA-engineered/functionalized HA gene vaccine is capable of eliciting a potent prophylactic immune response against P. gingivalis-induced periodontitis, effectively serving as an immunogenic and protective agent in vivo.

Association between Mediterranean diet and periodontitis among US adults: The mediating roles of obesity indicators

OBJECTIVE

This study aimed to assess the association between the Mediterranean diet (MedDiet) and periodontitis in US adults and to further explore the mediating roles of obesity indicators in this association.

BACKGROUND DATA

The relationship between MedDiet and periodontitis is controversial. And it is unclear whether obesity indicators are potential mediators of this relationship.

METHODS

Using data derived from the National Health and Nutrition Examination Survey (2009-2014). Weighted binary logistic regression and restricted cubic spline were used to assess the association between MedDiet and periodontitis. Weighted ordinal logistic regression was performed to evaluate the relationship between MedDiet and periodontitis severity. The mediating roles of body mass index (BMI) and waist circumference in the relationship between the MedDiet and periodontitis were explored. Association analyses were further performed using mean clinical attachment loss (CAL) or mean periodontal probing depth (PPD) as dependent variables. The false discovery rate method was used to correct the p-values in the regression analyses.

RESULTS

A total of 8290 eligible participants (4159 participants with periodontitis and 4131 without periodontitis) were included. A negative association between the MedDiet adherence score and periodontitis was observed in the binary logistic regression model (adjusted odds ratio = 0.94, 95% confidence interval: 0.90-0.97, p = .001). Restricted cubic spline regression revealed a dose-response relationship between the MedDiet adherence score and periodontitis. BMI and waist circumference significantly mediate this association, with mediation proportions of 9.7% (p = .032) and 9.3% (p = .012), respectively. Multivariable ordinal logistic regression showed that the MedDiet adherence score was negatively associated with the severity of periodontitis (all p < .05). Additionally, the MedDiet adherence score was negatively associated with mean PPD or mean CAL (all p < .05).

CONCLUSIONS

This study suggests a significant negative association between adherence to the MedDiet and periodontitis and a possible mediating role of obesity indicators in this association. Furthermore, studies are still warranted to confirm our findings.

Motivational interviewing for preventing oral morbidities in adults: Systematic review and meta-analysis

OBJECTIVE

This systematic review with meta-analysis was performed to assess whether motivational interviewing (MI) effectively prevents oral morbidities in adults.

METHODS

Studies considered were randomized controlled trials, cluster-randomized controlled trials and community-based randomized trials assessing interventions based on MI or indicating that a counselling technique based on the principles developed by Miller and Rollnick was used. Controls were any type of oral health education or negative controls. Participants were 18-60 years old. The main outcome was any oral morbidity. From 602 studies identified in MEDLINE, Scopus, Web of Science and LILACS databases, seven studies were included in the synthesis.

RESULTS

Studies included only evaluated periodontal outcomes, no studies were found for other oral morbidities. Patients' mean age was 43.7 years, and the follow-up time after MI or MI-based intervention varied between 1 month and 1 year. The total study population was 272 people with moderate-to-severe periodontitis; other groups analysed were pregnant women (n = 112) and patients with mental disorders and alcohol problems (n = 60). Meta-analysis for the plaque index (four studies, n = 267), bleeding on probing (two studies, n = 177) and gingival index (two studies, n = 166) were carried out. The summary effects for the random-effects model were estimated respectively as -3.59 percentage points (CI: [-11.44; 4.25] for plaque index, -6.41 percentage points (CI: [-12.18, -0.65]) for bleeding on probing and -0.70 (CI: [-1.87; 0.48]) for gingival index, marginally favouring the MI group. The reduced number of studies, the non-disclosure of some aspects of the data and the heterogeneity among them undermine the precision of the estimates.

CONCLUSION

The current evidence available is limited to periodontal outcomes, and it is not possible to determine whether MI effectively prevents oral morbidities in adults.

A diet rich in omega-3 fatty acid improves periodontitis and tissue destruction by MMP2- and MMP9-linked inflammation in a murine model

Periodontitis is an oral-cavity inflammatory disease and is the principal cause associated with tooth loss. Matrix metalloproteinases 2 and 9 (MMP-2 and MMP-9) are important proteases involved in periodontal tissue destruction. The omega-3 polyunsaturated fatty acids (ω-3 PUFA) have been demonstrated to possess immunoregulatory properties in periodontitis. The aim of the study was to investigate the effects of ω-3 PUFA on inflammation and on the expression of MMP-2 and -9 in a murine periodontitis model. Twenty-four male C57BL/6 mice were divided into control mice (Control), control mice treated with ω-3 PUFA (O3), mice with periodontitis (P), and mice with periodontitis treated with ω-3 PUFA (P + O3). ω-3 PUFA were administered orally once a day for 70 days. Periodontitis in mice was induced by Porphyromonas gingivalis-infected ligature placement around the second maxillary molar. The mice were sacrificed, and blood and maxillary samples were collected. Flow cytometry was used to quantify tumor necrosis factor-alpha (TNFα), interleukin (IL)-2, IL-4, IL-5, and interferon-gamma. Histologic analysis and immunohistochemistry for MMP-2 and -9 were performed. The data were statistically evaluated using analysis of variance (ANOVA) and the Tukey post hoc test. Histological analysis showed that ω-3 PUFA supplementation prevented inflammation and tissue destruction and revealed that bone destruction was more extensive in the P group than in the P + O3 group (p < 0.05). Also, it decreased the serum expressions of TNFα and IL-2 and the tissue expression of MMP-2 and -9 in the periodontitis-induced model (p < 0.05). ω-3 PUFA supplementation prevented alveolar bone loss and periodontal destruction, probably by decreasing the expression of MMP-2 and MMP-9 and its immunoregulatory properties.

Adherence to dental home care in dogs with periodontitis: a post-treatment survey

BACKGROUND

Periodontitis is a common disease in dogs, and daily dental home care in the form of tooth brushing is essential for prevention and treatment. Despite this, many studies reveal low adherence to tooth brushing advice. This study aimed to assess compliance with dental home care among dogs with periodontitis and understand the factors influencing brushing routines. A questionnaire survey was emailed to 63 dog owners whose dogs had been diagnosed with periodontitis, received dental cleaning at the University Animal Hospital, Swedish University of Agricultural Sciences and were given tooth brushing instructions. The survey was supplemented by telephone interviews, resulting in a 57% response rate.

RESULTS

The study presents dog owners' routines, experiences, attitudes, and motivation regarding tooth brushing. Approximately 42% brushed their dogs' teeth daily while others did so less frequently or not at all. Reported challenges, such as uncooperative dogs and difficulty establishing a routine, may explain infrequent brushing.

CONCLUSIONS

While the study suggests that owners of dogs with periodontitis tend to follow dental care recommendations better than the general dog owner population, it also reveals that preventive care is inadequate for more than half of the dogs. Given the high prevalence of periodontitis, there's a need for resources to address infrequent tooth brushing. Understanding dog owners' needs can help establish daily brushing as a routine, improving canine oral health and overall well-being.

CCL2 is a key regulator and therapeutic target for periodontitis

AIM

Our previous study revealed that the C-C motif chemokine receptor 2 (CCR2) is a promising target for periodontitis prevention and treatment. However, CCR2 is a receptor with multiple C-C motif chemokine ligands (CCLs), including CCL2, CCL7, CCL8, CCL13 and CCL16, and which of these ligands plays a key role in periodontitis remains unclear. The aim of the present study was to explore the key functional ligand of CCR2 in periodontitis and to evaluate the potential of the functional ligand as a therapeutic target for periodontitis.

MATERIALS AND METHODS

The expression levels and clinical relevance of CCR2, CCL2, CCL7, CCL8, CCL13 and CCL16 were studied using human samples. The role of CCL2 in periodontitis was evaluated by using CCL2 knockout mice and overexpressing CCL2 in the periodontium. The effect of local administration of bindarit in periodontitis was evaluated by preventive and therapeutic medication in a mouse periodontitis model. Microcomputed tomography, haematoxylin and eosin staining, tartrate-resistant acid phosphatase staining, real-time quantitative polymerase chain reaction, enzyme-linked immunosorbent assay, bead-based immunoassays and flow cytometry were used for histomorphology, molecular biology and cytology analysis.

RESULTS

Among different ligands of CCR2, only CCL2 was significantly up-regulated in periodontitis gingival tissues and was positively correlated with the severity of periodontitis. Mice lacking CCL2 showed milder inflammation and less bone resorption than wild-type mice, which was accompanied by a reduction in monocyte/macrophage recruitment. Adeno-associated virus-2 vectors overexpressing CCL2 in Ccl2-/- mice gingiva reversed the attenuation of periodontitis in a CCR2-dependent manner. In ligation-induced experimental periodontitis, preventive or therapeutic administration of bindarit, a CCL2 synthesis inhibitor, significantly inhibited the production of CCL2, decreased the osteoclast number and bone loss and reduced the expression levels of proinflammatory cytokines TNF-α, IL-6 and IL-1β.

CONCLUSIONS

CCL2 is a pivotal chemokine that binds to CCR2 during the progression of periodontitis, and targeting CCL2 may be a feasible option for controlling periodontitis.

Selective BET inhibitor RVX-208 ameliorates periodontal inflammation and bone loss

AIM

To determine the effects of RVX-208, a selective bromodomain and extra-terminal domain (BET) inhibitor targeting bromodomain 2 (BD2), on periodontal inflammation and bone loss.

MATERIALS AND METHODS

Macrophage-like cells (RAW264.7) and human gingival epithelial cells were challenged by Porphyromonas gingivalis (Pg) with or without RVX-208. Inflammatory gene expression and cytokine production were measured by reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. RAW264.7 cells were induced to osteoclast differentiation. After RVX-208 treatment, osteoclast differentiation was evaluated by histology, tartrate-resistant-acid-phosphatase (TRAP) activity and the expression of osteoclast-specific genes. The effect of RVX-208 on osteoclast transcriptome was studied by RNA sequencing. Periodontitis was induced in rats by ligature and local RVX-208 treatment was administered every other day. Alveolar bone loss was measured by micro-computed tomography.

RESULTS

RVX-208 inhibited inflammatory gene expression and cytokine production in Pg-infected cells. Osteoclast differentiation was inhibited by RVX-208, as evidenced by reduced osteoclast number, TRAP activity and osteoclast-specific gene expression. RVX-208 displayed a more selective and less profound suppressive impact on transcriptome compared with pan-BET inhibitor, JQ1. RVX-208 administration prevented the alveolar bone loss in vivo.

CONCLUSIONS

RVX-208 regulated both upstream (inflammatory cytokine production) and downstream (osteoclast differentiation) events that lead to periodontal tissue destruction, suggesting that it may be a promising 'epi-drug' for the prevention of periodontitis.

Association of oral care with periodontitis and glycemic control among US adults with diabetes

BACKGROUND

Studies indicate that treating periodontitis may benefit glycemic control among people with diabetes. It is unclear whether oral self-care such as flossing may reduce risk for periodontitis and improve glycemic control among people with diabetes. The purpose of this study was to examine associations between oral care, specifically, flossing and preventive dental care, with periodontitis and glycemic control, among US dentate adults with diabetes.

METHODS

We analyzed data from the National Health and Nutrition Examination Survey 2011-2014 for 892 participants aged 30 years and older with diabetes who completed the periodontal examination and lab test for hemoglobin A1c (HbA1c). Sampling weights were applied. Multivariable logistic regression and multivariable linear modeling were performed to examine the associations of flossing and preventive dental services on periodontal health and HbA1c levels, respectively, controlling for sociodemographic characteristics, health behaviors, and other risk factors.

RESULTS

Among U.S. dentate adults with diabetes, 52.1% of flossers and 72.1% of non-flossers had periodontitis (p < 0.001). Flossers were 39% less likely to have periodontitis (Adj. OR 0.61, 95% CI 0.43-0.88) compared to non-flossers. Flossers had an average HbA1c reading 0.30% (95% CI 0.02%-0.58%) lower than non-flossers, adjusted for covariates (p = 0.037). Preventive dental visits were associated with reduced risk for periodontitis (Adj. OR 0.54, 95%CI, 0.38-0.75) but not glycemic control.

CONCLUSION

Flossing was associated with periodontal health and glycemic control among US adults with diabetes. Although further research is needed, the findings support that oral self-care may be particularly beneficial for adults with diabetes.

Multi-function screening of probiotics to improve oral health and evaluating their efficacy in a rat periodontitis model

The oral cavity is the second most microbially rich region of the human body, and many studies have shown that there is a strong association between microorganisms and oral health. Some pathogenic bacteria produce biofilms and harmful metabolites in the mouth that may cause oral problems such as oral malodor, periodontitis, and dental caries. Altering the oral microbiota by using probiotics may alleviate oral health problems. Thus, using multi-function screening, we aimed to identify probiotics that can significantly improve oral health. The main parameters were the inhibition of pathogenic bacteria growth, inhibition of biofilm formation, reduction in the production of indole, H2S, and NH3 metabolites that cause halitosis, increase in the production of H2O2 to combat harmful bacteria, and co-aggregation with pathogens to prevent their adhesion and colonization in the oral cavity. Tolerance to cholic acid and choline was also assessed. Bifidobacterium animalis ZK-77, Lactobacillus salivarius ZK-88, and Streptococcus salivarius ZK-102 had antibacterial activity and inhibited biofilm production to prevent caries. They also improved the oral malodor parameter, H2S, NH3, and indole production. The selected probiotics (especially L. salivarius ZK-88) alleviated the inflammation in the oral cavity of rats with periodontitis. The analysis of the gingival crevicular fluid microbiome after probiotic intervention showed that B. animalis ZK-77 likely helped to restore the oral microbiota and maintain the oral microecology. Next, we determined the best prebiotics for each candidate probiotic in order to obtain a formulation with improved effects. We then verified that a probiotics/prebiotic combination (B. animalis ZK-77, L. salivarius ZK-88, and fructooligosaccharides) significantly improved halitosis and teeth color in cats. Using whole-genome sequencing and acute toxicity mouse experiments involving the two probiotics, we found that neither probiotic had virulence genes and they had no significant effects on the growth or development of mice, indicating their safety. Taking the results together, B. animalis ZK-77 and L. salivarius ZK-88 can improve oral health, as verified by in vivo and in vitro experiments. This study provides a reference for clinical research and also provides new evidence for the oral health benefits of probiotics.

Association between probiotic consumption and periodontitis: Evidence from NHANES 2009-2014

AIM

The study aimed to provide evidence of the relationship between probiotics consumption and periodontitis.

MATERIALS AND METHODS

A total of 4577 adults who participated in the National Health and Nutrition Examination Survey (NHANES) during 2009-2014 were included in the study. The weighted prevalence of periodontitis was compared among different groups, and a weighted binary logistic regression analysis was conducted to explore the relationship between probiotic consumption and periodontitis. Receiver operating characteristic (ROC) curves were used to assess the role of probiotic consumption in the periodontitis prediction model.

RESULTS

Participants who consumed probiotics had a significantly lower prevalence of periodontitis than those who did not (41.08% vs. 27.83%, p < .001). After fully adjusting for all factors, the odds ratio associated with periodontitis for consuming probiotics was 0.70 (95% confidence interval 0.54-0.92, p = .01) when compared with those who did not consume probiotics. A predictive model including age, sex, ethnicity, poverty income ratio, smoking status and probiotics had 77.0% sensitivity and 60.3% specificity in detecting periodontitis in US adults and achieved an area under the ROC curve of 0.749.

CONCLUSIONS

These results indicate that consuming probiotics is associated with a reduced risk of periodontitis.

Healthier Smile: The Role of Diet and Nutrition in the Prevention and Therapy of Caries, Gingivitis, and Periodontitis

Although oral hygiene and fluorides have a significant impact on people's oral health, we must not forget that the causes of oral diseases are often related to malnutrition and other unhealthy behavioral factors, such as smoking, being sedentary, and chronic stress [...].

[Application of metronidazole combined with minocycline in reducing infection after dental implant in patients with localized periodontitis]

PURPOSE

To explore the value of metronidazole combined with minocycline in reducing infection after dental implant in patients with localized periodontitis.

METHODS

A total of 120 patients with localized periodontitis who underwent dental implantation in the Department of Stomatological, Shanghai Pudong New Area People's Hospital from August 2021 to September 2022 were selected. According to the way of postoperative infection prevention, the patients were divided into control group and experimental group, with 60 patients in each group. The control group was orally given roxithromycin capsules, and the experimental group was locally coated with minocycline hydrochloride ointment and metronidazole gel. The incidence of postoperative infection and complications was compared between the two groups. The modified gingival creval bleeding index (mSBI), periodontal probing depth (PD) and modified plaque index (mPLI) of the patients were examined by periodontal probe. Serum C-reactive protein (CRP) level was determined by immunoturbidimetry and tumor necrosis factor-α(TNF-α) and interleukin-6(IL-6) level was determined by ELISA. SPSS 25.0 software package was used for statistical analysis of the data.

RESULTS

Good healing rate of the experimental group was 91.67% higher than that of the control group 73.33%, postoperative infection rate was 8.33% and complication rate was 6.67% in the experimental group, significantly lower than that of the control group (26.67% and 20.00%), respectively (P＜0.05). After treatment, the level of CRP, TNF-α and IL-6 in the experimental group were significantly lower than those in the control group (P＜0.05). At 3 and 6 months after treatment, mSBI, mPLI and PD in the experimental group were significantly lower than those in the control group(P＜0.05).

CONCLUSIONS

The administration of minocycline hydrochloride and metronidazole in patients with localized periodontitis undergoing implantation can reduce oral inflammatory response, reduce postoperative infection and other complications, and improve periodontal health.

Bifidobacterium animalis subspecies lactis HN019 can reduce the sequelae of experimental periodontitis in rats modulating intestinal parameters, expression of lipogenic genes, and levels of hepatic steatosis

OBJECTIVE

To determine whether Bifidobacterium animalis subspecies lactis HN019 (B. lactis HN019) can reduce the sequelae of experimental periodontitis (EP) in rats modulating systemic parameters.

BACKGROUND

This study evaluated the effects of probiotic therapy (PROB) in the prevention of local and systemic damage resulting from EP.

METHODS

Forty-eight rats were allocated into four groups: C (control), PROB, EP, and EP-PROB. PROB (1 × 1010  CFU/mL) administration lasted 8 weeks and PE was induced on the 7th week by placing ligature on the animals' lower first molars. All animals were euthanized in the 9th week of the experiment. Biomolecular analyses, RT-PCR, and histomorphometric analyses were performed. The data obtained were analyzed statistically (ANOVA, Tukey, p < .05).

RESULTS

The EP group had higher dyslipidemia when compared to the C group, as well as higher levels of insulin resistance, proteinuria levels, percentages of systolic blood pressure, percentage of fatty hepatocytes in the liver, and expression of adipokines was up-regulated (LEPR, NAMPT, and FABP4). All these parameters (except insulin resistance, systolic blood pressure, LEPR and FABP4 gene expression) were reduced in the EP-PROB group when compared to the EP group. The EP group had lower villus height and crypt depth, as well as a greater reduction in Bacteroidetes and a greater increase in Firmicutes when compared to the EP-PROB group. Greater alveolar bone loss was observed in the EP group when compared to the EP-PROB group.

CONCLUSION

Bifidobacterium lactis HN019 can reduce the sequelae of EP in rats modulating intestinal parameters, attenuating expression of lipogenic genes and hepatic steatosis.

Preventive effects of Capparis Spinose extract on experimental periodontitis in rats: a histopathological and biochemical study

This study aimed to assess the effectiveness of Capparis Spinose (CS) in preventing the initiation and progression of experimental periodontitis and to evaluate the effect of its on systemic oxidative stress in rats by experimental periodontitis model. Twenty-four male rats were equally divided into; Ligatured (L), non-ligatured (NL), and Ligatured with CS (11 days/day per 20 mg/kg) (LC) groups. Experimental periodontitis was induced with the silk suture technic. Alveolar bone loss was examined, and total antioxidant capacity(TAOC), total oxidant status(TOS), and oxidative stress index(OSI) were analyzed in rat serum. Although; alveolar bone loss showed statistically significant lower values in the LC group compared to L (p < 0.05), not NL. In the LC group, osteoclast and osteoblast numbers were statistically significant compared to L, but there were no statistical differences between LC and NL. Serum TAOC levels were significantly lower in group L compared to others and also LC group showed significant differences from NL. TOS and OSI levels were significantly higher in group L than in other groups. Within the limitation of the present study, it can be said that the destruction via local inflammation that may occur after the experimental periodontitis can be prevented by using CS.

Ixeris dentata and Lactobacillus gasseri media protect against periodontitis through Nrf2-HO-1 signalling pathway

Periodontitis is an infectious inflammation in the gums characterized by loss of periodontal ligaments and alveolar bone. Its persistent inflammation could result in tooth loss and other health issues. Ixeris dentata (IXD) and Lactobacillus gasseri media (LGM) demonstrated strong antioxidant activity, which may prevent oxidative and inflammatory periodontitis. Here, IXD and LGM extracts were investigated for antioxidative activity against oral discomfort and evaluated for their synergistic effect against oxidative and inflammatory periodontitis in a mouse model. IXD/LGM suppressed pro-inflammatory cytokines like interleukin (IL)-1β, IL-6, and TNF-α. Additionally, it reduced pro-inflammatory mediators, nitric oxide, iNOS (inducible nitric oxide synthase), and COX-2 (cyclooxygenase-2) and enhanced AKT, Nrf2, and HO-1 activation. Similarly, IXD/LGM treatment elevated osteogenic proteins and mRNAs; alkaline phosphatase, collagen type 1 (COL1), osteopontin (OPN), and runt-related transcription factor 2 (RUNX2). Hematoxylin and Eosin (H&E) staining and micro-CT analysis confirm the positive impact of IXD/LGM on the periodontal structure and its associated inflammation. These findings demonstrate that IXD/LGM inhibits oxidative stress, periodontal inflammation, and its resultant alveolar bone loss in which Akt (also known as protein kinase B)-nuclear factor-erythroid 2-related factor 2 (Nrf2)-hemoxygenase-1 (HO-1) signaling is involved. Thus, IXD/LGM is a potential candidate against oxidative/inflammatory stress-associated periodontitis.

Protective effect of Chromobacterium violaceum and violacein against bone resorption by periodontitis

OBJECTIVES

The aim of this study was to evaluate the potential protective effect of Chromobacterium violaceum and violacein against periodontitis, in experimental models.

MATERIALS AND METHODS

A double-blind experimental study on the exposure to C. violaceum or violacein in experimentally ligature-induced periodontitis, as preventive factors against alveolar bone loss by periodontitis. Bone resorption was assessed by morphometry. Antibacterial potential of violacein was assessed in an in vitro assay. Its cytotoxicity and genotoxicity were evaluated using the Ames test and SOS Chromotest assay, respectively.

RESULTS

The potential of C. violaceum to prevent/limit bone resorption by periodontitis was confirmed. Daily exposure to 106 cells/ml in water intake since birth and only during the first 30 days of life significantly reduced bone loss from periodontitis in teeth with ligature. Violacein extracted from C. violaceum was efficient in inhibiting or limiting bone resorption and had a bactericidal effect against Porphyromonas gingivalis in the in vitro assay.

CONCLUSIONS

We conclude that C. violaceum and violacein have the potential to prevent or limit the progression of periodontal diseases, in an experimental model.

CLINICAL RELEVANCE

The effect of an environmental microorganism with potential action against bone loss in animal models with ligature-induced periodontitis represents the possibility of understanding the etiopathogenesis of periodontal diseases in populations exposed to C. violaceum and the possibility of new probiotics and antimicrobials. This would imply new preventive and therapeutic possibilities.

Economic Evaluations of Preventive Interventions for Dental Caries and Periodontitis: A Systematic Review

OBJECTIVES

To critically examine the methods used for full economic evaluations of preventive interventions for dental caries and periodontitis.

METHODS

Published literature post-2000 was searched to April 2021. Based on a developed intervention classification framework for dental caries and periodontitis, only universal, selective or indicated interventions were included in this review. The Drummond 10-point checklist was used for quality appraisal.

RESULTS

Of 3,007 unique records screened for relevance, 73 studies were reviewed. Most model-based studies (61/73) used cost-effectiveness analysis (49%) or cost-benefit analysis (28%). Trial-based studies (16/73) commonly used cost-effectiveness analysis (59%). Four studies used both economic evaluation methods. Sixty-four papers (88%) were on dental caries, eight papers (11%) focused on periodontitis, and one paper (1%) included both oral diseases; 72% of model-based and 82% of trial-based studies were of good quality. The most frequently investigated dental caries preventive interventions were water fluoridation (universal intervention; cost-saving or cost-effective), fissure sealant and fluoride varnish (selective and indicated interventions; cost-effectiveness outcomes were inconsistent). Supportive periodontal therapy with oral health education (indicated intervention; cost-effective) was the most frequently evaluated preventive intervention for periodontitis. Thirty percent of studies with a time horizon > 1 year did not apply an appropriate discount rate and 26% did not comprehensively discuss other important considerations beyond the technical analysis.

CONCLUSIONS

Generic health outcome measures should be incorporated for economic evaluations on preventive interventions for dental caries and periodontitis, and an increased focus to prevent periodontitis using economic evaluation methods is needed to inform resource allocation and policy decision-making.

Evaluation of the oxytocin effect in a rat model with experimental periodontitis

The aim of the present study was to evaluate the inhibitory effects of oxytocin on the development of periodontitis based on its properties against bone loss and resorption. Thirty-two Wistar albino rats were divided into four equal groups: control, periodontitis + saline, periodontitis + 0.5 mg/kg/day oxytocin, and periodontitis + 1 mg/kg/day oxytocin. Periodontitis groups received 4.0 silk ligatures around their cervixes of the right and left mandibular incisors in an "8" shape, kept for 14 days. Animals in oxytocin groups were injected once every day during 14 days with oxytocin. The mandibles were fixed and scanned using microcomputed tomography to quantify bone resorption and volumetric measurements. Blood samples were collected to analyze the concentrations of macrophage colony-stimulating factor (M-CSF), receptor activator of nuclear factor-κΒ ligand (RANKL), osteoprotegerin (OPG), matrix metalloproteinase-8 (MMP-8), tumor necrosis factor-alpha (TNF-α), interleukin (IL)-6, glutathione peroxidase (GPx), superoxide dismutase (SOD), and malondialdehyde (MDA). Histopathological evaluations were conducted to examine the gingiva and alveolar bone. Oxytocin prevented the development of periodontitis by decreasing ligament deteriorations and leukocytes in the gingival connective tissue and promoting reintegration with the alveolar bone. Bone resorption in all regions was less in the periodontitis + 1 mg/kg/day oxytocin group than in the periodontitis + saline group. Although TNF-α, IL-6, and RANKL values were lower in the periodontitis + 1 mg/kg/day oxytocin group, OPG was higher than that in the periodontitis + saline group. M-CSF, MMP-8, and MDA were lower in the oxytocin groups than in the periodontitis + saline group. Oxytocin may be an effective agent for periodontal diseases because it decreased bone resorption, oxidative stress, and inflammation in an experimental periodontitis.

Lactobacillus helveticus Prevents Periodontitis Induced by Aggregatibacter actinomycetemcomitans in Rats by Regulating β-Defensins

Objective

To study the preventive effect of Lactobacillus helveticus (L. helveticus) on periodontitis induced by Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) in rats.

Methods

Eighteen 8-week-old female rats were randomly divided into three groups: Sham group, Trehalose group, and L. helveticus SBT2171 (LH2171) group. We measured the distance of the cementoenamel junction-alveolar bone crest (CEJ-ABC) to evaluate alveolar bone resorption. Hematoxylin-eosin staining was used to observe the histopathological changes of rat hemimaxillary tissues. We detected the expression of β-defensins, tumor necrosis factor-α (TNF-α), interleukin- (IL-) 1β, and IL-6 and the number of A. actinomycetemcomitans in rat gingival tissues by quantitative reverse transcriptase polymerase chain reaction. The levels of IL-1β, IL-6, and TNF-α in rat gingival tissues were also measured by enzyme-linked immunosorbent assay.

Results

Compared with the Trehalose group, the distance of CEJ-ABC was prominently reduced and alveolar bone resorption was notably improved in the LH2171 group. And the infiltration of inflammatory cells in the hemimaxillary tissue decreased obviously, periodontal fibers were arranged neatly, connective tissue small blood vessels proliferated, and the number of A. actinomycetemcomitans reduced significantly in the LH2171 group. In addition, the mRNA expression and release of inflammatory factors in the gingival tissues in the LH2171 group were notably lower than those in the Trehalose group. On the 21st and 36th day, the expression of β-defensins in the gingival tissue of the LH2171 group increased significantly.

Conclusion

L. helveticus improves alveolar bone resorption and increases the expression of β-defensins thereby inhibiting the number of A. actinomycetemcomitans and thus prevents periodontitis.

Evaluation of the protective effects of non-thermal atmospheric plasma on alveolar bone loss in experimental periodontitis

OBJECTIVES

The inhibition of bone destruction is one of the main goals of periodontitis treatment. The aim of this study was to investigate the protective effects of non-thermal atmospheric plasma (NTAP) on alveolar bone loss radiographically, histomorphometrically, and histologically in experimental periodontitis in rats.

MATERIALS AND METHODS

A total of twenty-eight rats were randomly divided into three groups: control group (CG) (n = 8), periodontitis group (PG) (n = 10), and NTAP group (NTAPG) (n = 10). In PG and NTAPG, experimental periodontitis was created with ligating. The kINPen 11 plasma jet was applied around the ligatured teeth in NTAPG. The samples from each group were radiographically assessed with microcomputed tomography (micro-CT); then, histological (presence of osteoclasts and inflammatory cells) and immunohistochemical (immunoreactive of OCN and ALP) findings were compared.

RESULTS

The results revealed a significant increase in alveolar bone loss in the PG compared with CG and NTAPG (p < 0.05). Inflammation, alveolar resorption, and cement damage were reduced significantly in the group treated with NTAP compared to the PG (p < 0.05). Significantly higher levels of osteoclasts were detected in the PG in comparison with both CG and NTAPG (p < 0.05). The lowest osteocalcin and ALP values were determined in PG, and the differences between PG and both groups were also significant (p < 0.05).

CONCLUSION

Within the limitations of the present study, we can say that NTAP may enhance the bone remodeling process by inhibiting inflammation and preventing alveolar bone destruction.

CLINICAL RELEVANCE

NTAP has clinical potential for accelerating and treating periodontitis with the inflammatory response modulation, osteoblast differentiation, and alveolar bone loss reduction.

Improved oral hygiene care and chronic kidney disease occurrence: A nationwide population-based retrospective cohort study

Oral diseases or poor oral hygiene have close connections with systemic inflammatory reaction, which is one of major mechanism in the development of chronic kidney disease (CKD). We conducted a research assuming that better oral hygiene care would be negatively related with the risk of developing new-onset CKD.From 2003 to 2004, a total of 158,495 participants from the Korean national health insurance data sharing service which provides health screening data including variables as age, sex, vascular risk factors, medication information, indicators regarding oral hygiene, and laboratory results. The diagnosis of CKD and vascular risk factors were defined according to the International Statistical Classification of Diseases and Related Health Problems codes-10th revision. The follow-up period for the study subject was until the occurrence of CKD, until death, or Dec 31, 2015.Approximately 13.3% of the participants suffered from periodontal disease, and 40.7% brushed their teeth at least three times a day. With a median of 11.6 (interquartile range 11.3-12.2) years' follow-up, the cohort included 3223 cases of incident CKD. The 10-year incidence rate for CKD was 1.80%. In multivariable analysis with adjustment for age, sex, demographics, vascular risk factors, blood pressure, and blood laboratory results, frequent tooth brushing (≥3 times a day) was negatively related to occurrence of CKD (hazard ratio: 0.90, 95% confidence interval [0.83-0.99], P  =  .043, P value for trend  =  .043).Participants with improved oral hygiene (≥3 times a day) have showed less risk of CKD. Additional interventional studies are in need to establish causative relationship between oral hygiene and risk of CKD.

Local administration of ReveromycinA ointment suppressed alveolar bone loss in mice

ReveromycinA (RMA) was developed and is a unique agent for inhibiting osteoclast activity. In a previous study, we experimentally induced periodontal disease in a high-turnover osteoporosis osteoprotegerin-knockout mice (OPG KO) model and found that intraperitoneal administration of RMA inhibited alveolar bone resorption. We prepared a novel RMA-containing ointment for topical non-invasive administration in the oral cavity, in preparation for possible future clinical application. And we investigated whether this ointment can inhibit alveolar bone resorption in an experimental mouse model of periodontal disease. We examined wild-type (WT) and OPG KO mice ligated with wire around contact points on the left first and second molars to cause food impaction and induce experimental periodontal disease. RMA was administered three times a day. Using micro-computed tomography, we measured the volume of alveolar bone loss and also performed histological analysis. Our findings showed that localized administration of RMA containing ointment resulted in suppressed alveolar bone resorption, reduced osteoclast count, and lower immunostaining scores of inflammation sites compared with controls in both OPG KO and WT mice. Localized application of the specific osteoclast suppressor RMA in ointment form in the oral cavity could be a novel treatment for periodontitis that inhibits alveolar bone resorption locally.

Salvadora persica L. chewing stick and standard toothbrush as anti-plaque and anti-gingivitis tool: A systematic review and meta-analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Salvadora persica L. chewing stick, commonly known as miswak is still being used as an oral hygiene tool for plaque control and prevention against gingivitis. Various studies have reported on the therapeutics and prophylactic effects particularly on periodontal disease. This review aimed to evaluate the effectiveness of S. persica chewing stick compared to the standard toothbrush for anti-plaque and anti-gingivitis.

MATERIAL AND METHODS

A PRISMA-compliant systematic search of literature was done from the MEDLINE, CENTRAL, Science Direct, PubMed and Google Scholar. Literature that fulfilled eligibility criteria was identified. Data measuring plaque score and bleeding score were extracted. Qualitative and random-effects meta-analyses were conducted.

RESULTS

From 1736 titles and abstracts screened, eight articles were utilized for qualitative analysis, while five were selected for meta-analysis. The pooled effect estimates of SMD and 95% CI were -0.07 [-0.60 to 0.45] with an χ² statistic of 0.32 (p = 0.0001), I² = 80% as anti-plaque function and 95% CI were -2.07 [-4.05 to -0.10] with an χ² statistic of 1.67 (p = 0.02), I² = 82%.

CONCLUSION

S. persica chewing stick is a tool that could control plaque, comparable to a standard toothbrush. Further, it has a better anti-gingivitis effect and can be used as an alternative.

PHoral: Effects of carnosine supplementation on quantity/quality of oral salivae in healthy volunteer and in subjects affected by common oral pathologies

BACKGROUND

Diseases of the oral cavity (OC) with an infectious trigger such as caries and periodontal disease are extremely common in the general population and can also have effects at the cardiovascular level. The oral salivary flow, with its buffering capacity, is able to regulate the pH of the OC and, therefore, significantly contribute to the ecological balance of the microenvironment in which the oral microbiome (OM) develops. On the other side, when the quality/quantity of salivary flow is altered it is supposed the disruption of this balance with the potential increase in oral pathogens and triggered diseases. Among the endogenous substances able to exert a significant effect on the salivary flow and its characteristics, carnosine (Car), a dipeptide originally isolated in skeletal muscle, represents, thanks to the known buffering properties, a promising principle.

METHODS

We aimed this protocol to evaluate the quantitative/qualitative characteristics of the salivary flow in healthy volunteer subjects (n = 20) and in subjects suffering from common OC pathologies (n = 40), before and after 7 days of supplementation with SaliflussTM (Metis Healthcare srl, Milan, Italy), a Class I medical device on the market as 400 mg mucoadhesive oral tablets that has Car as the main ingredient.

DISCUSSION

Combining the characteristics of saliva with the OM and comparing them with OC pathologies, we expect to clarify their reciprocal relationship and, using quantitative proteomics techniques, to help clarify the mechanism of action of Car.

Effects of an oral hygiene regimen on progression of gingivitis/early periodontitis: A randomized controlled trial

BACKGROUND

Periodontal disease continues to be prevalent globally, but little clinical research has been undertaken to evaluate the long-term benefits of a daily oral hygiene regimen on progression of gingivitis/early periodontitis. The objective of this study was to evaluate the effects of an oral hygiene regimen (OHR) on the periodontal health of adults in good general health with established gingivitis and early periodontitis over 24 months.

METHODS

A randomized controlled trial was conducted in adults with established gingivitis, with isolated sites of probing pocket depth >4 mm. Study participants were randomized to the OHR (bioavailable stannous fluoride dentifrice, oscillating-rotating electric toothbrush, cetylpyridinium chloride rinse, and floss; P&G) or usual care products (sodium fluoride dentifrice and manual toothbrush; P&G) groups. At baseline and every 6 months, gingivitis and periodontal measures were assessed and a prophylaxis was conducted. The primary outcome was Gingival Bleeding Index-Bleeding Sites (GBI-BS). Analyses used ANCOVA at 5% significance levels.

RESULTS

A total of 107 individuals were enrolled; 87 completed the study. Mean GBI-BS, Modified Gingival Index, and Probing Pocket Depth (PPD) scores were significantly lower at each visit for the OHR versus usual care group by 28% to 39%, 12% to 18%, and 6% to 13%, respectively (p≤ 0.0009). The magnitude of reduction in median number of ≥2 mm PPD loss events for OHR versus the usual care group at 24 months was 74%.

CONCLUSION

Long-term use of the OHR produced significant periodontal health improvements versus the usual care products.

Association between toothbrushing and non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is considered the hepatic manifestation of metabolic syndrome. Periodontitis, as chronic inflammatory destructive disease, is associated metabolic syndromes bidirectionally. Toothbrushing is an essential and important way to manage periodontitis through mechanical removal of biofilm at periodontal tissue. We aimed to assess the association between toothbrushing frequency and the prevalent NAFLD in nationally representative Korean adults. Among adults aged 19 years and older who participated in the Korea National Health and Nutrition Examination Survey in 2010, a total of 6,352 subjects were analyzed. NAFLD was defined as fatty liver index ≥60. Multiple logistic regression analysis was used to estimate multivariable-adjusted odds ratios (ORs) and 95% confidence intervals (CIs). An inverse association between toothbrushing frequency and NAFLD was found. The adjusted ORs (95% CIs) of NALFD was 0.56 (0.35-0.91) in the group who performed toothbrushing ≥ 3 per day compared to the group that performed toothbrushing ≤ 1 per day. For those with toothbrushing frequency ≤1 per day, the adjusted OR (95% CIs) of NAFLD was 2.26 (1.22-4.19) in smokers and 4.52 (1.97-10.38) in subjects with diabetes mellitus (DM), compared to those without the disease and with toothbrushing frequency ≥2 per day, respectively. Our results indicate that higher frequency of toothbrushing is inversely associated with NAFLD. As a modifiable oral habit, regular toothbrushing may be recommended to lower risk of NAFLD, especially in high risk groups such as smokers and diabetic patients.

Crocin attenuates oxidative and inflammatory stress-related periodontitis in cardiac tissues in rats

BACKGROUND

Periodontitis, a chronic inflammatory disease affecting the supporting tissues around the teeth, causes significant inflammatory and oxidative changes in cardiac tissue. Crocin is the active constituent of Crocus sativus (saffron) which has antioxidant properties and is protective against cardiovascular disturbances.

OBJECTIVES

The present study aimed to investigate the protective effects of crocin on periodontitis-induced oxidative/inflammatory cardiac degeneration in rats in vivo.

MATERIAL AND METHODS

Thirty female Sprague Dawley rats were randomly divided into 3 groups: control group, periodontitis group (PD) and periodonditis plus crocin group (PD+Cr). Experimental periodontitis was induced by placing silk ligatures on the maxillary second molar teeth for 30 days. Afterward, crocin (100 mg/kg body weight/day) was administered to the PD+Cr group and saline was administered to the PD group and the control group for 15 days. The subjects were sacrificed on the 45th day.

RESULTS

Histological and biochemical analyses demonstrated that inducing periodontitis caused obvious damage to cardiac tissues which was significantly ameliorated by crocin (p < 0.05). Significant improvements in bone resorption parameters (cross-linked C-telopeptide of type I collagen and bone alkaline phosphatase) were also observed in the PD+Cr group (p < 0.05). In addition, crocin caused significant reductions of malondialdehyde levels and total oxidant score while antioxidant levels (glutathione, superoxide dismutase, total antioxidant score, and catalase) were significantly higher in PD+Cr group (p < 0.05).

CONCLUSIONS

This study reveals that periodontitis may cause oxidative damage in cardiac tissue and crocin improves periodontitis-induced degenerative changes in heart tissue, which is associated with its antioxidant properties.

Relationship between diabetes self-care practices and control of periodontal disease among type2 diabetes patients in Bangladesh

INTRODUCTION

The prevalence of periodontal disease is high in diabetes patients worldwide, including Bangladesh. Although associations of periodontal disease outcomes and clinical determinants of diabetes have been investigated, few studies have reported on the relationship between periodontal diseases outcomes with modifiable factors, such as self-care and oral hygiene practices, in patients with diabetes. Moreover, in order to develop targeted strategies, it is also important to estimate their aggregated contribution separately from that of the established sociodemographic and diabetics related clinical determinates. Therefore, this study was performed to elucidate 1) the relationship of diabetes patients' self-care and oral hygiene practices to periodontal disease and 2) the relative contributions of selected factors to periodontal disease outcome in type 2 diabetes patients.

METHODS

The data were obtained from the baseline survey of a multicentre, prospective cohort study. A total of 379 adult patients with type 2 diabetes from three diabetic centres in Dhaka, Rajshahi and Barishal, received periodontal examinations using the community periodontal index (CPI) probe, glycated haemoglobin examination, other clinical examinations, and structured questionnaires. Multiple logistics regression analyses were performed to assess the associations between selected factors and prevalence of any periodontal disease and its severity.

RESULTS

More than half of the participants were female (53.8%) and 66.8% of the total participants was 21-50 years old. The prevalence of any (CPI code 2+3+4; 75.7%) and severe form (CPI code 4; 35.1%) of periodontal disease were high in type 2 diabetes patients. In multivariate analysis, the odds of periodontal disease increased with unfavourable glycaemic control indicated by HbA1c ≥ 7%, and decreased by 64%, 85% and 92% with adherence to recommended diet, physical activity, and oral hygiene practices, respectively. Diabetes self-care practice explained the highest proportion of the variance (13.9%) followed by oral hygiene practices (10.9%) by modelling any periodontal disease versus no disease. Variables of diabetes conditions and oral hygiene practices explained 10.9% and 7.3% of the variance by modelling severe (CPI code 4) or moderate (CPI code 3) forms of periodontal disease versus mild form of periodontal disease. Findings also conferred that while poor diabetes control had an individually adverse association with any form of periodontal diseases and its severity, the risk of diseases was moderated by oral hygiene practices.

CONCLUSIONS

This study suggested that, in addition to diabetes-related clinical determinants, self-care practices, and oral hygiene practices must be taken into consideration for prevention and control of periodontal disease in patients with diabetes.

Preventing or controlling periodontitis reduces the occurrence of osteonecrosis of the jaw (ONJ) in rice rats (Oryzomys palustris)

INTRODUCTION

Osteonecrosis of the jaw (ONJ) is an adverse event that requires association of both systemic risk factors, such as powerful anti-resorptives (pARs; e.g. zoledronic acid [ZOL]), and local oral risk factors (e.g. tooth extraction, periodontitis). Whereas optimal oral health prior to initiate pARs is recognized as critically important for minimizing ONJ risk, the efficacy of preventive/maintenance measures in patients who are taking pARs is understudied. Rice rats fed a standard diet (STD), rich in insoluble fiber, develop localized periodontitis. STD-rats with localized periodontitis treated with ZOL for 18-24 wk develop ONJ. Hence, we hypothesized that controlling/preventing localized periodontitis in the ZOL-treated rats, reduces ONJ occurrence.

METHODS

We used two approaches to attempt reducing periodontitis prevalence: 1) periodontal cleaning (PC); and 2) replacing the STD-diet with a nutritionally-equivalent diet high in soluble fiber (SF). 75 four-week-old male rats were weight-randomized into five groups (n = 15) in a 24-week experiment. Three groups ate the STD-diet and two the high SF-diet. STD-diet groups received intravenous (IV) vehicle (VEH) q4wks (STD + VEH), 80 μg/kg ZOL q4wks IV (STD + ZOL), or ZOL plus PC q2wks (STD + ZOL + PC). The SF-diet groups received VEH (SF + VEH) or ZOL (SF + ZOL). Jaws were processed for histopathology and evaluated for ONJ prevalence and tissue-level periodontitis.

RESULTS

1) 40% of STD + VEH rats developed maxillary localized periodontitis with no ONJ; 2) 50% of STD + ZOL rats developed ONJ; 3) 7% of STD + ZOL + PC rats developed ONJ (p < 0.01 vs. STD + ZOL); and 4) one SF + ZOL rat developed localized periodontitis, and no SF + VEH or SF + ZOL rats developed ONJ (p < 0.001 vs. STD + ZOL).

CONCLUSIONS

1) Periodontal cleaning in ZOL-treated rats decreases localized periodontitis severity and reduces ONJ prevalence; and 2) feeding a SF-diet to ZOL-treated rats reduces both incidence of localized periodontitis and ONJ. Our data indicates strong oral microbial community shifts according to oral health condition and trends in the shifts associated with diet.

Exploratory Efficacy of Calcium-Vitamin D Milk Fortification and Periodontal Therapy on Maternal Oral Health and Metabolic and Inflammatory Profile

In this 2 × 2 factorial, outcome-assessor blinded, feasibility randomised trial we explored the effect of a non-pharmaceutical multi-component intervention on periodontal health and metabolic and inflammatory profiles among pregnant women with periodontitis receiving prenatal care in a Brazilian public health centre. 69 pregnant women (gestational age ≤20 weeks, T0) were randomly allocated into four groups: (1) fortified sachet (vitamin D and calcium) and powdered milk plus periodontal therapy during pregnancy (early PT) (n = 17); (2) placebo sachet and powdered milk plus early PT (n = 15); (3) fortified sachet and powdered milk plus late PT (after delivery) (n = 19); (4) placebo sachet and powdered milk plus late PT (n = 18). Third trimester (T1) and 6-8 weeks postpartum (T2) exploratory outcomes included periodontal health (% sites with bleeding on probing (BOP)), glucose, insulin, C-Reactive Protein, serum calcium and vitamin D. The mean BOP was significantly reduced in the early PT groups, while BOP worsened in the late PT groups. No significant effect of fortification on BOP was observed. Changes in glucose levels and variation on birthweight did not differ among groups This feasibility trial provides preliminary evidence for estimating the minimum clinically important differences for selected maternal outcomes. A large-scale trial to evaluate the interventions' clinical benefits and cost-effectiveness is warranted.

Oral microbiome and pregnancy: A bidirectional relationship

The oral cavity contains the second most complex microbial population within the human body, with more than 700 bacterial organisms. Recent advances in Next Generation Sequencing technology have unraveled the complexities of the oral microbiome and provided valuable insights into its role in health and disease. The human oral microbiome varies dramatically during the different stages of life, including pregnancy. The total viable microbial counts in pregnant women are known to be higher compared to non-pregnant women, especially in the first trimester of pregnancy. A balanced oral microbiome is vital for a healthy pregnancy, as perturbations in the oral microbiome composition can contribute to pregnancy complications. On the other hand, physiological changes and differences in hormonal levels during pregnancy, increase susceptibility to various oral diseases such as gingivitis and periodontitis. A growing body of evidence supports the link between the composition of the oral microbiome and adverse pregnancy outcomes such as preterm birth, preeclampsia, low birth weight among others. This review aims to summarize the dynamics of oral microbiome during pregnancy and to discuss the relationship between a dysbiotic oral microbiome and pregnancy complications.

Anti-inflammatory effect of IL-1ra-loaded dextran/PLGA microspheres on Porphyromonas gingivalis lipopolysaccharide-stimulated macrophages in vitro and in vivo in a rat model of periodontitis

Periodontitis is a multifactorial chronic infectious disease leading to a host immune response involving inflammatory cytokines, especially IL-1β, which is the main reason for further developing this disease. IL-1 receptor antagonist (IL-1ra) binds IL-1 receptor, inhibiting IL-1β signaling and reducing the levels of other cytokines closely related to periodontitis, such as IL-6 and TNF-α. Therefore, the use of IL-1ra to inhibit periodontitis development in a system, ensuring its sustained release, might be an effective way to combat this disease. Hence, in this study, a novel IL-1ra-loaded dextran/PLGA microsphere was developed to allow the sustained release of IL-1ra and enhance the anti-inflammatory properties. Therefore, this study's purposes were to develop a novel periodontal treatment for inhibition and treatment of periodontitis and evaluate the sustained-release effect and anti-inflammatory properties of IL-1ra-loaded dextran/PLGA microspheres in vitro by cell experiments and in vivo by animal experiments. The results showed that IL-1ra-loaded dextran/PLGA microspheres were non-toxic both in vitro and in vivo and could be used as a safe and effective treatment. In addition, these microspheres could significantly prolong the half-life of IL-1ra drug, exerting a useful anti-inflammatory effect in macrophages stimulated with P. gingivalis lipopolysaccharide and in rats with periodontitis. In conclusion, IL-1ra-loaded dextran/PLGA microsphere might be a useful tool to combat periodontal disease.

Proanthocyanidins and Flavan-3-ols in the Prevention and Treatment of Periodontitis-Immunomodulatory Effects, Animal and Clinical Studies

This paper continues the systematic review on proanthocyanidins and flavan-3-ols in the prevention and treatment of periodontal disease and covers the immunomodulatory effects, and animal- and clinical studies, while the other part discussed the direct antibacterial properties. Inflammation as a major response of the periodontal tissues attacked by pathogenic microbes can significantly exacerbate the condition. However, the bidirectional activity of phytochemicals that simultaneously inhibit bacterial proliferation and proinflammatory signaling can provide a substantial alleviation of both cause and symptoms. The modulatory effects on various aspects of inflammatory and overall immune response are covered, including confirmed and postulated mechanisms of action, structure activity relationships and molecular targets. Further, the clinical relevance of flavan-3-ols and available outcomes from clinical studies is analyzed and discussed. Among the numerous natural sources of flavan-3-ols and proanthocyanidins the most promising are, similarly to antibacterial properties, constituents of various foods, such as fruits of Vaccinium species, tea leaves, grape seeds, and tannin-rich medicinal herbs. Despite a vast amount of in vitro and cell-based evidence of immunomodulatory there are still only a few animal and clinical studies. Most of the reports, regardless of the used model, indicated the efficiency of these phytochemicals from cranberries and other Vaccinium species and tea extracts (green or black). Other sources such as grape seeds and traditional medicinal plants, were seldom. In conclusion, the potential of flavan-3-ols and their derivatives in prevention and alleviation of periodontal disease is remarkable but clinical evidence is urgently needed for issuing credible dietary recommendation and complementary treatments.

Kgp DNA Vaccine Prevents Experimental Periodontitis

PURPOSE

To investigate the prophylactic effect of lysine-specific protease (Kgp) vaccine on experimental periodontitis in mice.

MATERIALS AND METHODS

We constructed the eukaryotic expression plasmid pVAX1-kgp and immunised mice with the recombinant plasmid. Mice were divided into two groups and immunised with pVAX1-kgp or pVAX1 three times at 2-week intervals. Immunoglobulin (Ig)G, IgG1 and IgG2a antibodies were detected by enzyme-linked immunosorbent assay (ELISA) before and after immunisation. At the last immunisation, a silk ligature infiltrated with Porphyromonas gingivalis (P. gingivalis) was tied at the neck of the maxillary second molar to induce experimental periodontitis. Each group was euthanised after 10 days, and microcomputed tomography (micro-CT) and hematoxylin-eosin (HE) staining were used to detect the loss of alveolar bone.

RESULTS

Comparison with the pVAX1 group indicated that mice immunised with Kgp had higher levels of IgG (P < 0.05); the levels of the IgG1 were statistically significantly different (p < 0.05), and the levels of the IgG2a subtype were not significantly different. The results of micro-CT and HE staining showed that the alveolar bone loss in the pVAX1-kgp group was statistically significantly less than that in the pVAX1 group (p < 0.05). The expression of the related inflammatory factors, including interleukin-1β (IL-β), tumour necrosis factor (TNF-α) and interleukin-6 (IL-6), was lower in the pVAX1-kgp group than in the pVAX1 group.

CONCLUSION

The Kgp DNA vaccine can enhance IgG levels in a model of experimental periodontitis, effectively activate immunity, and mitigate alveolar bone loss.

A public health approach for prevention of periodontal disease

Upwards of 1 in 10 adults worldwide may be affected by severe periodontitis, making the disease more prevalent than cardiovascular disease. Despite its global scope, its impact on pain, oral function, and the wellbeing of individuals, and the disproportionate burden of disease and the socioeconomic impact on communities, the perception that periodontal disease is a public health problem remains low. Although there have been substantial improvements in our understanding of the etiology of periodontal disease and how we can prevent and control it, these advances have been primarily focused on individual, patient-focused approaches. The prevention of periodontal disease depends on improving currently available individual interventions and on determining what public health interventions can be effective and sustainable under real-life conditions. Currently, public health approaches for periodontal disease prevention and control are lacking. This review traces the historical strategies for prevention of periodontal disease in an epidemiologic transition context, using a modified model developed for cardiovascular disease, and presents a possible public health approach. Improving periodontal disease prevention and control will need to take into consideration the core activities of a public health approach: assessment, policy development, and assurance.

Systemic treatment with alpha-tocopherol and/or sodium selenite decreases the progression of experimental periodontitis

OBJECTIVE

To investigate the effects of sodium selenite (Se) and/or α-tocopherol (αT) applications on the alveolar bone loss (ABL), the number of gingival collagen fibers, inducible nitric oxide synthase (iNOS)+ and CD95+ cell numbers, and serum cytokine concentrations in experimental periodontitis in rats.

MATERIALS AND METHODS

Forty Sprague Dawley rats were divided into four groups of ten as follows: group A: Se group, group B: αT group, group C: Se and αT combined group, and group D: control group (intraperitoneal (IP) saline injection applied). Using the image analysis method in the connective tissue under the connective epithelium, the numbers of iNOS, CD95 positive cells, and collagen fibers were counted. ELISA kits were used to test the concentrations of serum interleukin (IL)-1β, IL-6, and IL-4.

RESULTS

The combination of Se and αT (group C) suppressed ABL compared with the control group (group D) (P < 0.05). In group A (Se), the number of iNOS+ cells was smaller than in group D (P < 0.05).

CONCLUSION

Se has been concluded to inhibit inflammation of the gum due to iNOS. Se and αT can have a remarkable important role in preventing alveolar bone loss, and particularly in combination.

CLINICAL RELEVANCE

Se and/or αT application may be useful in preventing the destruction of periodontal tissue and treatment of periodontal disease.

Signs of alveolar bone damage in early stages of periodontitis and its prevention by stimulation of cannabinoid receptor 2. Model in rats

The aims of the present study were, first, to identify signs of alveolar bone damage in early stages of experimental periodontitis (EP) and, second, to assess its possible prevention by treatment with cannabinoid receptor 2 agonist HU 308. Experimental periodontitis was induced by injections of lipopolysaccharide (LPS) (1mg/ml) in gums surrounding maxillary and mandibular first molar, 3 days per week, and untreated controls were kept for comparison. Then, a 3-week study was conducted including eighteen new rats (six rats per group): 1) controls; 2) experimental periodontitis rats; and 3) experimental periodontitis rats treated daily with HU 308 (500 ng/ml). After euthanasia, alveolar bone loss was assessed by morphometric and histomorphometric techniques, and the content of prostaglandin E2 (PGE2) in gingival tissue was evaluated by radioimmunoassay. The first signs of alveolar bone loss were apparent at 3 weeks of experimental periodontitis (ρ<0.05) in the mandibular first molar, but there was no detectable change at 1 week, leading us to establish 3 weeks as an early stage of experimental periodontitis. Rats subjected to 3-week experimental periodontitis showed less interradicular bone volume, less whole bone perimeter and fewer bone formation areas, and higher periodontal space height, bone resorption areas, number of osteoclasts and gingival content of prostaglandin E2 than controls, while HU 308 prevented, at least partially, the deleterious effects (ρ<0.001). We can conclude that a 3-week term of lipopolysaccharide-induced periodontitis in rats provides a valid model of the early stage of the disease, as emerging damage is observed in bone tissue. Furthermore, harmful effects at 3 weeks could be prevented by local stimulation of cannabinoid receptor 2, before greater damage is produced.

Impact of hyperglycemia and treatment with metformin on ligature-induced bone loss, bone repair and expression of bone metabolism transcription factors

This study evaluated the influence of type 2 diabetes mellitus on bone loss, bone repair and cytokine production in hyperglycemic rats, treated or not with metformin. The animals were distributed as follow: Non-Hyperglycemic (NH), Non Hyperglycemic with Ligature (NH-L), Treated Non Hyperglycemic (TNH), Treated Non Hyperglycemic with Ligature Treated (TNH-L), Hyperglycemic (H), Treated Hyperglycemic (TH), Hyperglycemic with Ligature (H-L), Treated Hyperglycemic with Ligature (TH-L). At 40th day after induction of hyperglycemia, the groups NH-L, TNH-L, H-L, TH-L received a ligature to induce periodontitis. On the 69th, the TNH, TNH-L, TH, TH-L groups received metformin until the end of the study. Bone repair was evaluated at histometric and the expression levels of Sox9, RunX2 and Osterix. Analysis of the ex-vivo expression of TNF-α, IFN-γ, IL-12, IL-4, TGF-β, IL-10, IL-6 and IL-17 were also evaluated. Metformin partially reverse induced bone loss in NH and H animals. Lower OPG/RANKL, increased OCN and TRAP expression were observed in hyperglycemic animals, and treatment with metformin partially reversed hyperglycemia on the OPG/RANKL, OPN and TRAP expression in the periodontitis. The expression of SOX9 and RunX2 were also decreased by hyperglycemia and metformin treatment. Increased ex vivo levels of TNF-α, IL-6, IL-4, IL-10 and IL-17 was observed. Hyperglycemia promoted increased IL-10 levels compared to non-hyperglycemic ones. Treatment of NH with metformin was able to mediate increased levels of TNF-α, IL-10 and IL-17, whereas for H an increase of TNF-α and IL-17 was detected in the 24- or 48-hour after stimulation with LPS. Ligature was able to induce increased levels of TNF-α and IL-17 in both NH and H. This study revealed the negative impact of hyperglycemia and/or treatment with metformin in the bone repair via inhibition of transcription factors associated with osteoblastic differentiation.

Vitamin D and Periodontitis: A Systematic Review and Meta-Analysis

To explore the vitamin D levels of periodontitis patients in comparison with periodontally healthy ones, and to assess the influence of vitamin D supplementation as an adjunctive during nonsurgical periodontal treatment (NSPT). Five databases (Pubmed, Embase, Scholar, Web of Sciences, and Cochrane Library) were searched until May 2020. Mean difference (MD) meta-analysis with corresponding 95% confidence interval (95% CI) and sensitivity tests via meta-regression were used. We followed Strength of Recommendation Taxonomy (SORT) to appraise the strength and quality of the evidence. Sixteen articles were included, fourteen case-control and two intervention studies, all reporting 25-hydroxyvitamin D (25(OH)D) levels. Compared with the healthy controls, the circulating 25(OH)D levels were significantly lower in chronic periodontitis patients (pooled MD = −6.80, 95% CI: −10.59 to −3.02). Subgroup analysis revealed differences among 25(OH)D measurements, with liquid chromatography-mass spectrometry being the most homogeneous method (pooled MD = −2.05, 95% CI: −3.40 to −0.71). Salivary levels of 25(OH)D showed no differences between groups. Due to the low number of studies, conclusions on aggressive periodontitis and in the effect of vitamin D supplementation after NSPT were not possible to ascribe. Compared with healthy controls, 25(OH)D serum levels are significantly lower in chronic periodontitis patients, with an overall SORT A recommendation. Future studies are needed to clarify the effect of vitamin D supplementation and the biological mechanisms linking vitamin D to the periodontium.

Emerging Applications of Drug Delivery Systems in Oral Infectious Diseases Prevention and Treatment

The oral cavity is a unique complex ecosystem colonized with huge numbers of microorganism species. Oral cavities are closely associated with oral health and sequentially with systemic health. Many factors might cause the shift of composition of oral microbiota, thus leading to the dysbiosis of oral micro-environment and oral infectious diseases. Local therapies and dental hygiene procedures are the main kinds of treatment. Currently, oral drug delivery systems (DDS) have drawn great attention, and are considered as important adjuvant therapy for oral infectious diseases. DDS are devices that could transport and release the therapeutic drugs or bioactive agents to a certain site and a certain rate in vivo. They could significantly increase the therapeutic effect and reduce the side effect compared with traditional medicine. In the review, emerging recent applications of DDS in the treatment for oral infectious diseases have been summarized, including dental caries, periodontitis, peri-implantitis and oral candidiasis. Furthermore, oral stimuli-responsive DDS, also known as "smart" DDS, have been reported recently, which could react to oral environment and provide more accurate drug delivery or release. In this article, oral smart DDS have also been reviewed. The limits have been discussed, and the research potential demonstrates good prospects.

Oral status and aesthetics after nonsurgical periodontal treatment: Do patient's perception and dentist's evaluation agree?

Objectives

Periodontal healing is often accompanied by side effects, which may cause an aesthetic deficit. The present investigation was focussed to compare patient's subjective perception of their posttherapy aesthetics with the objective measures of the results.

Materials and methods

Survey results from patients (subjective parameters) on oral status and aesthetics were compared against routine clinical parameters and corresponding survey results from treating dentists (objective parameters), both before and after periodontal treatment. Subjective outcome parameters were then suitably transformed and compared with the objective ones to investigate the agreement between patients' perception and actual outcomes.

Results

Objective recordings of periodontal status by the dentist and subjective awareness of the patient are quite contradictory to each other for almost all participants. Further, it was found that their aesthetics in the front were better after treatment, but dentist professionals targeted for future treatment needs.

Conclusions

In this study, it was found that patients improved aesthetically on the upper jaw front after the therapy, which was not shared by the dentists. This discrepancy was due to the clinicians' view on more aesthetic corrective procedures than on patients' need.

The dental anomaly: how and why dental caries and periodontitis are phenomenologically atypical

BACKGROUND

Despite their shared origins, medicine and dentistry are not always two sides of the same coin. There is a long history in medical philosophy of defining disease and various medical models have come into existence. Hitherto, little philosophical and phenomenological work has been done considering dental caries and periodontitis as examples of disease and illness.

METHODS

A philosophical methodology is employed to explore how we might define dental caries and periodontitis using classical medical models of disease - the naturalistic and normativist. We identify shared threads and highlight how the features of these highly prevalent dental diseases prevent them fitting in either definition. The article describes phenomenology and the current thought around the phenomenology of illness, exploring how and why these dental illnesses might integrate into a phenomenological model.

RESULTS

We discover that there are some features particular to dental caries and periodontitis: ubiquity, preventability and hyper-monitorablility. Understanding the differences that these dental diseases have compared to many other classically studied diseases leads us to ethical questions concerning how we might manage those who have symptoms and seek treatment. As dental caries and periodontitis are common, preventable and hyper-monitorable, it is suggested that these features affect the phenomenology of these illnesses. For example, if we experience dental illness when we have consciously made decisions that have led to it, do we experience them differently to those rarer illnesses that we cannot expect? Other diseases share these features are discussed.

CONCLUSIONS

This paper highlights the central differences between the classical philosophical notion of disease in medicine and the dental examples of caries and periodontitis. It suggests that a philosophical method of conceptualising medical illness - phenomenology - should not be applied to these dental illnesses without thought. A phenomenological analysis of any dental illness is yet to be done and this paper highlights why a separate strand of phenomenology should be explored, instead of employing those that are extant. The article concludes with suggestions for further research into the nascent field of the phenomenology of dental illness and aims to act as a springboard to expose the dental sphere to this philosophical method of analysis.

The Significance of Lactoperoxidase System in Oral Health: Application and Efficacy in Oral Hygiene Products

Lactoperoxidase (LPO) present in saliva are an important element of the nonspecific immune response involved in maintaining oral health. The main role of this enzyme is to oxidize salivary thiocyanate ions (SCN^-) in the presence of hydrogen peroxide (H₂O₂) to products that exhibit antimicrobial activity. LPO derived from bovine milk has found an application in food, cosmetics, and medical industries due to its structural and functional similarity to the human enzyme. Oral hygiene products enriched with the LPO system constitute an alternative to the classic fluoride caries prophylaxis. This review describes the physiological role of human salivary lactoperoxidase and compares the results of clinical trials and in vitro studies of LPO alone and complex dentifrices enriched with bovine LPO. The role of reactivators and inhibitors of LPO is discussed together with the possibility of using nanoparticles to increase the stabilization and activity of this enzyme.

Acceptance of a tongue vacuum cleaner among children and evaluation of tongue cleaning at home

The anaerobic microenvironment of the grooved tongue surface provides optimal conditions for the survival of microorganisms. These microbes may promote caries, periodontitis marginalis, periimplantitis as well as halitosis. A new device, the TS1 tongue vacuum cleaner, is designed to remove bacterial biofilm from the tongue’s surface. The aim of the present study was to both examine the acceptance of this tongue vacuum cleaner by children at the School Dental Clinic Basel as compared to a child’s manual tooth brush, and tongue cleaning at home for a 1-month period. This study did not investigate the cleaning effect. One hundred and sixty-two children aged 5 to 18 years participated in this study. The acceptance of the tongue vacuum cleaner was significantly higher with 8.9 cm on the visual analogue scale (VAS) (0–10 cm) in comparison to a child’s manual tooth brush with 7.8 cm (p < 0.001). After professional tongue cleaning, the children were asked to clean their tongues at home for a 1-month period, and to return a completed questionnaire (n = 66). The children estimated their acceptance of daily tongue cleaning with 8.3 cm on the VAS, their parents with 8.7 cm. Fifty eight children reported willingness to continue cleaning their tongues at home after the 1-month examination time. The data show that the use of the tongue vacuum cleaner, as part of a professional oral prophylaxis, is well accepted by children and may help promote, along with professional instruction, home tongue cleaning on a regular basis.

Systemic effects of periodontitis treatment in patients with type 2 diabetes: a 12 month, single-centre, investigator-masked, randomised trial

BACKGROUND

Chronic inflammation is believed to be a major mechanism underlying the pathophysiology of type 2 diabetes. Periodontitis is a cause of systemic inflammation. We aimed to assess the effects of periodontal treatment on glycaemic control in people with type 2 diabetes.

METHODS

In this 12 month, single-centre, parallel-group, investigator-masked, randomised trial, we recruited patients with type 2 diabetes, moderate-to-severe periodontitis, and at least 15 teeth from four local hospitals and 15 medical or dental practices in the UK. We randomly assigned patients (1:1) using a computer-generated table to receive intensive periodontal treatment (IPT; whole mouth subgingival scaling, surgical periodontal therapy [if the participants showed good oral hygiene practice; otherwise dental cleaning again], and supportive periodontal therapy every 3 months until completion of the study) or control periodontal treatment (CPT; supra-gingival scaling and polishing at the same timepoints as in the IPT group). Treatment allocation included a process of minimisation in terms of diabetes onset, smoking status, sex, and periodontitis severity. Allocation to treatment was concealed in an opaque envelope and revealed to the clinician on the day of first treatment. With the exception of dental staff who performed the treatment and clinical examinations, all study investigators were masked to group allocation. The primary outcome was between-group difference in HbA_1c at 12 months in the intention-to-treat population. This study is registered with the ISRCTN registry, number ISRCTN83229304.

FINDINGS

Between Oct 1, 2008, and Oct 31, 2012, we randomly assigned 264 patients to IPT (n=133) or CPT (n=131), all of whom were included in the intention-to-treat population. At baseline, mean HbA_1c was 8·1% (SD 1·7) in both groups. After 12 months, unadjusted mean HbA_1c was 8·3% (SE 0·2) in the CPT group and 7·8% (0·2) in the IPT group; with adjustment for baseline HbA_1c, age, sex, ethnicity, smoking status, duration of diabetes, and BMI, HbA_1c was 0·6% (95% CI 0·3-0·9; p<0·0001) lower in the IPT group than in the CPT group. At least one adverse event was reported in 30 (23%) of 133 patients in the IPT group and 23 (18%) of 131 patients in the CPT group. Serious adverse events were reported in 11 (8%) patients in the IPT group, including one (1%) death, and 11 (8%) patients in the CPT group, including three (2%) deaths.

INTERPRETATION

Compared with CPT, IPT reduced HbA_1c in patients with type 2 diabetes and moderate-to-severe periodontitis after 12 months. These results suggest that routine oral health assessment and treatment of periodontitis could be important for effective management of type 2 diabetes.

FUNDING

Diabetes UK and UK National Institute for Health Research.