Periodontitis and platelet count: A new potential link with cardiovascular and other systemic inflammatory diseases

Infectious and Immunological Links Between Periodontitis and COVID-19: A Review

Emerging evidence suggests a potential association between periodontitis and adverse outcomes in COVID-19. Both conditions share risk factors and exhibit similar immune dysregulation, including elevated pro-inflammatory cytokines, altered myeloid compartments, and T-cell dysfunction. SARS-CoV-2 uses angiotensin-converting enzyme type 2 and transmembrane protease serine 2 membrane proteins, highly expressed in the oral cavity, for cellular entry. Periodontitis may exacerbate COVID-19 through mechanisms such as oral microbe aspiration, increased viral receptor expression, and systemic inflammation. The shared immunopathogenesis, characterized by cytokine storms and perturbed immune profiles, suggests periodontitis can predispose patients to more severe COVID-19 outcomes. This article aims to review the associations between periodontitis and the severity of COVID-19 and the possible immune mechanisms involved.

Glucagon-Like Peptide 1 Receptor Agonists (GLP-1RAs) Improve Periodontal and Peri-Implant Health in Type 2 Diabetes Mellitus

Type 2 diabetes mellitus (T2DM) affects millions globally and is strongly associated with oral health issues, particularly periodontitis. The bidirectional relationship between T2DM and periodontitis is well established, with poorly managed T2DM increasing the risk of inflammation, tissue damage, and dental implant failure. Advances in treatment, such as glucagon-like peptide 1 receptor agonists (GLP-1RAs), have led to better glycemic control and may reduce T2DM-related complications, highlighting their potential in addressing interconnected oral-systemic health challenges. This narrative review critically evaluates the literature on the impact of GLP-1RAs on periodontal and peri-implant health. 10 in vitro studies, nine preclinical animal studies, and one clinical study were explored to investigate their effects on periodontal regeneration, implant therapy, and related mechanisms. In vitro research revealed that GLP-1RAs, including exenatide and liraglutide, promoted osteogenic differentiation of periodontal ligament stem cells (PDLSCs) through pathways such as the mitogen Wnt/β-catenin and mitogen-activated protein kinase pathways, even in high glucose or inflammatory conditions. Synergistic effects with stromal cell-derived factor-1 further promoted PDLSC proliferation and bone regeneration. Animal studies demonstrated that GLP-1RAs mitigated periodontal inflammation, oxidative stress, and alveolar bone resorption while promoting bone remodeling and implant osseointegration, independently of glycemic control. Importantly, advanced delivery systems, such as exenatide-loaded chitosan-poly(lactic-coglycolic acid) microspheres, further increased peri-implant osseointegration in diabetic models. The sole clinical study, a retrospective cohort study, assessed peri-implant marginal bone loss in peri-implantitis patients treated with different hypoglycemic drugs. Results showed significantly less clinical and radiographic bone loss in the GLP-1RA group compared to insulin and metformin groups (p < 0.01). Overall, while GLP-1RAs have promising anti-inflammatory, osteoprotective, and pleiotropic properties, their role appears more aligned with preserving periodontal and peri-implant health in T2DM individuals than directly treating periodontitis or peri-implantitis. By delineating current evidence and research directions, this review calls for medical and dental professionals to collaborate in leveraging these novel treatment options in future studies to improve patient care and address the intricate challenges that diabetes presents to oral health.

Treatment of periodontitis ameliorates the severity and extent of psoriasis-A randomized clinical trial

AIM

To assess the impact of non-surgical periodontitis treatment over conventional dermatological treatment on the severity and extent of psoriasis in patients affected by comorbid psoriasis and periodontitis.

METHODS

Seventy-four patients affected by both psoriasis and Stages I-IV periodontitis were randomized to receive either Steps 1-2 (non-surgical) of periodontal therapy (test group; n = 37) or no treatment (control group; n = 37). The two groups were balanced in terms of psoriasis medications, with the majority of the included patients undergoing biologics (74.0%) as monotherapy, while minor proportions were under systemic medications (13.7%) or none/topical/phototherapy (12.3%). The psoriasis area severity index (PASI) was regarded as the primary outcome. The Body Surface Area (BSA) and the Dermatology Life Quality Index (DLQI) were additionally considered as dermatological outcomes. Probing pocket depth, recession depth, clinical attachment level, periodontal inflamed surface area, and full-mouth plaque and bleeding scores were also measured. [Correction added on July 5, 2024, after first online publication: The preceding sentence has been revised].

RESULTS

Periodontal therapy in the test group led to statistically significant lower PASI scores at 10 weeks (mean = 3.15; standard deviation [SD] = 3.78) compared to the control group (mean = 7.11; SD = 6.09) (mean difference [MD] = -4.0; 95% confidence interval [CI]: -6.3, -1.6; p = .001). The test group also showed improvements in BSA (MD = -4.3) and periodontal parameters compared to the control group. DLQI only showed a non-statistically significant tendency (MD = -2.0).

CONCLUSION

Steps 1-2 of periodontal therapy showed an additional effect over conventional dermatological treatment in reducing the severity and extent of psoriasis (Clinicaltrials.gov: NCT05311501).

Flavonoid gossypetin protects alveolar bone and limits inflammation in ligature-induced periodontitis in mice

BACKGROUND

Bacterial-induced inflammation instigates the destruction of hard and soft tissues surrounding teeth in periodontitis. In severe cases, the increased number and activity of osteoclasts induces the resorption of alveolar bones, ultimately leading to tooth loss. Because of their diverse chemical structures and bioactivities, natural compounds are often suggested to treat a wide variety of diseases, including inflammatory disorders.

METHODS

In the present study, we demonstrated an inhibitory effect of gossypetin, a hexahydroxy flavone, on osteoclast differentiation and bone resorption using in vitro culture of osteoclasts from mouse bone marrow macrophage (BMM) precursors and in vivo model of ligature-induced periodontitis in mice.

RESULTS

Gossypetin significantly reduced the differentiation of osteoclasts from mouse BMM precursors in the presence of the receptor activator of nuclear factor κB ligand (RANKL). In vitro, gossypetin inhibited critical signaling events downstream of RANKL including the auto-amplification of nuclear factor of activated T-cells, cytoplasmic 1, Ca2+ oscillations, and the generation of reactive oxygen species. In a mouse ligature-induced periodontitis model, the administration of gossypetin significantly reduced osteoclastogenesis and alveolar bone resorption. Furthermore, gossypetin prevented the ligature-induced increase in macrophages and T cells and reduced the production of tumor necrosis factor-α and interleukin-6.

CONCLUSION

Taken together, these results show anti-osteoclastogenic and anti-inflammatory effects of gossypetin, suggesting the potential use of this natural compound in periodontitis.

Association of periodontal disease with the prognosis of chronic kidney disease: A meta-analysis

BACKGROUND

To assess the association between periodontal disease (PD) and the prognosis of chronic kidney disease (CKD).

METHODS

A systematic literature search was conducted using PubMed, Embase, and Cochrane Library to identify eligible cohort studies until April 2023. Relative risk (RR) with a 95% CI was used to evaluate the strength of the relationship between PD and CKD prognosis using the random-effects model.

RESULTS

Ten cohort studies involving 10 144 patients with CKD were selected for the meta-analysis. The summary results indicated that PD was associated with an increased risk of all-cause mortality in patients with CKD (RR: 1.32; 95% CI, 1.10-1.59; p = 0.003). Although no association was observed between PD and the risk of cardiac death in patients with CKD ( p = 0.180), while sensitivity analysis revealed PD may be associated with the risk of cardiac death (RR: 1.31; 95% CI, 1.05-1.64; p = 0.017). In addition, subgroup analyses revealed that the strength of the association of PD with the risks of all-cause mortality and cardiac death varies when stratified by region, sex, and CKD stage.

CONCLUSION

PD might exert a harmful effect on the risk of all-cause mortality, with a potential but unconfirmed association with cardiac death in patients with CKD.

Periodontal disease: A systemic condition

For decades, periodontitis has been considered to be a local inflammatory disease of the periodontal tissues in the oral cavity. Initially, associations of periodontitis with a multitude of noncommunicable diseases were each studied separately, and relationships were shown. The associations of periodontitis with morbidities, such as cardiovascular diseases, rheumatoid arthritis, diabetes mellitus, respiratory diseases, have been demonstrated. As most such studies were cross-sectional in nature, questions about causality cannot be univocally answered. And periodontitis as an independent risk factor for one systemic disease, becomes even more difficult to assess since recently periodontitis has also been associated with multimorbidity. Periodontitis and many systemic diseases share environmental, lifestyle and genetic risk factors, and share immunopathology. Moreover, suffering from one common noncommunicable disease may increase the susceptibility for another such chronic disease; the systemic effects of one condition may be one of various risk factors for another such disease. The overarching effect of any systemic disease is it causing a pro-inflammatory state in the individual; this has also been shown for periodontitis. Moreover, in periodontitis a prothrombotic state and elevated immunological activity have been shown. As such, when we consider periodontal disease as another systemic disease, it can affect the susceptibility and progression of other systemic diseases, and importantly, vice versa. And with this, it is not surprising that periodontitis is associated with a variety of other noncommunicable diseases. The medical definition of a systemic disease includes diseases that affect different organs and systems. Thus, the aim of this opinion paper is to propose that periodontitis should be considered a systemic disease in its own right and that it affects the individual's systemic condition and wellbeing. The dental and medical profession and researchers alike, should adapt this paradigm shift, advancing periodontal disease out of its isolated anatomical location into the total of chronic noncommunicable diseases, being for some conditions a comorbid disease and, vice versa, comorbidities can affect initiation and progression of periodontal disease.

Inflammation indices in association with periodontitis and cancer

Inflammation is a complex physiological process that plays a pivotal role in many if not all pathological conditions, including infectious as well as inflammatory diseases, like periodontitis and autoimmune disorders. Inflammatory response to periodontal biofilms and tissue destruction in periodontitis is associated with the release of inflammatory mediators. Chronic inflammation can promote the development of cancer. Persistence of inflammatory mediators plays a crucial role in this process. Quantification and monitoring of the severity of inflammation in relation to cancer is essential. Periodontitis is mainly quantified based on the severity and extent of attachment loss and/or pocket probing depth, in addition with bleeding on probing. In recent years, studies started to investigate inflammation indices in association with periodontal diseases. To date, only few reviews have been published focusing on the relationship between blood cell count, inflammation indices, and periodontitis. This review presents a comprehensive overview of different systemic inflammation indices, their methods of measurement, and the clinical applications in relation to periodontitis and cancer. This review outlines the physiological basis of inflammation and the underlying cellular and molecular mechanisms of the parameters described. Key inflammation indices are commonly utilized in periodontology such as the neutrophil to lymphocyte ratio. Inflammation indices like the platelet to lymphocyte ratio, platelet distribution width, plateletcrit, red blood cell distribution width, lymphocyte to monocyte ratio, delta neutrophil index, and the systemic immune inflammation index are also used in hospital settings and will be discussed. The clinical roles and limitations, relationship to systemic diseases as well as their association to periodontitis and treatment response are described.

Periodontitis and risk of cancer: Mechanistic evidence

This review aims to critically analyze the pathways of interaction and the pathogenic mechanisms linking periodontitis and oral bacteria with the initiation/progression of cancer at different body compartments. A higher risk of head and neck cancer has been consistently associated with periodontitis. This relationship has been explained by the local promotion of dysbiosis, chronic inflammation, immune evasion, and direct (epi)genetic damage to epithelial cells by periodontal pathobionts and their toxins. Epidemiological reports have also studied a possible link between periodontitis and the incidence of other malignancies at distant sites, such as lung, breast, prostate, and digestive tract cancers. Mechanistically, different pathways have been involved, including the induction of a chronic systemic inflammatory state and the spreading of oral pathobionts with carcinogenic potential. Indeed, periodontitis may promote low-grade systemic inflammation and phenotypic changes in the mononuclear cells, leading to the release of free radicals and cytokines, as well as extracellular matrix degradation, which are all mechanisms involved in carcinogenic and metastatic processes. Moreover, the transient hematogenous spill out or micro-aspiration/swallowing of periodontal bacteria and their virulence factors (i.e., lipopolysaccharides, fimbriae), may lead to non-indigenous bacterial colonization of multiple microenvironments. These events may in turn replenish the tumor-associated microbiome and thus influence the molecular hallmarks of cancer. Particularly, specific strains of oral pathobionts (e.g., Porphyromonas gingivalis and Fusobacterium nucleatum) may translocate through the hematogenous and enteral routes, being implicated in esophageal, gastric, pancreatic, and colorectal tumorigenesis through the modulation of the gastrointestinal antitumor immune system (i.e., tumor-infiltrating T cells) and the increased expression of pro-inflammatory/oncogenic genes. Ultimately, the potential influence of common risk factors, relevant comorbidities, and upstream drivers, such as gerovulnerability to multiple diseases, in explaining the relationship cannot be disregarded. The evidence analyzed here emphasizes the possible relevance of periodontitis in cancer initiation/progression and stimulates future research endeavors.

Systemic Immune-Inflammation Index and Systemic Inflammation Response Index are Associated With Periodontitis: Evidence From NHANES 2009 to 2014

INTRODUCTION AND AIMS

Periodontitis, a chronic inflammatory condition affecting the supporting structures of the teeth, is a substantial public health burrden whilst impacting the life quality of those affected. Elevated levels of systemic immune-inflammation index (SII) and systemic inflammation response index (SIRI) have been implicated in various inflammatory conditions. This study aimed to investigate the relationship between SII and SIRI with periodontitis.

METHODS

The study examined a total of 8666 participants in the 2009 to 2014 National Health and Nutrition Examination Survey (NHANES). The study compared the weighted prevalence of periodontitis among various groups. The association between SII, SIRI levels, and periodontitis was analyzed using binary logistic regression. Additionally, we explored nonlinear relationships between SII, SIRI, and the prevalence of periodontitis using restricted cubic spline (RCS) plots.

RESULTS

Among participants in the fourth quartile (Q4) of SII and SIRI, the highest prevalence of periodontitis was observed, with rates of 44.87% and 48.41%, respectively. After adjusting for all covariates, the odds ratio (OR) for periodontitis associated with SII Q4 was 1.19 (95% CI 1.02, 1.39, P = .03), while for SIRI Q4, it was 1.18 (95% CI 1.01, 1.39, P = .04). In addition, the results of sensitivity analysis revealed consistent findings, indicating that after adjusting for all covariates, the OR for periodontitis associated with SII Q4 and SIRI Q4 remained statistically significant. Specifically, the OR for periodontitis associated with SII Q4 was 1.19 (95% CI 1.02, 1.39, P = .03), while for SIRI Q4, it was 1.19 (95% CI 1.01, 1.40, P = .04).

CONCLUSIONS

These results indicate that elevated SII and SIRI levels are associated with an increased prevalence of periodontitis.

CLINICAL RELEVANCE

These findings suggest a potential connection between systemic inflammation and periodontitis, highlighting the importance of periodontitis patients being aware of their systemic diseases that are inflammatory in nature such as chronic cardiovascular afflictions.

Association between sleep and periodontitis: NHANES 2009-2014 and Mendelian randomization study

OBJECTIVE

We assessed association between periodontitis and sleep patterns.

METHODS

Our study included 7289 participants based on a large-scale study in NHANES. Periodontitis was defined through an oral examination. We used logistic regression to explore association between sleep status and risk of periodontitis. Further, stratified analysis was conducted. We performed a Mendelian randomization (MR) analysis using publicly available genetic data from corresponding studies.

RESULTS

Odds Ratio (OR) of periodontitis was 1.25 (1.07-1.46) in individuals with < 7 hours/per night. Stratification analysis showed individuals under 45 years old (OR: 1.28, 95% CI: 1.07-1.54), women (1.28(1.07-1.54)), education levels below high school (1.45(1.03-2.05)) and higher family income (-1.28(1.06-1.56)) were more likely to deteriorate to periodontitis if sleep time less than 7 hours. IVW-MR showed periodontitis risk was not associated with genetically increased levels of sleep time (0.22 (0.02-3.05)) or insomnia (0.83(0.55-1.24)).

CONCLUSION

There was no indication that sleep status was associated with periodontitis.

The long-term effect of periodontitis treatment on changes in blood inflammatory markers in patients with generalized aggressive periodontitis

BACKGROUND

Periodontitis is characterized by local inflammatory conditions in the periodontium, its severe form has been associated with elevated systemic inflammatory markers. However, the long-term effects of periodontal inflammation control on systemic inflammatory markers are unclear.

OBJECTIVE

This study aimed to investigate the long-term effects of periodontal therapy on the levels of peripheral venous blood inflammatory markers in patients with generalized aggressive periodontitis (GAgP), all of whom were now diagnosed as Stage III or IV Grade C periodontitis.

METHODS

Patients with GAgP were consecutively recruited from April 2013 to August 2014 (T0). Active periodontal treatment (APT) was provided, and follow-ups were conducted over a 3- to 5-year period (T1). Clinical parameters were assessed and fasting venous blood was collected at T0 and T1. Complete blood cell counts were obtained, and biochemical analyses were performed to evaluate the levels of serum components. The correlations between probing depth (PD) and hematological parameters were analyzed.

RESULTS

A total of 49 patients with GAgP completed APT and follow-ups. Probing depth (PD) reduced from 5.10 ± 1.07 mm at T0 to 3.15 ± 0.65 mm at T1. For every 1-mm reduction in PD after treatment, the neutrophil count, neutrophil-lymphocyte ratio, and total protein concentration were reduced by 0.33 × 109/L, 0.26, and 1.18 g/L, respectively. In contrast, the albumin/globulin ratio increased by 0.10.

CONCLUSION

This study indicated that periodontal therapy may have beneficial effects on peripheral venous blood inflammatory markers in patients with GAgP during long-term observation.

From Basic Science to Clinical Practice: A Review of Current Periodontal/Mucogingival Regenerative Biomaterials

Periodontitis is a dysbiosis-driven inflammatory disease affecting the tooth-supporting tissues, characterized by their progressive resorption, which can ultimately lead to tooth loss. A step-wise therapeutic approach is employed for periodontitis. After an initial behavioral and non-surgical phase, intra-bony or furcation defects may be amenable to regenerative procedures. This review discusses the regenerative technologies employed for periodontal regeneration, highlighting the current limitations and future research areas. The search, performed on the MEDLINE database, has identified the available biomaterials, including biologicals (autologous platelet concentrates, hydrogels), bone grafts (pure or putty), and membranes. Biologicals and bone grafts have been critically analyzed in terms of composition, mechanism of action, and clinical applications. Although a certain degree of periodontal regeneration is predictable in intra-bony and class II furcation defects, complete defect closure is hardly achieved. Moreover, treating class III furcation defects remains challenging. The key properties required for functional regeneration are discussed, and none of the commercially available biomaterials possess all the ideal characteristics. Therefore, research is needed to promote the advancement of more effective and targeted regenerative therapies for periodontitis. Lastly, improving the design and reporting of clinical studies is suggested by strictly adhering to the Consolidated Standards of Reporting Trials (CONSORT) 2010 statement.

Preventive and Therapeutic Potential of Streptococcus cristatus CA119 in Experimental Periodontitis in Rats

Periodontitis is an inflammatory condition of the oral cavity caused by a mixed infection of various bacteria, which not only severely affects the alveolar bone and connective tissues but also displays potential correlations with distal intestinal inflammation. In this study, we aimed to elucidate the therapeutic effects of Streptococcus cristatus CA119 on experimental periodontitis in rats and its impact on intestinal morphology. The results demonstrate that CA119 is capable of colonizing the oral cavity and exerting antagonistic effects on Porphyromonas gingivalis and Fusobacterium nucleatum, thus leading to a significant reduction in the oral pathogen load. Following CA119 intervention, there was a significant alleviation of weight loss in rats induced by periodontitis (P < 0.001). CA119 also regulated the expression of IL-6 (P < 0.05), IL-1β (P < 0.001), IL-18 (P < 0.001), COX-2 (P < 0.001), iNOS (P < 0.001), and MCP-1 (P < 0.01) in the gingival tissue. Additionally, CA119 reduced oxidative stress levels in rats and enhanced their antioxidant capacity. Microcomputed tomography (micro-CT) and histological analysis revealed that CA119 significantly reduced alveolar bone loss and reversed the downregulation of OPG/RANKL (P < 0.001). Furthermore, CA119 exhibited a significant protective effect against intestinal inflammation induced by periodontal disease and improved the colonic morphology in rats. In conclusion, this study demonstrates the role of CA119 as a potential oral probiotic in the prevention and treatment of experimental periodontitis, underscoring the potential of probiotics as a complementary approach to traditional periodontal care.

Multiplicative effect of stress and poor sleep quality on periodontitis: A university-based cross-sectional study

BACKGROUND

The aim of this study was to evaluate the association of perceived stress and poor sleep quality with periodontitis in a university-based cohort of individuals.

METHODS

A total of 235 individuals were included in this cross-sectional study. Perceived stress and sleep quality were evaluated through validated questionnaires, while periodontitis was identified with a full-mouth periodontal examination protocol using both European Federation of Periodontology/American Academy of Periodontology (EFP/AAP) and Centers for Disease Control and Prevention (CDC)/AAP case definitions. Simple and multiple linear and ordinal logistic regression analyses were performed to evaluate the association between perceived stress and sleep quality with periodontitis prevalence and severity.

RESULTS

Stage III/IV periodontitis resulted associated with both moderate/high perceived stress (odds ratio [OR] = 5.4; 95% confidence interval [CI]: 2.2-13.5; p < 0.001) and poor sleep quality (OR = 3.0; 95% CI: 1.2-7.4; p < 0.05). The interaction between moderate/high perceived stress and poor sleep quality presented a multiplicative association with stage III/IV periodontitis (EFP/AAP; OR = 5.8; 95% CI: 1.6-21.3; p < 0.001). Multiple linear regression analyses indicated a similar trend of association also with linear periodontal parameters, that is, mean clinical attachment level (CAL) and mean probing pocket depth (PPD).

CONCLUSIONS

The findings from the present study suggest that stress and poor sleep quality may exert a multiplicative effect on periodontitis prevalence and severity.

Alveolar bone loss and tooth loss contribute to increase in cancer mortality among older patients

BACKGROUND

Both cancer and periodontitis are more prevalent with age. Information on their relationship in older patients is limited. This study aims to examine whether periodontitis is associated with increased risk of cancer mortality with a ≥ 75-year age group cohort.

METHODS

A retrospective cohort study was conducted on 1146 patients who had digital radiographic examinations. Alveolar bone loss and loss of teeth were measured as indicators of periodontitis. Hazard ratio (HR) with 95% confidence interval (CI) were taken as the effect size to summarize the associations between periodontitis and risks of cancer mortality using the multivariate adjusted cox proportional hazards model and competing risk hazard model.

RESULTS

Totally, 104 total cancer, 28 lip, oral cavity and pharynx (LOP) cancer, 39 digestive cancer and 13 respiratory cancer cases were documented over 10 years of follow-up. Total cancer (HR 1.27, 95% CI 1.06-1.53) displayed statistically significant associations with alveolar bone loss and tooth loss after adjusting for relevant confounding variables. We also observed borderline significant association between alveolar bone loss and LOP cancer (HR 1.45, 95% CI 0.99-2.12). The above associations were consistent with the results observed from the competing risk hazard models.

CONCLUSION

Our results indicate that older patients suffering from tooth loss or alveolar bone loss are at increased risks of cancer mortality, especially for total cancer and LOP cancer.

The Development of Thermoresponsive Polymeric Simvastatin Prodrug for the Treatment of Experimental Periodontitis in Rats

Periodontitis (PD) is a severe inflammatory gum pathology that damages the periodontal soft tissue and bone. It is highly prevalent in the US, affecting more than 47% of adults. Besides routine scaling and root planing, there are few effective treatments for PD. Developed as an effective treatment for hyperlipidemia, simvastatin (SIM) is also known for its well-established anti-inflammatory and osteogenic properties, suggesting its potential utility in treating PD. Its clinical translation, however, has been impeded by its poor water-solubility, lack of osteotropicity, and side effects (e.g., hepatoxicity) associated with systemic exposure. To address these challenges, an N-(2-hydroxypropyl) methacrylamide (HPMA) copolymer-based thermoresponsive polymeric prodrug of SIM (ProGel-SIM) was developed as a local therapy for PD. Its aqueous solution is free-flowing at 4 °C and transitions into a hydrogel at ∼30 °C, allowing for easy local application and retention. After a thorough characterization of its physicochemical properties, ProGel-SIM was administered weekly into the periodontal pocket of an experimental rat model of PD. At 3 weeks post initiation of the treatment, the animals were euthanized with palate isolated for μ-CT and histological analyses. When compared to dose equivalent simvastatin acid (SMA, active form of SIM) treatment, the rats in the ProGel-SIM treated group showed significantly higher periodontal bone volume (0.34 mm3 vs 0.20 mm3, P = 0.0161) and less neutrophil (PMN) infiltration (P < 0.0001) and IL-1β secretion (P = 0.0036). No measurable side effect was observed. Collectively, these results suggest that ProGel-SIM may be developed as a promising drug candidate for the effective clinical treatment of PD.

The co-occurrence of the two main oral diseases: periodontitis and dental caries

OBJECTIVES

Limited studies are available testing through multiple regression models the association between the two main oral diseases: dental caries and periodontitis. The aim of this cross-sectional population-based study was to verify whether dental caries and periodontitis co-occur in a representative sample of the South Korea population.

MATERIALS AND METHODS

A total of 23,405 subjects representative of 36.2 million of adults (KNHANES) were examined. Univariate and multiple regression analyses using 7 different models were applied, controlling for age, gender, smoking status, frequency of toothbrushing, use of interproximal toothbrushes and flossing, educational level, income, gum diseases treatment and tooth filling in the previous year, BMI, Vitamin D serum levels, alcoholism, diabetes status, stress and carbohydrates dietary intake.

RESULTS

In the fully adjusted model, participants with periodontitis had, respectively, a mean of 0.82 (95% CI: 0.41-1.23) and of 0.36 (95% CI: 0.22-0.50) more untreated decayed surfaces and teeth than participants without periodontitis, with an OR to have at least one untreated decayed surface of 1.96 (95% CI: 1.66-2.32). However, cumulative caries experience (DF scores) and periodontitis were not associated.

CONCLUSIONS

In this large nationally representative population, periodontitis and untreated dental caries co-occur. However, when considering cumulative caries experience (DF scores), the two diseases do not appear related.

CLINICAL RELEVANCE

In light of their possible co-occurrence, clinicians should implement integrative diagnostic, preventive and treatment strategies for both diseases.

Systemic immune-inflammation index in patients with generalized stage III grade C periodontitis

OBJECTIVES

Systemic immune-inflammation index (SII) is a novel, inflammatory biomarker whose role in predicting several chronic systemic diseases has been recently identified. However, its association with generalized stage III grade C periodontitis in young adults remains unknown.

MATERIAL AND METHODS

The study is a multicentered, double-blind, hospital-based case-control clinical study. Periodontal examination comprised of recording plaque index, sites with bleeding on probing, pocket depth and clinical attachment loss for patients with generalized stage III grade C periodontitis and periodontally healthy group. Complete blood counts were obtained and used for calculating SII, neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio. Collected data were then subjected to statistical analyses.

RESULTS

SII was significantly higher in patients with generalized stage III grade C periodontitis compared to periodontally healthy individuals (723.87 vs. 537.74 × 109 /L, p < 0.0001). SII is associated with severe periodontitis in young adults (odds ratio [OR]:11.86, 95% CI 9.61-20.76, p < 0.0001) after adjusting for factors found significant in univariate analysis. Receiver operative curve analysis demonstrated a fair predictive validity of SII in detecting generalized stage III grade C periodontitis in young adults (AUC: 0.766, 95%CI 0.731-0.799, p < 0.0001, sensitivity 81.27%, specificity 76.50% and diagnostic accuracy 78.89%). SII did not exhibit superior predictive validity when compared with NLR in the context of generalized stage III grade C periodontitis (AUC for SII: 0.766, 95%CI 0.731-0.799, AUC for NLR: 0.788, 95% CI 0.754-0.819; p = 0.28).

CONCLUSION

SII is associated with generalized stage III grade C periodontitis in young adults.

Revealing a potential necroptosis-related axis (RP11-138A9.1/hsa-miR-98-5p/ZBP1) in periodontitis by construction of the ceRNA network

BACKGROUND AND OBJECTIVES

Periodontitis, a prevalent chronic inflammatory condition, poses a significant risk of tooth loosening and subsequent tooth loss. Within the realm of programmed cell death, a recently recognized process known as necroptosis has garnered attention for its involvement in numerous inflammatory diseases. Nevertheless, its correlation with periodontitis is indistinct. Our study aimed to identify necroptosis-related lncRNAs and crucial lncRNA-miRNA-mRNA regulatory axes in periodontitis to further understand the pathogenesis of periodontitis.

MATERIALS AND METHODS

Gene expression profiles in gingival tissues were acquired from the Gene Expression Omnibus (GEO) database. Selecting hub necroptosis-related lncRNA and extracting the key lncRNA-miRNA-mRNA axes based on the ceRNA network by adding novel machine-learning models based on conventional analysis and combining qRT-PCR validation. Then, an artificial neural network (ANN) model was constructed for lncRNA in regulatory axes, and the accuracy of the model was validated by receiver operating characteristic (ROC) curve analysis. The clinical effect of the model was evaluated by decision curve analysis (DCA). Weighted correlation network analysis (WGCNA) and single-sample gene set enrichment analysis (ssGSEA) was performed to explore how these lncRNAs work in periodontitis.

RESULTS

Seven hub necroptosis-related lncRNAs and three lncRNA-miRNA-mRNA regulatory axes (RP11-138A9.1/hsa-miR-98-5p/ZBP1 axis, RP11-96D1.11/hsa-miR-185-5p/EZH2 axis, and RP4-773 N10.4/hsa-miR-21-5p/TLR3 axis) were predicted. WGCNA revealed that RP11-138A9.1 was significantly correlated with the "purple module". Functional enrichment analysis and ssGSEA demonstrated that the RP11-138A9.1/hsa-miR-98-5p/ZBP1 axis is closely related to the inflammation and immune processes in periodontitis.

CONCLUSION

Our study predicted a crucial necroptosis-related regulatory axis (RP11-138A9.1/hsa-miR-98-5p/ZBP1) based on the ceRNA network, which may aid in elucidating the role and mechanism of necroptosis in periodontitis.

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.

Periodontitis and low cognitive performance: A population-based study

AIM

To study the epidemiological association between periodontitis and low cognitive performance among older adults, within a representative sample of the U.S.

POPULATION

MATERIALS AND METHODS

Data from 2086 older adults (≥60 years old), representative of 77.1 million people, were retrieved from the NHANES 2011-2014 database. Periodontitis cases were identified and classified according to the AAP/CDC criteria (mild, moderate, and severe). Cognitive function was assessed through the Consortium to Establish a Registry for Alzheimer's disease (CERAD), the animal fluency test (AFT), the digit symbol substitution test (DSST), and the global cognition score. The lowest non-survey weighted quartile for each cognitive test was defined as low cognitive performance. Simple and multiple regression analyses were performed.

RESULTS

Moderate and severe periodontitis were significantly associated with a low DSST performance (OR = 1.66 and OR = 2.97, respectively). Each millimetre increase in mean CAL was associated with a lower AFT (OR = 1.44), DSST (OR = 1.86), and global cognition (OR = 1.50) performance.

CONCLUSIONS

The findings of the present study suggest the existence of an independent association between periodontitis and low cognitive performance among older adults (≥60 years old).

Development and external validation of prediction models for critical outcomes of unvaccinated COVID-19 patients based on demographics, medical conditions and dental status

Background

Multiple prediction models were developed for critical outcomes of COVID-19. However, prediction models using predictors which can be easily obtained in clinical practice and on dental status are scarce.

Aim

The study aimed to develop and externally validate prediction models for critical outcomes of COVID-19 for unvaccinated adult patients in hospital settings based on demographics, medical conditions, and dental status.

Methods

A total of 285 and 352 patients from two hospitals in the Netherlands were retrospectively included as derivation and validation cohorts. Demographics, medical conditions, and dental status were considered potential predictors. The critical outcomes (death and ICU admission) were considered endpoints. Logistic regression analyses were used to develop two models: for death alone and for critical outcomes. The performance and clinical values of the models were determined in both cohorts.

Results

Age, number of teeth, chronic kidney disease, hypertension, diabetes, and chronic obstructive pulmonary diseases were the significant independent predictors. The models showed good to excellent calibration with observed: expected (O:E) ratios of 0.98 (95%CI: 0.76 to 1.25) and 1.00 (95%CI: 0.80 to 1.24), and discrimination with shrunken area under the curve (AUC) values of 0.85 and 0.79, based on the derivation cohort. In the validation cohort, the models showed good to excellent discrimination with AUC values of 0.85 (95%CI: 0.80 to 0.90) and 0.78 (95%CI: 0.73 to 0.83), but an overestimation in calibration with O:E ratios of 0.65 (95%CI: 0.49 to 0.85) and 0.67 (95%CI: 0.52 to 0.84).

Conclusion

The performance of the models was acceptable in both derivation and validation cohorts. Number of teeth was an additive important predictor of critical outcomes of COVID-19. It is an easy-to-apply tool in hospitals for risk stratification of COVID-19 prognosis.

Air Pollution as a Risk Indicator for Periodontitis

BACKGROUND

Air pollutants can influence local and systemic inflammation, oxidative stress and microbiome composition. Therefore, air pollution may potentially represent an unexplored modifiable risk indicator for periodontitis. The aim of the current cross-sectional study was to investigate the epidemiological association between outdoor air pollution and periodontitis in a representative sample of the South Korean population.

METHODS

A total of 42,020 individuals, which were representative of 35.2 million South Koreans, were examined. The mean annual levels of particulate matter of 10 μm (PM10), ozone, sulfur dioxide (SO₂), nitrogen dioxide (NO₂) and humidity, were studied. Periodontitis was defined according to the Community Periodontal Index (CPI ≥ 3). Simple and multiple regression analyses using four different models were applied.

RESULTS

Every 5-μg/m³ increase in PM10 (OR = 1.17; 95% confidence interval-CI: 1.11-1.24) and of 0.005 ppm in ozone levels (OR = 1.4; 95% CI: 1.00-1.30) were positively associated with periodontitis prevalence. Conversely, every 5% increase in humidity (OR = 0.94; 95% CI: 0.90-0.99) and 0.003 ppm increase in NO₂ levels (OR = 0.93; 95% CI: 0.89-0.96) were inversely associated with periodontitis occurrence.

CONCLUSIONS

In this nationally representative population several air pollutants were found to be associated with periodontitis occurrence. Hence, the present results suggest that air pollution may be a new modifiable risk indicator for periodontitis.

Periodontitis and edentulism as risk indicators for mortality: Results from a prospective cohort study with 20 years of follow-up

AIM

To investigate the association between periodontitis and edentulism with cardiovascular disease (CVD) and all-cause mortality.

METHODS

Baseline data of 506 subjects including 256 angiographically verified coronary artery disease patients and 250 matched participants in cardiovascular health from the Kuopio Oral Health and Heart study were collected from 1995-1996. Mortality data were accrued until May 31, 2015, and related to baseline periodontal health and edentulism, assessed as exposure and collected by means of clinical and radiographic examination by a single examiner. Cox proportional hazards regression models were fit using covariates such as age, gender, smoking, BMI, and education. The final sample size for the periodontitis models ranged from 358 to 376, while the edentate models included 413 to 503 subjects for CVD and all-cause mortality, respectively with no missing values in the predictor, confounders, and outcome.

RESULTS

The strongest association was found between edentulism and CVD and all-cause mortality (HR: 1.9 ^CVD , HR: 1.6^all-cause ; p < .01).

CONCLUSIONS

Edentulism considered as a poor oral health marker was associated strongly with CVD mortality while periodontitis was not.

Near-Infrared-Enhanced Dual Enzyme-Mimicking Ag-TiO2-x@Alginate Microspheres with Antibactericidal and Oxygeneration Abilities to Treat Periodontitis

The effective treatment for periodontitis is to completely and sustainedly eradicate the bacterial pathogens from the complex periodontal pockets. Local sustained-release antibiotics as a complementary treatment after scaling and root planning can sustainedly combat bacterial pathogens in the periodontal pockets to help treat the disease, but the increasing concern of bacterial resistance limits its future use. Here, we reported a local antibacterial system based on microsized multifunctional Ag-TiO_2-x encapsulated in alginate (ATA) microspheres. We confirmed that ATA displayed strong photothermally enhanced dual enzyme-mimicking (peroxidase-like and catalase-like) activities and weak photocatalytic activity under 808 nm near-infrared (NIR) irradiation, which could boost the generation of reactive oxygen species (ROS) and O₂ in the presence of low-level H₂O₂. As a result, the ATA/H₂O₂/NIR system exhibited efficient antibacterial activity against Porphyromonas gingivalis and Streptococcus gordonii in both planktonic and biofilm forms. With the help of ROS, ATA could release Ag⁺ in concentrations sufficient to inhibit periodontal pathogens as well. Moreover, the in situ-generated oxygen was supposed to alleviate the local hypoxic environment and would help downregulate the lipopolysaccharide-mediated inflammatory response of periodontal stem cells. The in vivo rat periodontitis treatment results demonstrated that the ATA/H₂O₂/NIR system reduced the bacterial load, relieved inflammation, and improved tissue healing. Our work developed a new local prolonged bactericidal and oxygenation system for enhanced periodontitis. Avoiding the usage of antibiotics and nanomaterials, this strategy showed great promise in adjunctive periodontitis treatment and also in other biomedical applications.

Leisure-time and occupational physical activity demonstrate divergent associations with periodontitis: A population-based study

AIM

To evaluate the association between leisure-time/occupational physical activity (LTPA/OPA) and periodontitis in a nationally representative sample of the U.S.

POPULATION

MATERIALS AND METHODS

Data from 10,679 adults were retrieved from NHANES 2009-2014 database. Physical activity was assessed through the Global Physical Activity Questionnaire, and accordingly, subjects were classified as performing either high or low LTPA/OPA. Periodontal status was assessed through a full-mouth periodontal examination, and subjects were classified according to the AAP/CDC criteria (no, mild, moderate, or severe periodontitis). Simple and multiple regression analyses were applied to study the association between LTPA/OPA and periodontitis/severe periodontitis.

RESULTS

Multiple regression analyses identified high LTPA as a protective indicator for periodontitis (odds ratio [OR] = 0.81; 95% confidence interval [CI]: 0.72-0.92), while high OPA was found to be a significant risk indicator (OR = 1.16; 95% CI: 1.04-1.30). The combination low LTPA/high OPA showed a cumulative independent association with periodontitis (OR = 1.47; 95% CI: 1.26-1.72). Moreover, both high LTPA (OR = 0.72; 95% CI: 0.58-0.90) and high OPA (OR = 1.29; 95% CI: 1.09-1.53) were significantly associated with stronger estimates of severe periodontitis; the same was observed for the combination of low LTPA/high OPA (OR = 1.66; 95% CI: 1.29-2.15).

CONCLUSIONS

LTPA and OPA showed divergent associations with periodontitis.

Reference intervals of complete blood count parameters for individuals aged 80 to 89 years in Guizhou, China: A STROBE-compliant retrospective study

The reference intervals of complete blood count (CBC) parameters were commonly based on healthy individuals aged 20 to 79 years. However, these values are not optimal for correct clinical diagnosis in older individuals (e.g., 80-89 years). Although the reference intervals for this age group have been reported in China, there is no population-based report in Guizhou province. A total of 481 healthy adults (238 males and 243 females) aged 80 to 89 years were recruited from Affiliated Hospital of Zunyi Medical University in Guizhou. The CBC parameters were detected by Sysmex XN-9000 automatic hematology analyzer. The reference intervals of the components were analyzed according to the guidelines of International Federation of Clinical Chemistry. This study reported the reference intervals of CBC parameters. There were significant differences were examined in some reference intervals between the different gender groups, especially for RBC-related parameters. Compared with national standards, the most of all conventional reference intervals for CBC parameters were decreased. The present study provided the local reference intervals of CBC parameters for individuals aged 80 to 89 years in Guizhou, China. Some of our results were sex-specific, and most of our results show lower values while comparing with commonly used reference intervals in China. Therefore, more attentions should be paid to these differences, and accurate reference intervals will facilitate clinical diagnosis and decision-making in these populations.

HIF-1α drives the transcription of NOG to inhibit osteogenic differentiation of periodontal ligament stem cells in response to hypoxia

Osteogenic differentiation of periodontal ligament stem cells (PDLSCs) is limited in hypoxia, and HIF-1α is key to the response to hypoxia. However, its mechanisms remain largely unknown. This study discovered an osteogenesis-related gene sensitive to hypoxia in PDLSCs, and investigated the molecular mechanisms between HIF-1α and the gene. NOG, a gene that negatively regulates osteogenesis, was discovered by RNA-seq. Under normoxic conditions, HIF-1α overexpression led to enhanced expression of NOG/Noggin and inhibited the expression of osteogenesis-related genes, while inhibition of HIF-1α reversed this effect. The expression of HIF-1α, NOG/Noggin and the osteogenesis-related genes were detected by qRT-PCR or Western blot. Mechanistically, we verified that HIF-1α binds to the hypoxia response element (-1505 to -1502) in the promotor of NOG to enhance secretion of Noggin by chromatin immunoprecipitation and a dual-luciferase reporter assay. IHC staining findings in an animal model verified that Noggin-associated osteogenic differentiation was inhibited in hypoxia. NOG displayed a concordant relationship with HIF-1α, and secreted more with increasing of HIF-1α. Hypoxia stabilized HIF-1α, which bound to the HRE (-1505 to -1502) of the NOG promotor to enhance NOG transcription resulted in inhibiting osteogenic differentiation of PDLSCs. This study offers a promising therapy for periodontitis.

Periodontitis and COVID-19: Biological Mechanisms and Meta-analyses of Epidemiological Evidence

Since the beginning of 2020, the entire global health care system has been severely challenged by the outbreak of coronavirus 2019 disease (COVID-19). Robust evidence has demonstrated a more severe course of COVID-19 in the presence of several comorbidities, such as cardiovascular diseases, diabetes mellitus, and obesity. Here, we critically appraise the recent research discoveries linking periodontitis to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and to severe COVID-19, with a special focus on the associated biological mechanisms and the available epidemiological evidence. SARS-CoV-2 main receptors and coreceptors (ACE2, TMPRSS2, furin, CD147) are overexpressed in periodontal tissues of periodontitis patients, with inflammation, periodontal pathogens, and damage-induced pyroptosis triggering a positive feedback loop. However, meta-analyses of epidemiological studies only indicated a nonstatistically significant tendency for an increased risk of SARS-CoV-2 infection in subjects with periodontitis (odds ratio [OR] = 1.69; 95% CI, 0.91-3.13, P = 0.09). Furthermore, periodontitis may worsen clinical COVID-19 courses through multiple direct and indirect pathways, including damage to lower airways due to aspiration of periodontal pathogens, exacerbation of the cytokine storm via the low-grade chronic systemic inflammation, and SARS-CoV-2 dissemination through the ulcerated gingival epithelium with consequent induced pulmonary vessels vasculopathy. Indeed, meta-analyses of epidemiological studies indicated that periodontitis subjects are more likely to experience a more severe course of COVID-19. Specifically, periodontitis was associated with a 4-fold increased odds of hospitalization (OR = 4.72; 95% CI, 1.11-20.03, P = 0.04), 6-fold of requiring assisted ventilation (OR = 6.24; 95% CI, 2.78-14.02, P = 0.00), and more than 7-fold of death due to COVID-19 complications (OR = 7.51; 95% CI, 2.16-26.10, P = 0.00). The breakthrough analyzed here emphasizes the relevance of the mouth-systemic connection as a target to mitigate the current COVID-19 emergency and the future predicted coronavirus pandemics.

Associations between self-reported periodontal disease and nutrient intakes and nutrient-based dietary patterns in the UK Biobank

AIM

To examine the cross-sectional associations between single nutrient intakes and posteriori nutrient-based dietary patterns and periodontal disease risk in a subset of the UK Biobank cohort.

MATERIALS AND METHODS

Dietary data were collected by 24-h dietary recall on up to five separate occasions over 16 months. A touchscreen questionnaire was used to collect oral health information. Participants were considered at high risk of periodontal disease if they reported having painful gums and/or bleeding gums and/or loose teeth. Principal component analysis identified four nutrient-based dietary patterns from 20 nutrients. Logistic regression was used to estimate the odds ratio of periodontal disease risk for single nutrients and nutrient-based dietary patterns.

RESULTS

A total of 9476 participants (mean age 56.2 years [SD 8.0]) were included in the analysis. Higher intakes of vitamin B6, B12, C, and E, folate, iron, potassium, magnesium, polyunsaturated fatty acids, and total sugar were associated with a lower risk of periodontal disease. Higher intake of saturated fat was associated with an increased risk. A dietary pattern characterized by high micronutrients and fibre intake was associated with low risk of periodontal disease.

CONCLUSION

Within this sample of middle-aged and older adults, a "high micronutrient and fibre" dietary pattern was associated with reduced risk of periodontal disease.

Shared microbiological and immunological patterns in periodontitis and IBD: A scoping review

OBJECTIVES

To extract the microbiological and immunological evidence underpinning the association between periodontitis and inflammatory bowel disease (IBD).

METHODS

Relevant articles were sorted through a systematic search on PubMed, Embase, Scopus and Web of Science up to October 2020. Available evidence was grouped in three different clusters: (a) studies that examined oral microbial alterations in IBD patients; (b) studies that investigated intestinal dysbiosis in patients with periodontitis; and (c) evidence for a shared immunological pattern between the two conditions.

RESULTS

A total of 15 studies involving 1,171 patients were included. Oral microbiome, either subgingival or salivary, was consistently altered in patients with IBD compared to healthy subjects (a) Additionally, gut dysbiotic microbiota of IBD patients was colonized by pathobionts from oral origin, either via haematogenous or enteric route. Suffering from periodontitis is associated with lower alpha diversity in the gut microbiome (b) Lastly, both IBD and periodontitis are characterized by similar expression patterns of inflammatory cytokines at the gingival and gut levels that are exacerbated when both diseases are present (c).

CONCLUSIONS

Periodontitis and IBD share common dysbiotic and immunological traits. Well-designed preclinical models and longitudinal cohort studies are required to better explore the causal pathways between the two conditions (PROSPERO CRD42020194379).

Managing the Systemic Impact of Periodontitis

Periodontitis is a microbially driven host-mediated disease that leads to loss of periodontal attachment and bone. It is associated with elevation of systemic inflammatory markers and with the presence of systemic co-morbidities. Furthermore, periodontal treatment leads to a 24-48 h-long acute local and systemic inflammatory response. This systemic response might increase the burden of patients with compromised medical history and/or uncontrolled systemic diseases. The correlation between periodontitis and systemic diseases, the impact of periodontitis on the quality of life and public health, the effects of periodontal treatment on systemic health and disease, and the available methods to manage systemic inflammation after periodontal therapy are discussed. The main focus then shifts to a description of the existing evidence regarding the impact of periodontitis and periodontal treatment on systemic health and to the identification of approaches aiming to reduce the effect of periodontitis on systemic inflammation.

P. G, Rahman W. Clinical and diagnostic significance of blood leukocyte ratios in young patients with stage III grade C periodontitis

OBJECTIVES

Blood leukocyte ratios have been recently proposed as simple, rapid, cheap and easily accessible biomarkers of systemic inflammation. However, little is known about the relationship of neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR) and lymphocyte-monocyte ratio (LMR) with periodontitis, which might not only serve as the potential biomarkers of systemic inflammation but also aid in diagnosis/screening of severe periodontitis. Hence, the purpose of this study was to evaluate the differences in the serum levels of these leukocyte ratios in healthy subjects and patients with generalized stage III Grade C periodontitis, and their applicability in identifying patients with the risk of developing severe periodontitis.

MATERIAL AND METHODS

The subjects were categorized into case and control group. Clinical parameters including Plaque index (PI), modified Gingival Index (mGI), Mean ratio of bleeding sites, Probing Pocket depth (PPD) and the clinical attachment loss (CAL) were assessed in both the groups. Venous blood samples were collected from subjects from both groups for the biochemical analysis and blood leukocyte ratios- NLR, PLR and LMR were calculated. The values were then subjected to statistical analysis.

RESULTS

The results showed significantly higher NLR and lower LMR values in patients with generalized stage III grade C periodontitis. Both the blood leukocyte ratios were moderately associated with increasing clinical parameters of periodontal disease. However, the values of PLR, although found to be higher in the periodontitis group, did not make a significant difference when compared with periodontally healthy subjects. The cut-off value of >2.15 for NLR and <7.16 for LMR fairly predicted the risk of severe periodontitis in young adults.

CONCLUSIONS

NLR and LMR can provide a new insight into the relationship between periodontitis and systemic diseases and can be of potential diagnostic value in identifying patients with severe periodontitis of younger age group.

Periodontitis is a factor associated with dyslipidemia

OBJECTIVE

To investigate the association between the severity of periodontitis (exposure) and dyslipidemia (outcome).

METHODS

This was a cross-sectional study of users of public health services. Periodontitis was defined using the Center for Disease Prevention and Control and the American Academy of Periodontology criteria. Lipid evaluation used data on systemic biomarkers. Dyslipidemia diagnosis was based on the Guidelines of total cardiovascular risk of the World Health Organization. Weight, height, waist circumference, and blood pressure were measured, and socioeconomic-demographic, lifestyle behavior factors, general and oral health conditions of the participants were collected. Hierarchical and logistic regression analyzes were used to determine the association between the exposures and the outcome. Odds Ratios, unadjusted and adjusted, and 95% confidence intervals were estimated.

RESULTS

Of 1,011 individuals examined, 75.17% had dyslipidemia, and 84.17% had periodontitis, 0.2% with mild, 48.56% moderate, and 35.41% severe disease. The association between periodontitis and dyslipidemia was maintained through hierarchical analysis and in the multiple regression modeling, showing that the occurrences of dyslipidemia in the group with periodontitis, and its moderate and severe levels, were, respectively, 14%, 30%, and 16% higher compared with those without periodontitis.

CONCLUSIONS

The results showed a positive association between moderate and severe periodontitis and dyslipidemia.

Blood and Salivary Inflammatory Biomarkers Profile in Patients with Chronic Kidney Disease and Periodontal Disease: A Systematic Review

Introduction: Periodontitis is the most prevalent inflammatory disease worldwide. Its inflammatory levels spread systemically, which can be associated with chronic kidney disease. Biomarkers have the potential to diagnose and correlate periodontitis and chronic kidney disease, helping to monitor systemic inflammation. Thereby, this study aimed to analyze the association between chronic kidney disease and periodontitis by conducting a biomarker analysis on blood and saliva. Material and methods: An electronic search through PubMed/MEDLINE, EMBASE, and Web of Science databases was conducted to identify clinical studies published in the last ten years, with no language restrictions. Twelve articles met all the inclusion criteria, two randomized controlled trials, one cohort study, and nine observational studies. Results: The studies included a total of 117 patients for saliva biomarkers, with a mean age of approximately 57 years old, and 56.68% of the subjects were female. After analyzing all the included studies, it was possible to verify the following biomarkers assessed: CRP, WBC, fibrinogen, IL-4 and -6, cardiac troponin T, NOx, ADMA, albumin, osteocalcin, cystatin C, PGLYRP1, cholesterol, HDL, LDL, triglycerides, and hemoglobin. Conclusion: A direct cause–effect association between periodontitis and CKD could not be established. However, it was possible to conclude that there was a correlating effect present, through the analyzed biomarkers.

Comparison of blood parameters between periodontitis patients and healthy participants: A cross-sectional hematological study

Background

Bacteria and their products involved in periodontitis evoke an immunoinflammatory response in the host tissue. Inflammatory diseases, such as periodontitis, are often not just a local event, but may have systemic ramifications, including elevations in the numbers of circulating leukocytes, acute-phase proteins and oxidative stress markers. It is now emerging that also erythrocytes are affected by chronic inflammatory diseases. This phenomenon, named "anemia of inflammation," is not caused by marrow deficiencies or other diseases. The present study aimed to assess whether there was any relation between chronic periodontitis and hematological parameters.

Materials and Methods

A total of 80 patients were included in the study and were divided into the healthy and periodontitis groups. Blood sample was obtained from each participant for hematological analysis of leukocytes, erythrocytes, platelets, red blood cell (RBC) distribution width (RDW), mean corpuscular volume (MCV), platelet count and neutrophil-leukocyte ratio (NLR). Further, the values were gathered and subjected to statistical analysis. Unpaired t-test was performed to assess the statistical significance between the groups and P < 0.05 and < 0.001 were considered to be statistically significant.

Results

Results show statistically significant difference seen in leukocytes, lymphocytes, RDW, MCV, platelet count and NLR which was higher in patients with periodontitis, all other parameters are nonsignificant.

Conclusion

Thus, within limitations, it can be concluded that increased levels of leukocytes, lymphocytes, RDW, MCV, platelet count and NLR depict the inflammatory state and destructive nature of periodontitis.

Isolated Systolic Blood Pressure and Red-Complex Bacteria-A Risk for Generalized Periodontitis and Chronic Kidney Disease

Hypertension is a risk factor for generalized periodontitis (GP) and chronic kidney diseases (CKD). However, the role of isolated systolic blood pressure as one of the major risks for these inflammatory diseases has not been explored. Very limited studies exist identifying the red-complex bacteria in association with the isolated systolic blood pressure. Hence, the main objective of this study was to assess the isolated systolic blood pressure and the red-complex bacteria along with the demographic variables, periodontal parameters, and renal parameters in patients with generalized periodontitis and chronic kidney disease. One hundred twenty participants (age 30-70 years) were divided into four groups-Group C: control (systemically and periodontally healthy subjects), Group GP: generalized periodontitis, Group CKD: subjects with CKD with good periodontal health, Group CKD + GP: subjects with both generalized periodontitis and CKD. Demographic variables and periodontal parameters were measured and recorded. Blood pressure measurements and a detailed history and renal parameters such as serum creatinine, eGFR, and fasting blood sugar were recorded. The red-complex bacteria (RCB) were assessed in the subgingival plaque samples of all four groups using RT-PCR. Older participants (above 50 years) showed worse periodontal scores in the CKD + GP group along with elevated isolated systolic blood pressure, higher serum creatinine, and fasting blood sugar. eGFR was significantly decreased compared to the other groups. Bacterial counts were higher in the GP + CKD group, suggesting that they may be at a higher risk for generalized periodontitis and chronic kidney disease. Isolated systolic blood pressure (ISBP) and RCB were significantly correlated with the renal and periodontal parameters. A log-linear relationship exists between periodontal disease, CKD, RCB, and isolated systolic hypertension levels.

Macro and trace elements signature of periodontitis in saliva: A systematic review with quality assessment of ionomics studies

Objectives

The present systematic review examined the available evidence on distinctive salivary ion profile in periodontitis compared to periodontal health and provided a qualitative assessment of the literature.

Background

Macro and trace elements are essential for cellular physiology, and their changes in biological fluids can be revelatory of an underlying pathological status.

Methods

Data from relevant studies identified from PubMed, Embase, and Scopus databases were retrieved to answer the following PECO question: “In systemically healthy individuals, are there any differences in any salivary macro or trace element concentration between periodontally healthy subjects (H) and patients with periodontitis (P)?” Quality of included studies was rated using a modified version of the QUADOMICS tool. A consistency analysis was performed to identify significantly discriminant chemical elements.

Results

After the screening of 873 titles, 13 studies were included reporting data on 22 different elements. Among them, levels of sodium and potassium were consistently and significantly higher in P compared to H. Conflicting results were found for all the other elements, despite concentration of calcium, copper, and manganese mostly increased in saliva of P. Levels of magnesium were found higher in P than in H in 2 studies but lower in 3. Zinc resulted significantly increased in saliva from H compared to P individuals in 2 studies, but one study reported opposite results. Four studies were considered as high quality, while reporting of operative protocols and statistical analysis was a major limitation for the others. Due to high methodologic heterogeneity, meta‐analysis was not performed.

Conclusions

Levels of macro or trace elements were differentially identified in saliva across diverse periodontal conditions, having a major potential for investigation of oral homeostasis and for high‐resolution periodontal diagnosis. Products of inflammatory physiologic cellular impairment, such as sodium and potassium, were the most consistently associated with periodontitis (PROSPERO CRD42021235744).

Pretreatment Systemic Immune-Inflammation Index Predict Needs for Teeth Extractions for Locally Advanced Head and Neck Cancer Patients Undergoing Concurrent Chemoradiotherapy

BACKGROUND

To evaluate the utility of pretreatment systemic immune-inflammation index (SII) in predicting the teeth caries and need for tooth extraction after concurrent chemoradiotherapy (C-CRT) for locally advanced squamous-cell head and neck cancer (LA-SCHNC) patients.

METHODS

The records of LA-SCHNC patients who underwent formal dental evaluations at pre- and post-C-CRT periods were retrospectively analyzed. The pretreatment SII values were calculated using the platelet, neutrophil, and lymphocyte measures acquired on the first day of C-CRT: SII=Platelets×neutrophils/lymphocytes. Receiver operating characteristic (ROC) curve analysis was employed to identify the ideal pre-C-CRT SII cutoff that may predict the teeth caries and the need for tooth extraction after the C-CRT. The primary endpoint was the link between the pre-C-CRT SII and the need for tooth extraction during the follow-up period.

RESULTS

A sum of 126 patients were included. Median follow-up was 4.9 years (range: 2.7-7.8). Nasopharyngeal and laryngeal cancers comprised the majority (75.4%) study cohort. Post-treatment teeth extractions were reported in 62.7% patients. The optimal cutoff was 558 [Area under the curve (AUC): %76.8 sensitivity: 72.3%; and specificity: 70.9%] that grouped the patients into two subgroups with significantly different post-C-CRT tooth extraction rates: Group 1: SII≤558 (n = 70) and SII>558 (n = 56), respectively. Correlation analysis revealed a significant relationship between the pretreatment SII and the tooth extraction rates after the C-CRT (rs:0.89: P = 0.001). The comparative analysis displayed that the teeth extractions rates were significantly higher in the SII>558 group (77.1% versus 51.4% for SII≤558; Hazard ratio: 1.68; P = 0.001). Further analyses showed that the pre-C-CRT SII>558 was the unique factor associated with meaningfully higher necessities for post-C-CRT teeth extractions.

CONCLUSION

The present outcomes intimated that high pretreatment SII levels were linked to significantly increased post-treatment teeth extractions in LA-SCHNC patients undergoing definitive C-CRT.

Performance of the 2017 AAP/EFP case definition compared to the CDC/AAP definition in population-based studies

BACKGROUND

Classification of the periodontal conditions is indispensable for epidemiological data in order to guide situational awareness and therapeutic strategies. The new classification of periodontal diseases and conditions introduced by the American Academy of Periodontology and the European Federation of Periodontology (AAP/EFP), however, has not yet been applied to population-based studies. The aim of the present study was to compare the prevalence of periodontitis between the AAP/EFP and the CDC/AAP classification system and to evaluate the accuracy of the new AAP/EFP classification system against the CDC/AAP case definition for population-based studies.

METHODS

Epidemiological data from two cross-sectional studies were obtained. One of them was a population-based study on Chilean adults (1.456 individuals; 35-44 years; 65-74 years) and the other one a sample of adolescents (1.070 individuals; 15-19 years) from 5 countries; Argentina, Chile, Colombia, Ecuador and Uruguay. All participants had undergone full-mouth periodontal examination by calibrated examiners. Epidemiological datasets were analyzed according to the AAP/EFP and the CDC/AAP case definitions. The accuracy of the AAP/EFP definition was examined by assessing the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and area under the receiver operating curve (ROC) using the CDC/AAP case definition as the reference standard.

RESULTS

According to the AAP/EFP, the prevalence of periodontitis in adolescents was 75.6%. The majority of the adolescents were classified either as stage I (39.2%) or stage II (28.2%). By using the CDC/AAP classification the prevalence of periodontitis in adolescents was 27.2%. The most common form of periodontitis with the CDC/AAP classification was moderate periodontitis (15.3%) followed by mild periodontitis (11.4%). The AAP/EFP revealed high sensitivity in moderate (95.7%) and severe periodontitis (100%) as well as a moderate (75%) to high specificity (92%) in moderate and severe periodontitis, respectively. The PPV was 41.6% in moderate and 5.7% in severe periodontitis while the NPV was high in both categories (moderate = 99%; severe = 100%). The AUC was 0.912 (95% CI = 0.89 - 0.93). In adults, the prevalence of periodontitis was 99% according to the AAP/EFP. The majority of adults were classified as stage IV (81.3%) whereas stage III amounted to 12.8%. By using the CDC/AAP classification, the prevalence of periodontitis in adults was 88.3% and the most common form of periodontitis was moderate periodontitis (57.2%) followed by severe periodontitis (29.7%). In adults, the AAP/EFP revealed high sensitivity in moderate (99.7%) and severe periodontitis (100%) but low specificity in both categories (moderate = 6.8%; severe = 8.3%). The PPV was 88.7% in moderate and 31.7% in severe periodontitis. The NPV was high in both categories (moderate = 76.5%; severe = 100%). The AUC was 0.573 (95% CI = 0.53 - 0.62).

CONCLUSIONS

This study revealed a clear discrepancy in the prevalence of periodontitis between the AAP/EFP and the CDC/AAP classification when using epidemiological data. The 2017 AAP/EFP classification system performs well compared to the CDC/AAP case definition in identifying adolescents with periodontitis. The AAP/EFP system seems less accurate in adults with high prevalence of periodontitis. This article is protected by copyright. All rights reserved.

Oral health and atherosclerotic cardiovascular disease: A review

Periodontal disease (PD) is common in the US and globally. Evidence suggests that poor oral health is associated with atherosclerotic cardiovascular disease (ASCVD); however, this relationship has not been a major focus in clinical cardiology. This manuscript will review the growing evidence linking PD to ASCVD, including pathophysiologic mechanisms and coexistent risk factors. Public health considerations with a focus on disparities, social determinants, preventive strategies, and a call to action to reduce the burden of coincident ASCVD and PD are also reviewed.

Serum Inflammatory and Prooxidant Marker Levels in Different Periodontal Disease Stages

BACKGROUND

Periodontitis has been associated to systemic diseases and this association could be due to an increase in circulating inflammatory and oxidative stress biomarkers in the periodontal disease. This study aimed to evaluate the relationship between inflammatory and pro-oxidant markers according to different stages of periodontitis.

METHODS

This cross-sectional study included 70 subjects who were divided into three groups according to periodontitis stage: stage II (n = 22), stage III (n = 30), and stage IV (n = 18). We evaluated periodontal parameters and levels of high-sensitivity C-reactive protein (hsCRP), fibrinogen, and malondialdehyde (MDA) in serum, and 8-hydroxy-2'-deoxyguanosine (8-OHdG) in urine.

RESULTS

Serum hsCRP and fibrinogen levels were associated with periodontitis severity, which were higher in stage IV than in stages III and II of periodontitis (p = 0.003 and p = 0.025, respectively). We observed a slight yet insignificant increase in MDA levels related to periodontitis severity. Probing depth and clinical attachment loss were associated with serum fibrinogen and hsCRP levels. However, there were no significant associations between periodontal variables and MDA and 8-OHdG levels.

CONCLUSION

Our data support an association between periodontitis and systemic inflammation, which increases with periodontal disease severity. This indicates the importance of the early diagnosis and treatment of periodontal disease to avoid the development or worsening of systemic inflammatory diseases.

Development of an immune-related lncRNA-miRNA-mRNA network based on competing endogenous RNA in periodontitis

AIM

To explore the relationship between long non-coding RNAs (lncRNAs) and immune response and to construct an immune-related competing endogenous RNA (ceRNA) network in periodontitis.

MATERIALS AND METHODS

Gene expression profiles in gingival tissues were acquired from the Gene Expression Omnibus database. Bioinformatic analysis was performed to establish an immune-related ceRNA network. Subsequently, functional enrichment analysis was performed to detect the biological processes in which the ceRNA network might be involved.

RESULTS

A combined classification model involving seven lncRNAs was constructed. Receiver operating characteristic curve analysis showed satisfactory classification ability of the established model. Further analysis revealed that the screened lncRNAs were significantly correlated with patient immunity. Finally, an immune-related ceRNA network was constructed based on the lncRNA MIAT, miR-1246, miR-1260b, miR-3652, miR-4286, and 27 mRNAs. Accordingly, functional enrichment analysis demonstrated that this network is closely related to the proliferation, differentiation, and activation of B cells.

CONCLUSIONS

The lncRNA MIAT and the MIAT-based ceRNA network may be instrumental in regulating the immune response, especially of B cells, during the progression of periodontitis.

Systemic inflammation and the relationship between periodontitis, edentulism, and all-cause mortality: A 17-year prospective cohort study

AIM

The aim was to investigate the role of systemic inflammation in the relationship between periodontitis, edentulism, and all-cause mortality in a group of men in Northern Ireland aged 58-72 years.

MATERIALS AND METHODS

A representative sample of 1558 men had a detailed dental examination between 2001 and 2003. The primary end point was death from any cause. Cox's proportional hazards model was used to assess the longitudinal relationship between periodontitis, edentulism, and all-cause mortality. Accelerated failure time modelling was performed to investigate the mediating role of systemic inflammation.

RESULTS

Mean age of the men at baseline was 64.3 (standard deviation 2.9) years. During a median follow-up of 17 years, 500 (32.1%) men died. After adjustment for confounding variables, compared to men with no/mild periodontitis, edentulous men had a hazard ratio for all-cause mortality of 1.52 (95% confidence interval [CI] 1.16-1.99) p < .01 and for those with severe periodontitis, it was 1.34 (95% CI 1.06-1.70) p = .01. Systemic inflammation accounted only for a minor mediating pathway effect of 10%.

CONCLUSIONS

There was evidence in this group of men that those who were edentulous or had severe periodontitis had a significantly increased risk of all-cause mortality. Systemic inflammation was not a major explanatory mediator of this association.

Are periodontal diseases associated with sleep duration or sleep quality? A systematic review

OBJECTIVES

This study aimed to systematically review the associations between periodontal diseases/tooth loss and sleep duration/quality.

MATERIAL AND METHODS

PubMed, Scopus, and Embase databases were searched (up to May 2021) to identify studies that assessed the association between periodontal diseases or number of teeth with sleep quality and sleep duration. Two researchers independently selected the studies and extracted the data. Considering the high heterogeneity among the included studies, meta-analysis was deemed unviable. Results are presented descriptively for sleep quality (studies that have used PSQI), self-reported sleep hours, and other tools that assessed sleep patterns.

RESULTS

Twenty studies (16 cross-sectional, two case-control, and two cohort) were included. Eight studies used the Pittsburgh Sleep Quality Index (PSQI) to assess quality of sleep. Six of these studies demonstrated that individuals with worse periodontal conditions demonstrated poorer sleep quality. However, most of the included studies that performed adjusted analysis showed no statistically significant association between self-reported hours of sleep and periodontitis. The mean number of present teeth was assessed in four studies; three of them demonstrated lower numbers of present teeth in individuals with inadequate sleep.

CONCLUSION

The literature shows conflicting results for the association between sleep hours and periodontitis. However, inadequate sleep may be associated with lower number of present teeth and periodontal diseases. Further studies are necessary in order to confirm these results.

Toothbrushing frequency and gastric and upper aerodigestive tract cancer risk: A meta-analysis

OBJECTIVE

Results of epidemiological studies evaluating the association between toothbrushing and gastric and upper aerodigestive tract (UADT) cancer risk showed inconsistent results. The purpose of this study was to evaluate the association between toothbrushing and gastric and UADT cancer risk and quantify the dose-response association between them.

METHODS

We searched the PubMed, EMBASE and Cochrane Library databases to identify relevant studies on toothbrushing and gastric and UADT cancer risk. Statistical analyses were performed using STATA 12.0 software.

RESULTS

A total of 30 studies of involving 1 194 017 participants met eligibility criteria and were included in the meta-analysis. Meta-analysis using a random-effect model showed that the high frequency of toothbrushing was associated with significantly reduced risk of gastric and UADT cancers (OR: 0.55, 95% CI 0.46-0.64, P < .05). Our dose-response analysis presented that every increased toothbrushing per day might reduce oral cavity cancer risk by 6%, pharyngeal cancer risk by 11%, laryngeal cancer risk by 3%, oesophageal cancer risk by 6% and gastric cancer risk by 4%.

CONCLUSIONS

This meta-analysis suggested the negative relationship between frequency of toothbrushing and risk of gastric and UADT cancers. Toothbrushing may be a protective factor for gastric and UADT cancers. However, this association must be further validated through large prospective studies.

Runs of homozygosity are associated with staging of periodontitis in isolated populations

Periodontitis is a common inflammatory disease characterized by a complex etiology, which is the result of a combination of genetic and environmental factors. Genetic variants linked to the periodontitis disease were already investigated, however, little was known regarding the severity of this disease. Recently, long runs of homozygosity (ROH) were associated with several multifactorial diseases. Therefore, in our work, we tried to assess the role of ROH and periodontitis status. We found an association between the excess of homozygosity owing to ROH and staging of periodontitis. More in detail, the total amount of homozygosity owing to ROH is positively associated with an increased severity of periodontitis (P = 0.0001). Regression tree analysis showed the impact of ROH burden in discriminating individuals with mild periodontitis stages I and II and periodontitis stages III and IV (P < 0.001). Furthermore, ROH mapping highlights several regions associated with a severe status of periodontitis (odds ratio > 1). Among them, we found a total of 33 genes. Interestingly, some of these genes were previously associated with granulocyte or platelet measures, both linked to the onset and the progression of periodontal disease. Our results suggest the not only single variants association test could help to risk assessment but even individual genomic features; furthermore, our ROH mapping highlighted the possible role of multiple genes in periodontal development.

Thermoresponsive Hydrogel-Based Local Delivery of Simvastatin for the Treatment of Periodontitis

Except for routine scaling and root planing, there are few effective nonsurgical therapeutic interventions for periodontitis and associated alveolar bone loss. Simvastatin (SIM), one of the 3-hydroxy-3-methylglutaryl-cosenzyme A reductase inhibitors, which is known for its capacity as a lipid-lowering medication, has been proven to be an effective anti-inflammatory and bone anabolic agent that has shown promising benefits in mitigating periodontal bone loss. The local delivery of SIM into the periodontal pocket, however, has been challenging due to SIM's poor water solubility and its lack of osteotropicity. To overcome these issues, we report a novel SIM formulation of a thermoresponsive, osteotropic, injectable hydrogel (PF127) based on pyrophosphorolated pluronic F127 (F127-PPi). After mixing F127-PPi with F127 at a 1:1 ratio, the resulting PF127 was used to dissolve free SIM to generate the SIM-loaded formulation. The thermoresponsive hydrogel's rheologic behavior, erosion and SIM release kinetics, osteotropic property, and biocompatibility were evaluated in vitro. The therapeutic efficacy of SIM-loaded PF127 hydrogel on periodontal bone preservation and inflammation resolution was validated in a ligature-induced periodontitis rat model. Given that SIM is already an approved medication for hyperlipidemia, the data presented here support the translational potential of the SIM-loaded PF127 hydrogel for better clinical management of periodontitis and associated pathologies.

The correlation between history of periodontitis according to staging and grading and the prevalence/severity of peri-implantitis in patients enrolled in maintenance therapy

BACKGROUND

The aim of this study was to determine if a previous history of periodontitis according to the preset definitions of the 2017 World Workshop is correlated with increased implant failure, and occurrence and severity of peri-implantitis (PI).

METHODS

A retrospective analysis of patients with a history of periodontitis who received nonsurgical and, if indicated, surgical corrective therapy prior to implant placement was performed. Periodontitis stage and grade were determined for each included patient based on data from the time of initiation of active periodontal therapy. Cox Proportional Hazard Frailty models were built to analyze the correlation between stage and grade of periodontitis at baseline with implant failure, as well as occurrence and severity of PI.

RESULTS

Ninety-nine patients with a history of periodontitis receiving 221 implants were followed for a mean duration of 10.6 ± 4.5 years after implant placement. Six implants (2.7%) failed and a higher rate of implant failure due to PI was found for grade C patients (P < 0.05), whereas only an increased trend was seen for stages III and IV compared with I and II. Grading significantly influenced the risk of marginal bone loss (MBL) >25% of the implant length (P = 0.022) in PI-affected implants. However, a direct correlation between higher-level stage and grade and PI prevalence was not recorded.

CONCLUSION

No statistically significant association between periodontitis stage or grade and the prevalence of PI was found. However, when PI was diagnosed, there was a relationship between periodontitis grade and severity of PI or the occurrence of implant failure.