Personalized periodontal treatment for the tobacco- and alcohol-using patient

Assessment of the Effect on Periodontitis of Antibiotic Therapy and Bacterial Lysate Treatment

Periodontitis is an inflammatory process that starts with soft tissue inflammation caused by the intervention of oral bacteria. By modulating local immunity, it is possible to supplement or replace current therapeutic methods. The aim of this study was to compare the effects of an immunostimulatory treatment with the antibiotherapy usually applied to periodontitis patients. On a model of periodontitis induced in 30 rats (divided into three equal groups) with bacterial strains selected from the human oral microbiome (Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum and Streptococcus oralis), we administered antibiotics, bacterial lysates and saline for 10 days. Clinically, no significant lesions were observed between the groups, but hematologically, we detected a decrease in lymphocyte and neutrophil counts in both the antibiotic and lysate-treated groups. Immunologically, IL-6 remained elevated compared to the saline group, denoting the body's effort to compensate for bone loss due to bacterial action. Histopathologically, the results show more pronounced oral tissue regeneration in the antibiotic group and a reduced inflammatory reaction in the lysate group. We can conclude that the proposed bacterial lysate has similar effects to antibiotic therapy and can be considered an option in treating periodontitis, thus eliminating the unnecessary use of antibiotics.

CXCL8, MMP12, and MMP13 are common biomarkers of periodontitis and oral squamous cell carcinoma

OBJECTIVE

To analysis the relationship between periodontitis (PD) and oral squamous cell carcinoma (OSCC) by bioinformatic analysis.

MATERIALS AND METHODS

We analyzed the gene expression profiles of PD (GSE16134) from the Gene Expression Omnibus (GEO) database and OSCC samples from TCGA-HNSC (head and neck squamous cell carcinoma) and identified common differentially expressed genes (DEGs) in PD and OSCC. Then, functional annotation and signaling pathway enrichment, protein interaction network construction, and hub gene identification were performed. Subsequently, the function and signaling pathway enrichment of hub genes, miRNA interaction, and transcription factor interaction analyses were carried out. We analyzed GSE10334 and GSE30784 as validation datasets, and performed qRT-PCR experiments simultaneously for validation, and obtained 4 hub genes. Finally, immune infiltration analysis and clinical correlation analysis of 4 hub genes and related miRNAs were performed.

RESULTS

We identified 31 DEGs (16 up-regulated and 15 down-regulated). Four hub genes were obtained by qRT-PCR and validation dataset analysis, including IL-1β, CXCL8, MMP12, and MMP13. The expression levels of them were all significantly upregulated in both diseases. The functions of these genes focus on three areas: neutrophil chemotaxis, migration, and CXCR chemokine receptor binding. Key pathways include IL-17 signaling pathway, chemokine signaling pathway, and cytokine-cytokine receptor interactions pathway. Immune infiltration analysis showed that the expressions of 4 hub genes were closely related to a variety of immune cells. ROC curve analysis indicated that AUCs of 4 hub genes are all greater than 0.7, among which MMP12 and MMP13 were greater than 0.9. Kaplan-Meier survival analysis indicated that worse OS was strongly correlated with CXCL8 and MMP13 high-expression groups. MMP12 low-expression group was strongly associated with worse OS. The results of multivariate Cox regression analysis showed that age, N stage, CXCL8, MMP12, and MMP13 were independent prognostic factors for OS. We also identified 3 miRNAs, including hsa-miR-19b-3p, hsa-miR-181b-2-3p, and hsa-miR-495-3p, that were closely related to 4 hub genes. Hsa-miR-495-3p is closely related to the diagnosis and prognosis of OSCC.

CONCLUSIONS

We identified 4 hub genes between PD and OSCC, including IL-1β, CXCL8, MMP12, and MMP13. These genes may mediate the co-morbid process of PD and OSCC through inflammation-related pathways such as the IL-17 signaling pathway. It is worth noting that CXCL8, MMP12, and MMP13 have great significance in the diagnosis and prognosis of OSCC.

Tobacco-enhanced biofilm formation by Porphyromonas gingivalis and other oral microbes

Microbial biofilms promote pathogenesis by disguising antigens, facilitating immune evasion, providing protection against antibiotics and other antimicrobials and, generally, fostering survival and persistence. Environmental fluxes are known to influence biofilm formation and composition, with recent data suggesting that tobacco and tobacco-derived stimuli are particularly important mediators of biofilm initiation and development in vitro and determinants of polymicrobial communities in vivo. The evidence for tobacco-augmented biofilm formation by oral bacteria, tobacco-induced oral dysbiosis, tobacco-resistance strategies, and bacterial physiology is summarized herein. A general overview is provided alongside specific insights gained through studies of the model and archetypal, anaerobic, Gram-negative oral pathobiont, Porphyromonas gingivalis.

Factors Associated with the Extent of Clinical Attachment Loss in Periodontitis: A Multicenter Cross-Sectional Study

Periodontitis has significant public health implications, affecting individuals' overall health, well-being, and quality of life. This study aimed to assess the risk factors associated with the extent of clinical attachment loss (CAL) in a population diagnosed with periodontitis. Six hundred and sixty-seven patients with different degrees of CAL (mild, n = 223; moderate, n = 256; and advanced, n = 188) were enrolled. Socio-demographics, lifestyle, microbiological profiles, specific immune response, obesity, and single-nucleotide polymorphism of the IL1 gene were determined. Unconditional logistic regression models were conducted to determine the factors associated with the extent of CAL. Aging, smoking, microbial factors, plaque index, and IgG2 antibodies against Aggregatibacter actinomycetemcomitans were associated with advanced CAL. IgG2 antibodies against A. actinomycetemcomitans (OR 1.50; CI 95% 1.23-1.81), plaque accumulation (OR 2.69; CI 95% 2.20-3.29), Porphyromonas gingivalis (OR 1.93; CI 95% 1.35-2.76), Tanerella forsythia (OR 1.88; CI 95%1.30-2.70), and current smoking (OR 1.94; CI 95% 1.31-2.87) were associated with advanced CAL. Gene IL polymorphisms, obesity, and stress were not associated with the extent of CAL. Aging, plaque accumulation, smoking, and having antibodies against A. actinomycetemcomitans were the most critical factors associated with advanced CAL. In contrast, obesity, stress, and gene polymorphisms were not associated with the extent of CAL.

Healthy lifestyles are associated with a better response to periodontal therapy: A prospective cohort study

AIM

To evaluate the association between lifestyle behaviours and clinical periodontal outcomes following Steps 1/2 of periodontal therapy.

METHODS

A total of 120 subjects with untreated Stage II/III periodontitis participated in this study. At baseline, questionnaires were administered to assess the following lifestyle behaviours: adherence to Mediterranean diet (MD), physical activity (PA) and stress levels, sleep quality, smoking and alcohol use. Participants received Steps 1/2 of periodontal therapy and were re-evaluated after 3 months. A composite outcome of the endpoint of therapy (i.e., no sites with probing pocket depth [PPD] ≥4 mm with bleeding on probing, and no sites with PPD ≥ 6 mm) was regarded as the primary outcome. Simple and multiple regression analyses were used to evaluate the association between lifestyle behaviours and clinical periodontal outcomes. Disease severity at baseline, body mass index, diabetes, household disposable income and plaque control were considered as confounders.

RESULTS

Multiple regression analyses showed significantly lower odds of achieving the endpoint of therapy in subjects with poor sleep quality (odds ratio [OR] = 0.13; 95% confidence interval [CI]: 0.03-0.47; p < .01), smoking (OR = 0.18; 95% CI: 0.06-0.52; p < .05) and alcohol use above the suggested intake (OR = 0.21; 95% CI: 0.07-0.63; p < .01). Subjects with a combination of 'unhealthy lifestyles' (low adherence to MD and low PA levels and high levels of stress and poor sleep quality) showed higher proportions of residual PPD≥6 mm (MD = 1.51; 95% CI: 0.23-2.80; p < .05) and lower odds of achieving the endpoint of therapy (OR = 0.85; 95% CI: 0.33-0.99; p < .05) at re-evaluation.

CONCLUSIONS

Subjects with unhealthy lifestyle behaviours showed worse clinical outcomes 3 months after Steps 1/2 of periodontal therapy.

Tau-Marin Mucoadhesive Gel for Prevention and Treatment of Gum Diseases

An innovative and stable probiotic-containing mucoadhesive gel (AL0020), integrated with botanical extracts, has been developed to rebalance the dysbiosis associated with periodontal diseases. Tau-Marin gel, prepared with anhydrous ingredients to prevent the replication of bacteria and ensure good stability over time, was tested against some pathogenic bacteria, belonging to the so-called "red complex", recognized as the most important pathogens in plaque specimens, adherent to the epithelial lining of periodontal pockets. This lipogel was tested in vitro, in a physiological solution (PS) and in a simulated saliva (SS), for up to 8 h, to monitor its ability to release probiotics over time. Probiotics were enumerated through two different techniques, Lacto-Counter Assay (LCA) and Colony Forming Unit (CFU). A detailed physico-chemical profile of AL0020 and its in vitro efficacy in protecting activity against pathogenic bacteria as well as soothing or irritative effect on gingival epithelium were reported. Moreover, a clinical-dermatological trial on 20 volunteers using the product once a day for 30 days was also performed, where the efficacy of the gel in the control of gum disorders was observed.

Role of Oral Health, Frailty, and Minimal Hepatic Encephalopathy in the Risk of Hospitalization: A Prospective Multi-Center Cohort of Outpatients With Cirrhosis

BACKGROUND & AIMS

Hospitalizations are a sentinel event in cirrhosis; however, the changing demographics in patients with cirrhosis require updated hospitalization prediction models. Periodontitis is a risk factor for liver disease and potentially progression. The aim of this study was to determine factors, including poor oral health, associated with 3-month hospitalizations in a multi-center cohort of outpatients with cirrhosis.

METHODS

North American Consortium for Study of End-stage Liver Disease (NACSELD-3), a new study cohort, recruits outpatients with cirrhosis. Cirrhosis details, demographics, minimal hepatic encephalopathy (MHE), frailty, and comorbid conditions including oral health were collected. All patients were followed for 3 months for nonelective hospitalizations. Multi-variable models were created for this outcome using demographics, cirrhosis details, oral health, MHE, frailty, and comorbid conditions with K-fold internal validation using 25%/75% split.

RESULTS

A total of 442 outpatients (70% men; 37% compensated; Model for End-stage Liver Disease-Sodium, 12; 42% ascites; and 33% prior HE) were included. MHE was found in 70%, frailty in 10%; and both in 8%. In terms of oral health, 15% were edentulous and 10% had prior periodontitis. Regarding 3-month hospitalizations, 14% were admitted for mostly liver-related reasons. These patients were more likely to be decompensated with higher cirrhosis complications, MHE, frailty and periodontitis history. Multi-variable analysis showed prior periodontitis (P = .026), composite MHE + frailty score (P = .0016), ascites (P = .004), prior HE (P = .008), and hydrothorax (P = .004) were associated with admissions using the training and validation subsets.

CONCLUSIONS

In a contemporaneous, prospective, multi-center cohort study in outpatients with cirrhosis, poor oral health is significantly associated with 3-month hospitalizations independent of portal hypertensive complications, MHE, and frailty. Potential strategies to reduce hospitalizations should consider oral evaluation in addition to MHE and frailty assessment in practice pathways.

Benefits of Antimicrobial Photodynamic Therapy as an Adjunct to Non-Surgical Periodontal Treatment in Smokers with Periodontitis: A Systematic Review and Meta-Analysis

The objective of this study was to analyze evidence of the clinical and microbiological benefits of antimicrobial photodynamic therapy (aPDT) adjunctive to scaling and root planing (SRP) in smokers with periodontitis. Randomized clinical trials (RCTs) were included, through an electronic search in PubMed/MEDLINE, LILACS, Web of Science, and the Cochrane Library for articles published in English until December 2022. The quality of the studies was assessed using the JADAD scale and the risk of bias was estimated using the Cochrane Collaboration assessment tool. Of the 175 relevant articles, eight RCTs were included. Of these, seven reported clinical results and five microbiological results, with a follow-up time of 3–6 months. A meta-analysis was performed for the probing depth (PD) reduction and clinical attachment level (CAL) gain at 3 and 6 months. The weighted mean differences (WMDs) and 95% confidence intervals (CIs) were counted for the PD and CAL. The overall effect for the PD reduction at 3 and 6 months (WMD = −0.80, 95% CI = −1.44 to −0.17, p = 0.01; WMD = −1.35, 95% CI = −2.23 to −0.46, p = 0.003) was in favor of aPDT. The CAL gain (WMD = 0.79, 95% CI = −1.24 to −0.35, p = 0.0005) was statistically significant at 6 months, in favor of aPDT. In these RCTs, aPDT was unable to demonstrate efficacy in reducing the microbial species associated with periodontitis. aPDT as an adjuvant to SRP improves the PD reduction and CAL gain more effectively than only SRP. RCTs are needed to establish standardized protocols with longer follow-up times in order to provide more results on aPDT adjunctive to SRP in smokers with periodontitis.

Drinking motives as a predictor of readiness to change alcohol use

Drinking motives have been identified as important predictors of alcohol consumption. Similarly, the degree of readiness to change (RTC) can predict behavioral changes when drinking alcohol. However, the link between drinking motives and RTC has not been explored in previous research. The aim of this study is to investigate whether the four drinking motives (coping, enhancement, social, conformity) can predict the three stages of RTC (precontemplation, contemplation and action) in relation to alcohol consumption. Two hundred and fifty-two undergraduates’ students completed an online self-assessment survey on Qualtrics that assessed motives for alcohol use, drinking behavior, and RTC. Hierarchical regressions showed that among the four specific drinking motives, coping motives significantly predicted all three stages of RTC; conformity motives positively predicted the action stage of change; social motives negatively predicted the precontemplation and action stages of change; enhancement motives were not significant in predicting RTC stages. These results indicate that the three RTC levels can be predicted by coping, social, and conformity motives, but not by enhancement motives. Additionally, given the importance of coping motives, it might be useful to address and include healthier coping mechanisms as part of clinical interventions and prevention methods to circumvent unsafe drinking behaviors independent of a single RTC stage.

Genome- and Transcriptome-Wide Association Studies Identify Susceptibility Genes and Pathways for Periodontitis

Several genes associated with periodontitis have been identified through genome-wide association studies (GWAS); however, known genes only explain a minority of the estimated heritability. We aimed to explore more susceptibility genes and the underlying mechanisms of periodontitis. Firstly, a genome-wide meta-analysis of 38,532 patients and 316,185 healthy controls was performed. Then, cross- and single-tissue transcriptome-wide association studies (TWAS) were conducted based on GWAS summary statistics and the Genotype-Tissue Expression (GTEx) project. Risk genes were evaluated to determine if they were differentially expressed in periodontitis sites compared with unaffected sites using public datasets. Finally, gene co-expression network analysis was conducted to identify the functional biology of the susceptible genes. A total of eight single nucleotide polymorphisms (SNPs) within the introns of lncRNA LINC02141 approached genome-wide significance after meta-analysis. EZH1 was identified as a novel susceptibility gene for periodontitis by TWAS and was significantly upregulated in periodontitis-affected gingival tissues. EZH1 co-expression genes were greatly enriched in the cell-substrate junction, focal adhesion and other important pathways. Our findings may offer a fundamental clue for comprehending the genetic mechanisms of periodontitis.

Impact of the host response and osteoblast lineage cells on periodontal disease

Periodontitis involves the loss of connective tissue attachment and alveolar bone. Single cell RNA-seq experiments have provided new insight into how resident cells and infiltrating immune cells function in response to bacterial challenge in periodontal tissues. Periodontal disease is induced by a combined innate and adaptive immune response to bacterial dysbiosis that is initiated by resident cells including epithelial cells and fibroblasts, which recruit immune cells. Chemokines and cytokines stimulate recruitment of osteoclast precursors and osteoclastogenesis in response to TNF, IL-1β, IL-6, IL-17, RANKL and other factors. Inflammation also suppresses coupled bone formation to limit repair of osteolytic lesions. Bone lining cells, osteocytes and periodontal ligament cells play a key role in both processes. The periodontal ligament contains cells that exhibit similarities to tendon cells, osteoblast-lineage cells and mesenchymal stem cells. Bone lining cells consisting of mesenchymal stem cells, osteoprogenitors and osteoblasts are influenced by osteocytes and stimulate formation of osteoclast precursors through MCSF and RANKL, which directly induce osteoclastogenesis. Following bone resorption, factors are released from resorbed bone matrix and by osteoclasts and osteal macrophages that recruit osteoblast precursors to the resorbed bone surface. Osteoblast differentiation and coupled bone formation are regulated by multiple signaling pathways including Wnt, Notch, FGF, IGF-1, BMP, and Hedgehog pathways. Diabetes, cigarette smoking and aging enhance the pathologic processes to increase bone resorption and inhibit coupled bone formation to accelerate bone loss. Other bone pathologies such as rheumatoid arthritis, post-menopausal osteoporosis and bone unloading/disuse also affect osteoblast lineage cells and participate in formation of osteolytic lesions by promoting bone resorption and inhibiting coupled bone formation. Thus, periodontitis involves the activation of an inflammatory response that involves a large number of cells to stimulate bone resorption and limit osseous repair processes.

The role of cigarette smoking in periodontal disease and treatment outcomes of dental implant therapy

Tobacco smoking has been implicated in periodontal pathology through various mechanisms, including perturbations of the inflammatory and host responses to putative periodontal pathogens, alterations in the subgingival microbial communities, and a compromised healing potential of the tissues leading to imbalance of tissue homeostasis. This review provides the evidence for the relationship between cigarette smoking and periodontal disease in an attempt to explain possible mechanisms of how tobacco smoking may exert its negative effects on the periodontal tissues via systemic and localized pathways. Early and more recent studies explore cigarette smoking-induced changes in periodontal clinical indices; in subgingival microbial flora by employing traditional detection methods for selected microorganisms, in addition to modern techniques such as deep sequencing and bioinformatics analyses that are able to fully characterize the microbial communities; and in inflammatory and immune responses critically appraising study limitations and differences in study protocol designs. Periodontal treatment outcomes and implant therapy outcomes are reviewed in an attempt to shed light on possible mechanisms for the inferior treatment outcome noted in smokers. The potential harmful effects of passive smoking are also reviewed, providing evidence for the advantages of smoking cessation. Quitting cigarette smoking should be recommended by the dentist, and effort should be made to inform smokers about the negative effects of smoking on the periodontal status and implant therapy outcomes.

Association between coffee consumption and periodontal diseases: a systematic review and meta-analysis

BACKGROUND

Several studies have demonstrated association between coffee consumption and periodontal diseases. However, no systematic review and meta-analysis was performed. Therefore, we performed a systematic review and meta-analysis to evaluate the association between coffee intake and periodontitis.

METHODS

We defined PICO statement as "Do coffee drinkers have a higher association of periodontitis or tooth loss than non-coffee drinkers?". We searched for articles using the Embase and Medline databases. The odds ratio was used as an effect measure to evaluate the association between coffee and periodontitis We divided coffee intake doses into three groups: no intake (≤ 0.03 cups/day), low intake (0.03 < x < 1 cups/day), and high intake (≥ 1 cup/day). Cohort and cross-sectional studies were eligible for inclusion in this study. The Newcastle-Ottawa scale was used to qualitatively assess the risk of bias. The degree of heterogeneity between studies was quantified using I² statistics.

RESULTS

Six articles were analysed, including two cohort studies and four cross-sectional studies. The pooled unadjusted odds ratios of periodontitis were 1.14 (0.93-1.39), 1.05 (0.73-1.52), 1.03 (0.91-1.16) and 1.10 (0.84-1.45) in the 4 meta-analyses (coffee drinker vs. non-coffee drinker, high intake vs. low intake, low intake vs. no intake, high intake vs. no intake), respectively.

CONCLUSION

This is the first meta-analysis to investigate the relationship between coffee consumption and periodontitis. There was no relationship between coffee consumption and periodontitis. Further studies are required to assess whether a relationship between coffee consumption and periodontitis exists or not. PROSPERO registration number: CRD42022301341.

Clinical Oral Condition Analysis and the Influence of Highly Active Antiretroviral Therapy on Human Salivary Microbial Community Diversity in HIV-Infected/AIDS Patients

The purpose of this study was to assess the clinical oral status and investigate the effect of highly active antiretroviral therapy (HAART) on oral flora diversity in human immunodeficiency virus (HIV)-infected/acquired immune deficiency syndrome (AIDS) patients. We first recorded and analyzed the demographic indicators of 108 HIV-infected patients and assessed their periodontal health, dental health and oral lesion status by oral examination. Besides, we compared the changes in salivary microbial communities of healthy controls, before and after treatment of HAART-processed AIDS patients by Roche 454 sequencing and RT-qPCR. In HIV-infected/AIDS patients, age, sex, marital status, income level, smoking and oral health behaviors had an effect on periodontal clinical indicators; age and marital status were correlated with dental clinical indicators; most of them were accompanied by oral manifestations, mainly including candidiasis albicans, salivary gland disease, AIDS-associated periodontitis, and oral ulcers. Besides, a total of 487 species were detected in the saliva of AIDS patients. The microbial communities of HAART-unprocessed AIDS patients significantly differed from those processed patients, with 112 unique microbial species. More importantly, a large number of conditioned pathogens were also detected in the saliva samples of AIDS patients, which may be associated with opportunistic infections. Therefore, HAART might have a crucial role in salivary microecological balance in AIDS patients. And these patients should pay attention to the maintenance of oral health, and the early initiation of HAART may be important for the development of oral lesions.

Impact of smoking on peri-implant bleeding on probing

BACKGROUND

Studies around natural dentition demonstrated that smoking can reduce the tendency of inflamed tissue to bleed upon probing after controlling for possible confounders. In addition, previous research suggested that smokers may present alterations of the peri-implant microbiome.

AIM

This study aimed at investigating the impact of smoking on: (1) peri-implant bleeding on probing (BOP; primary objective); (2) the association between BOP/bone loss and BOP/visible gingival inflammation; (3) peri-implant microbiome.

METHODS

Partially edentulous patients with implants restored with a single crowns were included in this study. Subjects were either smokers (≥1 cigarettes per day) or nonsmokers (never smokers). The primary outcome of this cross-sectional study was BOP and secondary outcomes included: Probing pocket depth (PPD), Modified gingival Index (mGI) and Progressive Marginal Bone Loss. In addition, microbial profiles of the subjects were assessed through sequencing of the 16S rRNA gene. Univariate and multilevel multivariate analyses by means of Generalized Estimating Equations were conducted to analyze the association between smoking and peri-implant BOP.

RESULTS

Overall, 27 nonsmokers and 27 smokers were included and 96.3% and 77.78% of patients presented peri-implant BOP in the nonsmoker and smoker group, respectively (p = 0.046). Smoking was inversely associated with BOP in the multivariate multilevel analysis (OR = 0.356; 95% CI: 0.193-0.660; p = 0.001) whereas a positive correlation was demonstrated for mGI > 0 (OR = 3.289; 95% CI: 2.014-5.371; p < 0.001); PPD (OR = 1.692; 95% CI: 0.263-0.883; p = 0.039) and gender (OR = 2.323; 95% CI: 1.310-4.120 p = 0.004). A decrease of BOP sensitivity in detecting visible gingival inflammation (mGI > 0) was observed in smokers. Besides, taxonomic and changes in diversity regarding the peri-implant microbiota were detected comparing the two groups. Significantly higher richness of the microbiota was demonstrated in the smoker group when implants affected by peri-implantitis were compared to either healthy implants or implants presenting mucositis.

CONCLUSIONS

Smoking is a potential modifier of BOP and peri-implant microbiota.

Radiographic Bone Loss and Its Relation to Patient-Specific Risk Factors, LDL Cholesterol, and Vitamin D: A Cross-Sectional Study

The influence of patient-specific factors such as medical conditions, low-density lipoprotein cholesterol (LDL-C) or levels of 25-hydroxyvitamin D (25OHD) on periodontal diseases is frequently discussed in the literature. Therefore, the aim of this retrospective cross-sectional study was to evaluate potential associations between radiographic bone loss (RBL) and patient-specific risk factors, particularly LDL-C and 25OHD levels. Patients from a dental practice, who received full-mouth cone beam CTs (CBCTs) and blood-sampling in the course of implant treatment planning, were included in this study. RBL was determined at six sites per tooth from CBCT data. LDL-C and 25OHD levels were measured from venous blood samples. Other patient-specific risk factors were assessed based on anamnesis and dental charts. Statistical analysis was performed applying non-parametric procedures (Mann–Whitney U tests, error rates method). Data from 163 patients could be included in the analysis. RBL was significantly higher in male patients, older age groups, smokers, patients with high DMFT (decayed/missing/filled teeth) score, lower number of teeth, and high LDL-C levels (≥160 mg/dL). Furthermore, patients with high 25OHD levels (≥40 ng/mL) exhibited significantly less RBL. In summary, RBL was found to be associated with known patient-specific markers, particularly with age and high LDL-C levels.

Current Concepts in the Management of Periodontitis

Periodontitis is a common disorder affecting >40% of adults in the United States. Globally, the severe form of the disease has a prevalence of 11%. In advanced cases, periodontitis leads to tooth loss and reduced quality of life. The aetiology of periodontitis is multifactorial. Subgingival dental biofilm elicits a host inflammatory and immune response, ultimately leading to irreversible destruction of the periodontium (i.e. alveolar bone and periodontal ligament) in a susceptible host. In order to successfully manage periodontitis, dental professionals must understand the pathogenesis, primary aetiology, risk factors, contributing factors and treatment protocols. Careful diagnosis, elimination of the causes and reduction of modifiable risk factors are paramount for successful prevention and treatment of periodontitis. Initial non-surgical periodontal therapy primarily consists of home care review and scaling and root planing. For residual sites with active periodontitis at periodontal re-evaluation, a contemporary regenerative or traditional resective surgical therapy can be utilised. Thereafter, periodontal maintenance therapy at a regular interval and long-term follow-ups are also crucial to the success of the treatment and long-term retention of teeth. The aim of this review is to provide current concepts of diagnosis, prevention and treatment of periodontitis. Both clinical and biological rationales will be discussed.

Dysregulation of metallothionein and zinc aggravates periodontal diseases

BACKGROUND

Periodontitis (PD) is a multifaceted inflammatory disease connected to bacterial infection that results in the destruction of tooth supporting structures and eventually tooth loss. Given their involvement in infection and inflammation, both metallothionein (MT) and zinc (Zn) might play vital roles in the development and progression of PD. More specifically, both MT and Zn are heavily involved in regulating immune functions, controlling bacterial infection, balancing inflammatory responses, and reducing oxidative stress, all of which are associated with the pathogenesis of PD.

OBJECTIVE

This review paper will explore the physiological functions of MT and Zn and hypothesise how dysregulation could negatively affect periodontal health, leading to PD.

FINDINGS

Bacterial lipopolysaccharide (LPS) derived from periodontal pathogens, namely P. gingivalis initiates the acute phase response, thus upregulating the expression of MT which leads to the subsequent deficiency of Zn, a hallmark of periodontal disease. This deficiency leads to ineffective NETosis, increases the permeability of the gingival epithelium, and disrupts the humoral immune response, collectively contributing to PD. In addition, the presence of LPS in Zn deficient conditions favours M1 macrophage polarisation and maturation of dendritic cells, and also inhibits the anti-inflammatory activity of regulatory T cells. Collectively, these observations could theoretically give rise to the chronic inflammation seen in PD.

CONCLUSION

A disrupted MT and Zn homeostasis is expected to exert an adverse impact on periodontal health and contribute to the development and progression of PD.

Impact of Smoking Cessation on Periodontal Tissues

There is cumulative evidence supporting the negative effects of smoking on periodontal tissues. Smoking cessation can be successfully accomplished through specific programs, including behaviour modification and medications, and has been suggested as a suitable way to reduce the risk of several diseases, including periodontitis. The aim of this review is to provide a concise overview of the current knowledge about the impact of smoking cessation on periodontal tissues and therapy, with data from studies published in the last 15 years. Literature was searched using Medline database from 2005 up to and including September 2020 using medical subject heading (MeSH) terms and other search terms, restricted to the English language. Studies were evaluated and summarised in a narrative review format. Results demonstrated that there is convincing evidence to support the benefits of tobacco cessation in reducing the risk of periodontitis and tooth loss. In addition, the harmful effects of smoking on periodontal tissues seem to be assuaged as the number of years since quitting increases. The existing current evidence, even limited, also shows that smoking cessation may result in additional benefits to the outcome of nonsurgical periodontal treatment. Periodontal care providers should not only check their patient's smoking habit for estimating risk of disease progression and predictability of periodontal therapy, but they should also help smokers improve their oral and systemic health by providing efficient and personalised tobacco‐cessation counselling and treatment.

Photobiomodulation Therapy by 820 nm Diode Laser on Nonsurgical Periodontal Treatment of Smoker and Nonsmoker Patients: A Single-Blind Parallel Randomized Clinical Trial

The effect of smoking on nonsurgical periodontal treatment (SRP) is known, but the adjunct use of photobiomodulation (PBMT) to SRP has not been fully investigated in smokers. This study aimed to assess the effect of 820 nm diode laser on SRP in smoker/nonsmoker. Sixty patients (smokers/n = 30, nonsmokers/n = 30) were enrolled in this parallel-arm clinical study. All patients were divided into two main groups: SRP and PBMT + SRP. In PMBT + SRP groups, 7.96 J cm^-2 energy was applied by 820nm diode laser at baseline and first, second and third weeks after SRP. Periodontal pocket depth (PPD), gingival index (GI), plaque index (PI) and clinical attachment level (CAL) were recorded, and also gingival crevicular fluid (GCF) samples were collected at baseline and 6w after SRP. Total antioxidant capacity (TAOC) and total oxidative status (TOS) in GCF were analyzed. PBMT + SRP groups showed a statistically significant decrease in PPD and CAL, not in GI and PI compared with SRP alone. There were no statistically significant differences between smokers and nonsmokers in clinical data at six weeks after treatment. Although TAOC levels were increased in PMBT groups, TOS levels were decreased in all groups at the comparison of baseline and 6w after SRP. Adjunct use of 820 nm diode laser on SRP may improve the clinical parameters in smoker or nonsmoker patient with periodontitis.

The role of CRISPR-Cas in advancing precision periodontics

The significant advancement of molecular biology has revolutionized medicine and provided important technologies to further clinical research development. Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) are DNA sequences derived from bacteriophages which have previously infected the bacterial species. The CRISPR-Cas system plays a key role in bacterial defense by detecting and destroying DNA fragments during subsequent bacteriophage invasions. The Cas9 enzyme recognizes and cleaves new invading CRISPR-complementary DNA sequences. Researchers have taken advantage of this biological device to manipulate microbes' genes and develop novel therapeutics to tackle systemic disease. In this review, we discuss the potential of utilizing CRISPR-Cas systems in the periodontal field to develop personalized periodontal care. We summarize promising attempts to bring this technology to the clinical setting. Finally, we provide insights regarding future developments to best utilize the CRISPR-Cas systems to advance precision periodontics. Although further research is imperative to evaluate the safety and potential of using CRISPR-Cas to develop precision periodontics approaches, few studies showed promising data to support the investment into this important technology in the dental sector. CRISPR-Cas9 can be a useful tool to create knockouts in vitro and in vivo as a screening tool to identify cellular pathways involved in the pathogenesis of periodontitis. Alternative CRISPR systems such as CRISPRa, CRISPRi, and Cas13 can be used to modify the transcriptome and gene expression of genes involved in periodontitis progression. CRISPR systems such as Cas3 can be used to target the periodontal biofilm and to develop new strategies to reduce or eliminate periodontal pathogens. Currently, the utility of CRISPR-Cas applications in clinical settings is limited. Through this review, we hope to foster further discussion in the periodontal research and clinical communities with respect to the potential clinical application of novel, CRISPR-Cas based, therapeutics for periodontitis.

Potential Effect of Tobacco Consumption through Smoking and Chewing Tobacco on IL1beta Protein Expression in Chronic Periodontitis Patients: In Silico Molecular Docking Study

Detrimental effect of bad oral habits, such as smoking and chewing tobacco, on chronic periodontitis (CP) manifest chronic inflammation of gingival tissues which majorly results in gum bleeding, and teeth loss. A genetic association study of Interleukin 1 beta (IL1β) has been conducted in CP patients having smoking and chewing tobacco habits in regular life style. A molecular docking study has been consequently done to analyze the effect of tobacco on CP progression in depth. All statistical evaluation has been done by using SPSS v16.0. The findings of the study show the significant association of IL1β gene polymorphisms with CP increased susceptibility in combination of oral habits as mentioned earlier. The docking profile has showed the highest binding affinity of IL1β protein with the Nicotine derived Nitrosamine Ketone (NNK), one of the derivatives of nicotine which is in-taken through the habits associated with smoking and chewing tobacco. Nicotine, N-nitrosoanabasine, and N-nitrosonornicotine, the other derivatives, have also demonstrated significant impact over the IL1β protein-caused altered expression. Thus, this study concluded that the harmful effect of tobacco may increase the inflammation in periodontia by inducing the inflammatory active site of the IL1β protein in the CP patients.

Tooth survival and clinical outcomes up to 26 years after guided tissue regeneration therapy in deep intra-bony defects: Follow-up investigation of three randomized clinical trials

AIM

To investigate tooth survival and clinical long-term outcomes up to 26 years following guided tissue regeneration (GTR) therapy in deep intra-bony defects.

METHODS

Patients from three prospective clinical split-mouth studies, which investigated the outcomes of GTR therapy, were re-evaluated 21-26 years after surgery independent of the membrane type used, and tooth survival was assessed according to several site-specific and patient-related factors.

RESULTS

About 50 patients contributing 102 defects were available for this long-term follow-up. After up to 26 years (median 23.3 years), 52.9% of the teeth were still in situ. The median survival of the extracted teeth was 13.8 years. Patients with diabetes mellitus and/or smoking history lost significantly more teeth in the long term. Compared to the 1-year situation, there was no new median CAL loss after up to 26 years in the teeth which were still in situ.

CONCLUSIONS

Within the limitations of this study, our data show that more than 50% of the initially seriously diseased teeth were still in situ up to 26 years following GTR therapy despite an overall limited adherence to SPT. In the majority of these teeth, the CAL gain 1 year after GTR could be maintained over this long period.

Epigenetic reprogramming in periodontal disease: Dynamic crosstalk with potential impact in oncogenesis

Periodontitis is a chronic multifactorial inflammatory disease associated with microbial dysbiosis and characterized by progressive destruction of the periodontal tissues. Such chronic infectious inflammatory disease is recognized as a major public health problem worldwide with measurable impact in systemic health. It has become evident that the periodontal disease phenotypes are not only determined by the microbiome effect, but the extent of the tissue response is also driven by the host genome and epigenome patterns responding to various environmental exposures. More recently there is mounting evidence indicating that epigenetic reprogramming in response to combined intrinsic and environmental exposures, might be particularly relevant due its plasticity and potential application towards precision health. The complex epigenetic crosstalk is reflected in the prognosis and progress of periodontal diseases and may also lead to a favorable landscape for cancer development. This review discusses epigenomics modifications focusing on the role of DNA methylation and pathways linking microbial infection and inflammatory pathways, which are also associated with carcinogenesis. There is a more clear vision whereas 'omics' technologies applied to unveil relevant epigenetic factors could play a significant role in the treatment of periodontal disease in a personalized mode, evidencing that public health approach should coexist with precision individualized treatment.

Periodontal condition and recurrence of periodontitis associated with alcohol consumption in periodontal maintenance therapy

Background

This study followed individuals in periodontal maintenance therapy (PMT) over 6 years and longitudinally evaluated the effects of the frequency of alcohol consumption on the recurrence of periodontitis (RP).

Material and Methods

From a 6-year follow-up cohort study with 268 individuals under PMT, 142 patients who attended at least one PMT visit within 12 months were determined to be eligible. Based on their alcohol consumption, participants were categorized into 3 groups: none or occasional alcohol use (NA; n=88), moderate alcohol use (MA; n=26) and intense alcohol use (IA; n=24). Complete periodontal examination and alcohol consumption were evaluated at 2 times, T1 (after active periodontal therapy) and T2 (6 years).

Results

The frequencies of RP in the NA, MA and IA groups were 46.5%, 57.6%, and 79.1%, respectively. The following variables were significantly associated with RP in final multivariate logistic regression model: age >50 years old (OR = 1.79; 95%CI 1.42-2.91; p=0.002), current smoking (OR = 2.42; 95%CI 1.33-4.31; p=0.001), and intensive alcohol use (OR = 1.96; 95%CI: 1.37-2.64; p=0.024). Interaction between intensive alcohol use and smoking showed a high OR estimate of 3.15 (95%CI 1.29-6.32) for RP.

Conclusions

IA individuals undergoing PMT presented worse periodontal condition, higher rates of RP and tooth loss when compared to NA individuals. Additionally, the interaction between intensive alcohol use and smoking significantly increased the risk for RP.

Key words:Periodontitis, alcohol consumption, maintenance, epidemiology.

Factors affecting decision making at reassessment of periodontitis. Part 2: interpretation of clinical findings - systemic factors

This paper is the second in a four-part series outlining treatment planning at periodontal reassessment. The first article focussed on the information that should be gathered at the reassessment appointment. Treatment can involve a range of non-surgical and surgical approaches. A variety of general, practical and local site factors can affect the choice of one option over another in choosing the most predictable treatment option. Residual periodontal probing depths can be associated with both systemic and local factors. This article (part 2) outlines systemic factors that need to be assessed when faced with residual periodontal probing depths.

Periodontitis in individuals with liver cirrhosis: A case-control study

AIM

The aim of this study was to evaluate the association between liver cirrhosis and periodontitis.

METHODS

This case-control study included 294 individuals, 98 cases with liver cirrhosis and 196 controls. A full-mouth periodontal examination was performed and plaque index, probing depth, clinical attachment level and bleeding on probing were recorded. The association of risk variables with periodontitis was tested through univariate analysis and multivariate logistic regression, stratified by alcohol status.

RESULTS

A high prevalence of periodontitis was observed among cases (62.2%) when compared to controls (41.8%). Individuals with cirrhosis presented a chance ~2 higher of having periodontitis than controls (OR = 2.28; 95% CI 1.39-3.78; p < .001). Significant variables associated with periodontitis in the final logistic models were as follows: (a) no/occasional alcohol use model-number of teeth up 14, age ≥45-55 years, male sex and smoking; (b) moderate and intensive alcohol use models-cirrhosis, number of teeth up 14, age ≥45-55 years, male sex and smoking.

CONCLUSIONS

An important risk association between liver cirrhosis and periodontitis was observed. Additionally, the intensive alcohol use significantly increased the risk for periodontitis.

Periodontitis: A Multifaceted Disease of Tooth-Supporting Tissues

Periodontitis is an infection-driven inflammatory disease in which the composition of biofilms plays a significant role. Dental plaque accumulation at the gingival margin initiates an inflammatory response that, in turn, causes microbial alterations and may lead to drastic consequences in the periodontium of susceptible individuals. Chronic inflammation affects the gingiva and can proceed to periodontitis, which characteristically results in irreversible loss of attachment and alveolar bone. Periodontitis appears typically in adult-aged populations, but young individuals can also experience it and its harmful outcome. Advanced disease is the major cause of tooth loss in adults. In addition, periodontitis is associated with many chronic diseases and conditions affecting general health.

Lifestyle and periodontitis: The emergence of personalized periodontics

Personalized medicine is a medical model that involves the tailoring of healthcare - with medical decisions, practices, and/or products being customized to an individual patient. In this model, diagnostic testing is often employed for selecting appropriate and optimal therapies based on the context of a patient's genetic content or other epidemiologic, sociologic, molecular, physiologic, or cellular analyses. With the advent of major advances in periodontal medicine, including genomic discoveries and greater understanding of the multifactorial nature of periodontitis, it seems that the time is ripe to use personalized medicine as a model for personalized periodontics. This volume of Periodontology 2000 explores how new advances in our understanding of periodontitis within a medical model can evolve into new treatment strategies tailor-made for individual patients and not merely based on wholesale treatment paradigms.