The influence of an anti-inflammatory diet on gingivitis. A randomized controlled trial

Effects of a Non-Energy-Restricted Ketogenic Diet on Clinical Oral Parameters. An Exploratory Pilot Trial

Ketogenic diets (KDs) may be a helpful complement in the prevention of and therapy for several diseases. Apart from their non-cariogenic properties, it is still unclear how KDs affect oral parameters. The aim of this study was to investigate the influence of a KD on clinical periodontal parameters. Twenty generally healthy volunteers with an average age of 36.6 years underwent a KD for 6 weeks. Their compliance was monitored by measuring their urinary ketones daily and by keeping 7-day food records. Clinical oral parameters included plaque (PI), gingival inflammation (GI), a complete periodontal status (probing depths, bleeding on probing), and general physical and serologic parameters at baseline and after 6 weeks. The results showed a trend towards lower plaque values, but with no significant changes from baseline to the end of the study with regard to the clinical periodontal parameters. However, their body weight and BMI measurements showed a significant decrease. The regression analyses showed that the fat mass and the BMI were significantly positively correlated to periodontal inflammation, while HDL, fiber, and protein intake were negatively correlated to periodontal inflammation. The KD change did not lead to clinical changes in periodontal parameters in healthy participants under continued oral hygiene, but it did lead to a significant weight loss.

Effect of the Mediterranean diet on gingivitis: A randomized controlled trial

AIM

This study aimed to investigate the effects of a 6-week Mediterranean diet (MD) intervention on gingival inflammatory and anthropometric parameters of patients with gingivitis.

MATERIALS AND METHODS

Forty-two participants were allocated to MD group (MDG) or control group (CG). After a 2-week equilibration period regarding dental care procedures, only MDG changed their diet to MD for 6 weeks, supported by a diet counselling. Gingival and anthropometric parameters were assessed at baseline (T0), Week 2 (T1, beginning of MD intervention), and Week 8 (T2). Adherence to MD was assessed by the Mediterranean Diet Adherence Screener (MEDAS); dietary behaviour was evaluated by the German Health Interview and Examination Survey for Adults Food Frequency Questionnaire (DEGS-FFQ).

RESULTS

Plaque values remained constant in both groups. Inflammatory periodontal and anthropometric parameters decreased in the MDG only (gingival index: T1 1.51 ± 0.21, T2 1.49 ± 0.24; bleeding on probing: T1 51.00 ± 14.65, T2 39.93 ± 13.74; body weight: T1 79.01 ± 15.62, T2 77.29 ± 17.00; waist circumference: T1 84.41 ± 10.1, T2 83.17 ± 10.47 (p < .05). MEDAS revealed a sufficient diet adherence for MDG.

CONCLUSION

Within this study, gingival inflammatory parameters were significantly reduced by MD, whereas plaque parameters remained constant. The diet counselling achieved sufficient adherence with beneficial changes in weight loss and waist circumference.

Psychopathologies and socioeconomic status as risk indicators for periodontitis: a survey-based investigation in German dental practices

OBJECTIVES

Periodontitis is a highly prevalent multifactorial disease associated with various mental disorders. However, study results about this association are still contradictory. One methodological reason could be the neglect of potential confounders, such as socioeconomic factors or mental comorbidity. Our study examined a wide range of potential psychosocial risk indicators to identify those with relevant associations to periodontitis.

MATERIALS AND METHODS

In a cross-sectional study, 111 patients with periodontitis (PERIO) (> 30% teeth with approximal attachment loss ≥ 5 mm) and 110 patients without periodontitis (NON-PERIO) were recruited in four dental practices in Germany. Clinical attachment loss, pocket depth, plaque, bleeding on probing, and DMFT were measured. Psychopathologic symptoms and socioeconomic status were recorded using self-report questionnaires (DAS, PHQ-8, GAD-7, CTS, SCOFF, AUDIT, FTND, SSS-8, SES).

RESULTS

The PERIO group reported significantly lower socioeconomic status (Cohen's d = 0.49) and higher psychopathological symptom burden than the NON-PERIO regarding dental anxiety (d = 0.86) and avoidance behavior, nicotine dependency (d = 0.84), depressiveness (d = 0.46), general anxiety (d = 0.45), somatic symptoms (d = 0.42), and childhood traumatization (d = 0.34). No significant group differences existed for alcohol abuse and eating disorders. Dental anxiety was the strongest predictor of periodontitis and showed significant correlations with other psychopathologies and social status.

CONCLUSIONS

Out of all psychosocial factors, socioeconomic status and dental anxiety showed the greatest association with periodontitis.

CLINICAL RELEVANCE

Dentists should encourage socially disadvantaged and dentally anxious patients in the utilization of prevention and dental care. Furthermore, physicians and psychotherapists can contribute to the early detection of dental anxiety, oral diseases, and avoidance behavior.

Waistline to the gumline: Relationship between obesity and periodontal disease-biological and management considerations

Obesity is a pandemic and periodontitis is the sixth most prevalent disease in the world. These two noncommunicable diseases share several risk determinants. Epidemiologic evidence from the last 2 decades has established an increase in periodontitis prevalence in obese and overweight individuals. Biologic mechanisms potentially linking obesity and periodontal disease are adiposity-associated hyperinflammation, microbial dysbiosis, altered immune response, specific genetic polymorphisms, and increased stress. However, because of the lack of longitudinal interventional studies and randomized clinical trials, there is insufficient evidence to determine the cause-effect relationship between these two diseases. Despite this, the negative impact of obesity on oral health is well established. Several logistic and physiologic complications are associated with treating obese patients in a dental setting, and it requires an interprofessional team approach. Oral health care professionals need to be aware of the specific management considerations while rendering for this cohort, including modified practice facility and equipment, tailored supportive periodontal therapy, and heightened precaution during conscious sedation and surgical procedures.

Investigation of direct and indirect association of ultra-processed food intake and periodontitis

BACKGROUND

Ultra-processed foods are associated with both sugar intake and non-communicable diseases. We aimed to assess whether the intake of ultra-processed food is associated with periodontal disease and whether this association, if present, is dependent on non-communicable diseases.

METHODS

This analysis used data from cycles 2009 to 2010, 2011 to 2012, and 2013 to 2014 of the National Health and Nutrition Examination Survey (NHANES), including participants aged 30 years or older. Dietary recalls were categorized according to the NOVA classification, and total contribution of ultra-processed foods to daily energy intake (%E) was calculated. Cases of periodontitis were defined as moderate or severe according to the CDC working group criteria for use in population surveillance of periodontitis. Adjustment variables to estimate total and direct associations were defined with directed acyclic graphs. Odds ratios were estimated with logistic regression for moderate/severe periodontitis and severe periodontitis, and ordinal logistic regression for the trichotomized outcome. Analyses were performed using NHANES fasting subsample weights.

RESULTS

Sample participants numbered 4809 (52.2% female), with a mean age of 52.1 years (SE, 0.3). The prevalence of periodontal disease was 27.8% for moderate and 6.5% for severe cases. Mean %E from ultra-processed foods was 54.4 (SE, 0.5). No significant crude, direct, or total association between ultra-processed %E and periodontal disease was found.

CONCLUSION

Intake of ultra-processed foods is not associated with periodontal disease in US non-institutionalized adults over 30 years old, whether directly or by mediation.

Dietary inflammatory potential is associated with poor periodontal health: A population-based study

Aim

To investigate the association between dietary inflammatory potential and poor periodontal health.

Material and Methods

A cross‐sectional analysis of a nationally representative sample of participants was performed. NHANES 2011–2014 (n = 7081) and NHANES 2001–2004 (n = 5098) were used as discovery and validation datasets, respectively. The energy‐adjusted dietary inflammatory index (E‐DII) score was calculated for each participant based on 24‐h dietary recalls to assess diet‐associated inflammation. Periodontitis was defined by the CDC/AAP using clinical periodontal parameters. Natural cubic spline was applied to identify any non‐linear associations of the E‐DII score with moderate/severe periodontitis. Furthermore, interaction analyses were performed by age, gender, and race/ethnicity to explore the moderating roles of these factors.

Results

In the discovery dataset, a non‐linear positive relationship with periodontitis was identified for the E‐DII score (p_{non‐linearity} < .001) after adjustment for potential confounders. Compared with those individuals in the lowest tertile of E‐DII, participants in the highest tertile who consumed a pro‐inflammatory diet were 53% more likely to be periodontitis (OR _tertile3vs1 = 1.53, 95% CI: 1.33–1.77). The validation dataset showed similar associations. Relatively stronger associations were seen in older adults and males.

Conclusion

Consuming a pro‐inflammatory diet indicated by the E‐DII score is associated with periodontal disease in the U.S. general adult population.

Identification of Gingivitis-Related Genes Across Human Tissues Based on the Summary Mendelian Randomization

Periodontal diseases are among the most frequent inflammatory diseases affecting children and adolescents, which affect the supporting structures of the teeth and lead to tooth loss and contribute to systemic inflammation. Gingivitis is the most common periodontal infection. Gingivitis, which is mainly caused by a substance produced by microbial plaque, systemic disorders, and genetic abnormalities in the host. Identifying gingivitis-related genes across human tissues is not only significant for understanding disease mechanisms but also disease development and clinical diagnosis. The Genome-wide association study (GWAS) a commonly used method to mine disease-related genetic variants. However, due to some factors such as linkage disequilibrium, it is difficult for GWAS to identify genes directly related to the disease. Hence, we constructed a data integration method that uses the Summary Mendelian randomization (SMR) to combine the GWAS with expression quantitative trait locus (eQTL) data to identify gingivitis-related genes. Five eQTL studies from different human tissues and one GWAS studies were referenced in this paper. This study identified several candidates SNPs and genes relate to gingivitis in tissue-specific or cross-tissue. Further, we also analyzed and explained the functions of these genes. The R program for the SMR method has been uploaded to GitHub(https://github.com/hxdde/SMR).

Association between Dietary Inflammatory Index and Periodontitis: A Cross-Sectional and Mediation Analysis

Inflammation-modulating elements are recognized periodontitis (PD) risk factors, nevertheless, the association between dietary inflammatory index (DII) and PD has never been appraised. We aimed to assess the association between DII and PD and the mediation effect of DII in the association of PD with systemic inflammation. Using the National Health and Nutrition Examination Survey 2009–2010, 2011–2012 and 2013–2014, participants who received periodontal exam and provided dietary recall data were included. The inflammatory potential of diet was calculated via DII. PD was defined according to the 2012 case definition. White blood cells (WBC), segmented neutrophils and C-reactive protein (CRP) were used as proxies for systemic inflammation. The periodontal measures were regressed across DII values using adjusted multivariate linear regression and adjusted mediation analysis. Overall, 10,178 participants were included. DII was significantly correlated with mean periodontal probing depth (PPD), mean clinical attachment loss (CAL), thresholds of PPD and CAL, WBC, segmented neutrophils and DII (p < 0.01). A linear regression logistic adjusted for multiple confounding variables confirmed the association between DII and mean PPD (B = 0.02, Standard Error [SE]: 0.02, p < 0.001) and CAL (B = −0.02, SE: 0.01, p < 0.001). The association of mean PPD and mean CAL with both WBC and segmented neutrophils were mediated by DII (from 2.1 to 3.5%, p < 0.001). In the 2009–2010 subset, the association of mean CAL with serum CRP was mediated by DII (52.0%, p < 0.01). Inflammatory diet and PD may be associated. Also, the inflammatory diet significantly mediated the association of leukocyte counts and systemic inflammation with PD.

The Influence of Diet on Oxidative Stress and Inflammation Induced by Bacterial Biofilms in the Human Oral Cavity

The article is a concise compendium of knowledge on the etiology of pathogenic microorganisms of all complexes causing oral diseases. The influence of particular components of the diet and the role of oxidative stress in periodontal diseases were described. The study investigated the bacteriostatic effect of the diet of adults in in vivo and in vitro tests on the formation of bacterial biofilms living in the subgingival plaque, causing diseases called periodontitis. If left untreated, periodontitis can damage the gums and alveolar bones. Anaerobic bacteria, called periopathogens or periodontopathogens, play a key role in the etiopathogenesis of periodontitis. The most important periopathogens of the oral microbiota are bacteria of all complexes, including the red complex. The obtained results suggest the possibility of using a specific diet in the prevention and treatment of periodontal diseases-already treated as a disease of civilization. The quoted article is an innovative compilation of knowledge on this subject and it can be a valuable source of knowledge for professional hygienists, dentists, peridontologists, dentistry students and anyone who cares about proper oral hygiene. The obtained results suggest the possibility of using this type of diet in the prophylaxis of the oral cavity in order to avoid periodontitis.

Exploring the relationship among dental caries, nutritional habits, and peri-implantitis

BACKGROUND

A study was made of the prevalence, co-occurrence and association among caries, nutritional habits, and peri-implant disease, with an analysis of the influence of other patient and implant factors upon peri-implant disease.

METHODS

The included subjects underwent a clinical examination and were asked to complete a questionnaire. Demographic data and potential lifestyle/behavioral variables were collected. Clinical and radiographic assessment allowed calculation of the decayed, missing and filled teeth (DMFT) index and peri-implant diagnosis. Uni- and multivariate multinomial logistic regression analyses were applied to identify predictors of peri-implant disease.

RESULTS

A total of 169 patients with 311 implants were studied. At patient level, 92.2% of the subjects presented at least one carious lesion, whereas 22.5% and 56.2% were diagnosed with peri-implantitis and mucositis, respectively. Those patients with more than two caries had a higher risk of mucositis (OR = 3.33). Statistically significant associations for peri-implantitis included full mouth periodontal indexes, sugar-rich diets, keratinized mucosa width, number of missing teeth and interproximal untreated caries or fillings adjacent to implants.

CONCLUSION

High caries risk profiles and mucositis/peri-implantitis tended to accumulate within subjects. A sugar-enriched diet and untreated caries or fillings adjacent to implant sites may be further considered as risk indicators of peri-implantitis.

Bleeding tendency and ascorbic acid requirements: systematic review and meta-analysis of clinical trials

CONTEXT

The World Health Organization set the recommended daily vitamin C intake, henceforth referred to as ascorbic acid (AA), on the basis of scurvy prevention. Double-blind AA depletion-repletion studies suggest that this recommended AA dose may be too low to prevent microvascular fragility.

OBJECTIVES

(1) To conduct a systematic review and meta-analysis of controlled clinical trials on whether AA supplementation leads to a reduced gingival bleeding tendency, a manifestation of microvascular fragility; and (2) to relate AA plasma levels to retinal hemorrhaging, another manifestation of microvascular fragility.

DATA SOURCES

Data were reviewed from 15 trials conducted in 6 countries with 1140 predominantly healthy participants with measures of gingival bleeding tendency, and from the National Health and Nutrition Examination Survey (NHANES) III of 8210 US residents with measures of retinal hemorrhaging.

RESULTS

In clinical trials, AA supplementation reduced gingival bleeding tendency when estimated baseline AA plasma levels were < 28 μmol/L (standardized mean difference [SMD], -0.83; 95%CI, -1.16 to -0.49; P < 0.002). Supplementation with AA did not unequivocally reduce gingival bleeding tendency when baseline estimated AA plasma levels were >48  μmol/L or unknown (respective standardized mean differences: -0.23, 95%CI, -0.45 to -0.01, P < 0.05; and -0.56; 95%CI: -1.19 to 0.06, P < 0.08). In NHANES III, prevalence of both retinal hemorrhaging and gingival bleeding tendency increased when AA plasma levels were within the range that protects against scurvy (11-28 μmol/L; respective prevalence ratios adjusted for age and sex: 1.47; 95%CI: 1.22-1.77; and 1.64; 95%CI: 1.32-2.03; P < 0.001 for both).

CONCLUSION

Consistent evidence from controlled clinical trials indicates that setting human AA requirements based on scurvy prevention leads to AA plasma levels that may be too low to prevent an increased gingival bleeding tendency. Gingival bleeding tendency and retinal hemorrhaging coincide with low AA plasma levels and thus may be reflective of a systemic microvascular pathology that is reversible with an increased daily AA intake.

A 12-month randomized controlled trial evaluating erythritol air-polishing versus curette/ultrasonic debridement of mandibular furcations in supportive periodontal therapy

Background

Due to complex morphology and limited access, the cleaning of the furcation area is extremely challenging. Therefore, novel therapeutic approaches need to be tested to potentially overcome debridement limitations. The aim of the present prospective 12-month study was to compare clinical and microbiological effects following erythritol air-polishing versus conventional mechanical debridement of furcation defects in a cohort of periodontal maintenance patients.

Methods

Twenty patients with grade II mandibular molar furcation defects volunteered to enroll in this single-centre, examiner masked, randomized controlled trial. In a split-mouth study design, two furcation sites in each patient were randomly assigned to either receive subgingival debridement using erythritol air-polishing (test) or conventional ultrasonic/curette debridement (control) at baseline, and at 3, 6, 9 and 12 months. Probing depth, clinical attachment level and bleeding on probing were recorded at 3-month intervals. Subgingival microbiological samples obtained at baseline, 6 and 12 months were analyzed using checkerboard DNA–DNA hybridization. Discomfort from treatment was scored at 12 months using a visual analogue scale. The differences between treatments, and time-points, were tested using multilevel analysis (mixed effect models and robust variance estimates).

Results

A significant reduction in probing depth took place following both treatments (p < 0.001). Control sites experienced a significant mean gain in clinical attachment level of 0.5 mm (± 0.2) (p = 0.004), whereas a non-significant gain of 0.4 mm (± 0.3) was observed at test sites (p = 0.119). At 6 months, a significant between-treatment difference of 0.8 mm (± 0.4) was observed in favor of the control (p = 0.032). No significant between-treatment differences were observed in microbial load or composition. Notably, at 12 months patients experienced significantly less discomfort following air-polishing compared with control (p = 0.001).

Conclusions

The 12-month observations indicate that erythritol air-polishing and conventional mechanical debridement both support clinical improvements. A significant between-treatment difference in clinical attachment level was, however, detected in favour of control debridement at 6 months. In terms of patient comfort, erythritol air-polishing is superior.

Trial Registration: The clinical trial was retrospectively registered in ClinicalTrial.gov with registration NCT04493398 (07/28/2020).

Annual review of selected scientific literature: A report of the Committee on Scientific Investigation of the American Academy of Restorative Dentistry

This comprehensive review of the 2019 restorative dental literature is offered to inform busy dentists regarding remarkable publications and noteworthy progress made in the profession. Developed by the Scientific Investigation Committee of the American Academy of Restorative Dentistry, each author brings discipline-specific expertise to 1 of 8 sections of the report: (1) prosthodontics; (2) periodontics, alveolar bone, and peri-implant tissues; (3) implant dentistry; (4) dental materials and therapeutics; (5) occlusion and temporomandibular disorders; (6) sleep-related breathing disorders; (7) oral medicine and oral and maxillofacial surgery; and (8) dental caries and cariology. The report targets important information likely to influence day-to-day dental treatment decisions. Each review is not intended to stand alone but to update interested readers so that they may visit source material when greater detail is desired. As the profession moves toward evidence-based clinical decision-making, an incredible volume of potentially valuable dental literature continues to increase. It is the intention of this review and its authors to provide assistance in negotiating the extensive dental literature published in 2019. It is our hope that readers find this work useful in the clinical management of dental patients.

Analysing the Relationship between Nutrition and the Microbial Composition of the Oral Biofilm-Insights from the Analysis of Individual Variability

The influence of a change in nutrition on the oral microbiota are discussed in literature, but usually only changes of population mean values are reported. This paper introduces simple methods to also analyse and report the variability of patients’ reactions considering data from the culture analysis of oral biofilm. The framework was illustrated by an experimental study exposing eleven participants to different nutrition schemes in five consecutive phases. Substantial inter-individual variations in the individual reactions were observed. A new coherence index made it possible to identify 14 instances where the direction of individual changes tended to coincide with the direction of the mean change with more than 95% probability. The heterogeneity in variability across different bacteria species was limited. This allowed us to develop recommendations for sample sizes in future studies. For studies measuring the concentration change of bacteria as a reaction to nutrition change, the use of replications and analysis of the variability is recommended. In order to detect moderate effects of a change in nutrition on the concentration of single bacterial taxa, 30 participants with three repetitions are often adequate. Insights into the relationship between nutrition and the microbial composition can be helpful for the development of dietary habits that promote the establishment of a healthy microbial flora and can therefore prevent the initiation of oral diseases such as caries and periodontitis.

Prevalence and severity of periodontal disease in a historical Austrian population

Objective

To assess the prevalence and severity of periodontitis based on different diagnostic methods in a historical Austrian population from the early middle ages.

Background

The description of the oral health status of archaeological material can provide interesting insights into prevalence, severity, and extent of oral diseases. Herein, the periodontal health status of the skeletal remains of medieval Avars (700‐800 AD), which were considered as one of the earliest Avarian settlements in Austria, was investigated.

Methods

The skeletal remains of 128 Avars were examined; age and gender were estimated by standard forensic methods and tooth loss and root caries were recorded. Periodontitis was assessed by (a) measurement of the alveolar bone levels (ABL) and (b) evaluation of the interdental septa.

Results

A mean ABL of 4.8 mm was determined, root caries tended to accumulate in teeth with a higher alveolar bone loss, and on average, 6.2 teeth were lost antemortem. Independent of the diagnostic method >90% of the subjects were judged as periodontally diseased, and age and tooth type were significant predictors. However, on the tooth level the presence of periodontitis varied considerably depending on the diagnostic method; that is, 7.6% versus 47.2% of the teeth were judged as healthy based on ABL or interdental septa, respectively.

Conclusion

The periodontal status of the skeletal remains of medieval Avars revealed a considerable high prevalence of periodontitis (ie, >90% of this population displayed periodontal tissue breakdown). However, the diagnostic method, disease definition, and data presentation should be considered when comparing results of archaeological material.

Effects of Short-Chain Fatty Acids on Human Oral Epithelial Cells and the Potential Impact on Periodontal Disease: A Systematic Review of In Vitro Studies

Short-chain fatty acids (SCFA), bacterial metabolites released from dental biofilm, are supposed to target the oral epithelium. There is, however, no consensus on how SCFA affect the oral epithelial cells. The objective of the present study was to systematically review the available in vitro evidence of the impact of SCFA on human oral epithelial cells in the context of periodontal disease. A comprehensive electronic search using five databases along with a grey literature search was performed. In vitro studies that evaluated the effects of SCFA on human oral epithelial cells were eligible for inclusion. Risk of bias was assessed by the University of Bristol's tool for assessing risk of bias in cell culture studies. Certainty in cumulative evidence was evaluated using GRADE criteria (grading of recommendations assessment, development, and evaluation). Of 3591 records identified, 10 were eligible for inclusion. A meta-analysis was not possible due to the heterogeneity between the studies. The risk of bias across the studies was considered "serious" due to the presence of methodological biases. Despite these limitations, this review showed that SCFA negatively affect the viability of oral epithelial cells by activating a series of cellular events that includes apoptosis, autophagy, and pyroptosis. SCFA impair the integrity and presumably the transmigration of leucocytes through the epithelial layer by changing junctional and adhesion protein expression, respectively. SCFA also affect the expression of chemokines and cytokines in oral epithelial cells. Future research needs to identify the underlying signaling cascades and to translate the in vitro findings into preclinical models.

What is the impact of the adjunctive use of omega-3 fatty acids in the treatment of periodontitis? A systematic review and meta-analysis

Background

Host modulation therapy has gained increasing interest in periodontal therapy. This systematic review aimed to evaluate the effects of adjunctive administration of omega-3 fatty acids in periodontal therapy.

Methods

The search strategy was determined using the “patient, intervention, comparison, outcome” model. A resulting search term was generated using keywords, and the databases were fed. The databases PubMed, Cochrane Library, and LIVIVO were used. Studies were selected for the literature review based on previously specified inclusion and exclusion criteria. Randomized, controlled, blinded studies, longitudinal studies, comparative studies, and clinical studies were included in the review. Additionally, they used omega-3 fatty acids in the treatment of periodontitis. The following parameters were observed: clinical attachment level (CAL), probing depth (PD), gingival index (GI), bleeding on probing (BOP) and plaque index (PI). A meta-analysis was performed for PD and CAL after 3 months. By analyzing the risk of bias, the validity of the results of each study was demonstrated, and its credibility and quality were assessed.

Results

Of 14 studies found, six were included. The results showed a significant reduction in PD and CAL compared to that in the placebo groups in four out of six involved studies, which was confirmed by the meta-analysis. In one study, a significant reduction in BOP was found. GI was significantly reduced in three included studies. PI also showed a significant reduction in three studies.

Conclusions

Within the study limitations, omega-3 fatty acids appear to have a positive effect on periodontal wound healing with regard to reduction in CAL and PD. Based on the results, patients receiving periodontal treatment might benefit from nutritional counseling.

Could Vitamin D influence risk for Periodontal Disease - to "D" or not to "D"?

PURPOSE OF REVIEW

The purpose of this review is to discuss the literature on associations between vitamin D and periodontal disease, including its strengths and weaknesses. Future direction for continued work in this area is provided.

RECENT FINDINGS

Research in cross-sectional cohorts, surveys, and case-control studies provide support for a role of vitamin D in periodontal disease, especially using clinical indicators such as bleeding on probing and clinical attachment loss. However, these studies have a number of limitations. They cannot establish temporality of these associations. Most case-control studies have been limited in sample size and have inconsistent findings. A number of cross-sectional studies are restricted to select populations (e.g., persons with HIV, diabetes, rheumatoid arthritis) limiting extrapolation of findings to the general aging population.Fewer prospective studies have been conducted, and only three have examined associations using a biomarker for vitamin D that reflects exposure from all its sources (sunlight, diet and supplements). One study is limited by using self-reported measures of disease outcomes, and only two used measures of alveolar crestal height. However, of the prospective studies published, there is a suggestion that vitamin D might prevent against tooth loss. Only two randomized controlled trials have examined these associations, and they support the effects of vitamin D supplementation on prevention of tooth loss and gingival bleeding.

SUMMARY

We strongly suggest that new research should focus on prospective study designs with followup of participants longer than a decade and long-term clinical trials. Such studies should incorporate measures of alveolar bone loss and tooth loss with indication for reason for tooth loss. Such clinical trials should be designed to examine both the influence of vitamin D supplementation alone as well as with other nutrients (e.g., calcium) or therapeutic medications (e.g., bisphosphonates). Currently, there is no strong evidence to suggest that vitamin D protects against development of periodontal disease.

Butyrate Decreases ICAM-1 Expression in Human Oral Squamous Cell Carcinoma Cells

Short-chain fatty acids (SCFA) are bacterial metabolites that can be found in periodontal pockets. The expression of adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1) within the epithelium pocket is considered to be a key event for the selective transmigration of leucocytes towards the gingival sulcus. However, the impact of SCFA on ICAM-1 expression by oral epithelial cells remains unclear. We therefore exposed the oral squamous carcinoma cell line HSC-2, primary oral epithelial cells and human gingival fibroblasts to SCFA, namely acetate, propionate and butyrate, and stimulated with known inducers of ICAM-1 such as interleukin-1-beta (IL1β) and tumor necrosis factor-alfa (TNFα). We report here that butyrate but not acetate or propionate significantly suppressed the cytokine-induced ICAM-1 expression in HSC-2 epithelial cells and primary epithelial cells. The G-protein coupled receptor-43 (GPR43/ FFAR2) agonist but not the histone deacetylase inhibitor, trichostatin A, mimicked the butyrate effects. Butyrate also attenuated the nuclear translocation of p65 into the nucleus on HSC-2 cells. The decrease of ICAM-1 was independent of Nrf2/HO-1 signaling and phosphorylation of JNK and p38. Nevertheless, butyrate could not reverse an ongoing cytokine-induced ICAM-1 expression in HSC-2 cells. Overall, these observations suggest that butyrate can attenuate cytokine-induced ICAM-1 expression in cells with epithelial origin.

Integrated hypothesis of dental caries and periodontal diseases

This review considers an integrated hypothesis of dental caries and periodontal diseases that builds on theoretical ecological principles. The backbone of the hypothesis is based on the dynamic stability stage of the oral microbiota, at which intrinsic (mainly saliva and gingival crevicular fluid) and bacterial (mainly metabolic) resilience factors maintain ecological dynamic stability, compatible with clinical health. However, loss of intrinsic resilience factors and/or prolonged changes in the availability of microbial metabolic substrates may shift the ecological balance of the microbiota into either saccharolytic (acidogenic) or amino acid-degrading/proteolytic (alkalinogenic) stages, depending on the nature of the predominant substrates, leading to clinical diseases. Therefore, to maintain and restore the dynamic stability of the oral microbiota, it is necessary to control the drivers of disease, such as salivary flow and influx of bacterial nutrients into the oral cavity. Contrary to conventional wisdom, excessive intake of fermentable carbohydrates may contribute to inflammation in periodontal tissues resulting from hyperglycaemia. An integrated hypothesis emphasizes that both dental caries and periodontal diseases originate in the dynamic stability stage and emerge in response to nutritional imbalances in the microbiota. Periodontal diseases may belong to the sugar driven inflammatory diseases, similar to diabetes, obesity, and cardiovascular diseases.

Effectiveness of vitamin D for adult patients with gingivitis

BACKGROUND

This study aims to explore the effectiveness of vitamin D for the management of adult patients with gingivitis.

METHODS

We will perform a comprehensive search from the following electronic databases: Cochrane Library, PUBMED, EMBASE, AMED, CINAHL, WANGFANG, VIP, CBM, and China National Knowledge Infrastructure. All databases will be searched from their inceptions to the present without language limitation. We will also search for unpublished data to avoid missing more potential studies. Two authors will carry out study selection, data extraction, and methodological quality evaluation, respectively. RevMan 5.3 software will be utilized for statistical analysis.

RESULTS

This study will summarize the up-to-date evidence about the anti-inflammatory effect of vitamin D for the management of adult patients with gingivitis through assessing modified gingival, gingival bleeding indices, inflammatory factors, plaque, quality of life, and any adverse events.

CONCLUSION

This study may provide helpful evidence of vitamin D for the management of adult patients with gingivitis for clinical practice.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42019156561.