Advances in the pathogenesis of periodontitis: summary of developments, clinical implications and future directions

The association between clinically determined periodontal disease and prostate-specific antigen concentration in men without prostate cancer: the 2009-2010 National Health and Nutrition Examination Survey

PURPOSE

We evaluated the association between clinically assessed periodontal disease and serum prostate-specific antigen (PSA) concentration in men without a prostate cancer diagnosis in a US nationally representative sample of non-institutionalized men.

METHODS

Included were 1263 men aged ≥ 40 years who participated in the National Health and Nutrition Examination Survey in 2009-2010. Measurements of periodontal health and tooth count were used to define periodontal disease severity (no, mild, moderate, severe) and edentulism. Linear and logistic regressions were used to estimate the association of periodontal disease severity and edentulism with PSA concentration and elevated PSA, respectively.

RESULTS

Adjusting for age and other factors including race, body mass index, and education, the natural logarithm of PSA concentration did not change with increasing severity (mild - 0.20, 95% confidence interval [CI] - 0.34 to - 0.05; moderate - 0.12, 95% CI - 0.26 to 0.01; severe - 0.16, 95% CI - 0.43 to 0.12; edentulism - 0.16, 95% CI - 0.35 to 0.04; P-trend 0.13) compared with dentate men without periodontal disease. Although the multivariable-adjusted ORs of elevated PSA were not statistically significant, participants with more severe periodontal disease were less likely to have PSA > 2.0 and > 2.5 ng/mL, but more likely to have PSA > 4.0 ng/mL, compared to dentate men without periodontal disease. Similar non-significant associations with PSA were observed when comparing edentulous men to dentate men without periodontal disease.

CONCLUSIONS

In this US nationally representative sample, men with periodontal disease did not have higher serum PSA and were not more likely to have clinically elevated PSA after taking into account age and other factors, contrary to the hypothesis. This study suggests that periodontal disease does not notably affect the specificity of PSA for prostate cancer screening.

Distribution of Periodontal Pockets Among Smokers and Nonsmokers in Patients with Chronic Periodontitis: A Cross-sectional Study

Context Cigarette smoking is a well-established risk factor for periodontitis and carries an increased risk for loss of periodontal attachment as well as bone loss. Aims The purpose of the present study was to investigate whether disease severity differs between smokers and nonsmokers in a group of chronic periodontitis patients by assessing the periodontal probing depth (PPD) and bleeding on probing (BOP). Materials and methods The study included 150 individuals, 75 smokers and 75 nonsmokers, in the age group of 35-60 years. Subjects with chronic periodontitis were selected and included in the study. Periodontal evaluation, including periodontal probing pocket depths and bleeding on probing, was performed on all four quadrants and at six sites per tooth using the Williams periodontal probe. The data were pooled from the anterior sextant and the posterior sextant as well as from the facial and lingual surfaces. Statistical analysis Comparisons were made between smokers and nonsmokers using the z-test (two-tailed test). Probing pocket depth categories 0-3 mm, 4-5 mm, 6-7 mm, and ≥8 mm and the proportion of sites having a pocket depth of ≥5 mm were used in the analysis. Results The mean percentage of sites that bleed upon probing was higher for nonsmokers as compared with smokers. Smokers had less shallow pockets (0-3 mm) than nonsmokers and more pockets of 4-7 mm (categories 4-5 mm, 6-7 mm). No significant differences were detected in the prevalence of pockets ≥8 mm. In the anterior, premolar, and molar regions, pockets of 6-7 mm were significantly more prevalent in smokers. The buccal and lingual sides also showed that smokers had more sites with deep probing depths ≥5 mm than nonsmokers. The data also showed that in the upper jaw, in the anterior and premolar teeth, the largest differences were found between smokers and nonsmokers. Conclusions From the results, it can be concluded that cigarette smoking results in periodontal tissue destruction in the different areas of the oral cavity, with the maximum periodontal destruction in the maxillary anterior and premolar region.

Periodontal disease: From the lenses of light microscopy to the specs of proteomics and next-generation sequencing

Periodontal disease entails the inflammatory destruction of the tooth supporting (periodontal) tissues as a result of polymicrobial colonization of the tooth surface in the form of biofilms. Extensive data collected over the past decades on this chronic disease demonstrate that its progression is infrequent and episodic, and the susceptibility to it can vary among individuals. Physical assessments of previously occurring damage to periodontal tissues remain the cornerstone of detection and diagnosis, whereas traditionally used diagnostic procedures do neither identify susceptible individuals nor distinguish between disease-active and disease-inactive periodontal sites. Thus, more sensitive and accurate "measurable biological indicators" of periodontal diseases are needed in order to place diagnosis (e.g., the presence or stage) and management of the disease on a more rational less empirical basis. Contemporary "omics" technologies may help unlock the path to this quest. High throughput nucleic acid sequencing technologies have enabled us to examine the taxonomic distribution of microbial communities in oral health and disease, whereas proteomic technologies allowed us to decipher the molecular state of the host in disease, as well as the interactive cross-talk of the host with the microbiome. The newly established field of metaproteomics has enabled the identification of the repertoire of proteins that oral microorganisms use to compete or co-operate with each other. Vast such data is derived from oral biological fluids, including gingival crevicular fluid and saliva, which is progressively completed and catalogued as the analytical technologies and bioinformatics tools progressively advance. This chapter covers the current "omics"-derived knowledge on the microbiome, the host and their "interactome" with regard to periodontal diseases, and addresses challenges and opportunities ahead.

Association between Periodontitis and Metabolic Syndrome in a Korean Nationally Representative Sample of Adults Aged 35-79 Years

This study aimed to evaluate the association between periodontitis and metabolic syndrome (MetS) and to investigate risk factors associated with MetS in Korean adults aged 35 to 79 years. Among individuals aged 35-79 years who participated in the Korea National Health and Nutrition Examination Survey 2013-2015, 8314 participants who completed the required examinations and questionnaires were included. Confounding variables related to demographic and socioeconomic status and systemic and oral health-related behaviors were age, gender, household income, education level, smoking, alcohol intake, physical activity, and frequency of daily toothbrushing. Of the 8314 participants, 32.2% were diagnosed with MetS. The prevalence of MetS was 26.6% and 41.6% in those without and with periodontitis, respectively. Among individuals with periodontitis, the prevalence of MetS was 44.3% in males and 36.9% in females. Compared to non-periodontitis, periodontitis was associated with MetS (adjusted OR = 1.422, 95% CI: 1.26-1.61). Age, frequency of daily toothbrushing, and periodontitis were associated with MetS in both males and females. While current smoking and alcohol intake more than twice a week were significantly associated with MetS in males, household income and education level were significantly associated with MetS in females. The findings suggest that periodontitis can be associated with MetS.

Epigenetic and inflammatory events in experimental periodontitis following systemic microbial challenge

AIM

The purpose of this study was to determine inflammatory and epigenetic features following induction of oral and gut dysbiosis in experimental periodontitis in order to examine the interplay between oral and systemic infection.

MATERIALS AND METHODS

Periodontitis was induced in 6- to 8-week-old C57BL/6 mice by (a) Ligature placement (Lig group) (oral challenge); (b) P. gingivalis gavage (Pg group) (systemic challenge); and (c) the combination of the two models oral and systemic challenge (Pg + Lig). The duration of the experiment was 60 days, and the animals were then sacrificed for analyses. Alveolar bone loss was assessed, and a multiplex immunoassay was performed. Maxillae and gut tissues were immunostained for DNMT3b (de novo methylation marker), B and T lymphocyte attenuator (BTLA) and IL-18R1 (inflammation markers).

RESULTS

Pg and Pg + Lig groups exhibited higher bone loss when compared to Sham. BAFF, VEGF, RANKL, RANTES and IP-10 were significantly higher with Pg gavage. Likewise, DNMT3b was overexpressed in both gut and maxilla after the Pg administration. The same pattern was observed for BTLA and IL-18R1 in gut tissues.

CONCLUSIONS

The systemic microbial challenge either alone or in combination with local challenge leads to distinct patterns of inflammatory and epigenetic features when compared to simply locally induced experimental periodontitis.

Development and validation of a self-management ability questionnaire for patients with chronic periodontitis

Objective

This study aimed to develop and validate a self-management ability questionnaire for patients with chronic periodontitis.

Methods

A questionnaire was developed through theoretical research, literature review, semi-structured interview, and expert consultation. A total of 231 patients with chronic periodontitis from the Department of Periodontics in the Stomatological Hospital of Tianjin Medical University were recruited by convenient sampling. Validity and reliability were analyzed.

Results

The questionnaire consisted of 24 items. Exploratory factor analysis identified three principal factors, which explained 66.949% of the total variance. The item-level content validity was between 0.800 and 1.000, and the scale-level content validity was 0.969. The coefficient of correlation between the gold standard and the whole questionnaire was 0.869. Cronbach's α of the whole questionnaire was 0.931, and the test–retest reliability coefficient was 0.825.

Conclusion

The questionnaire developed in this study satisfies the measurement standard and has good reliability and validity. It is useful for clinical work to measure self-management among patients with chronic periodontitis.

Application of cell-sheet engineering for new formation of cementum around dental implants

Periodontal disease involves the chronic inflammation of tooth supporting periodontal tissues. As the disease progresses, it manifests destruction of periodontal tissues and eventual tooth loss. The regeneration of lost periodontal tissue has been one of the most important subjects in periodontal research. Since their discovery, periodontal ligament stem cells (PDLSCs), have been transplanted into periodontal bony defects to examine their regenerative potential. Periodontal defects were successfully regenerated using PDLSC sheets, which were fabricated by cell sheet engineering in animal models, and for which clinical human trials are underway. To expand the utility of PDLSC sheet, we attempted to construct periodontal tissues around titanium implants with the goal of facilitating the prevention of peri-implantitis. In so doing, we found newly formed cementum-periodontal ligament (PDL) structures on the implant surface. In this mini review, we summarize the literature regarding cell-based periodontal regeneration using PDLSCs, as well as previous trials aimed at forming periodontal tissues around dental implants. Moreover, the recent findings in cementogenesis are reviewed from the perspective of the formation of further stable periodontal attachment structure on dental implant. This mini review aims to summarize the current status of the creation of novel periodontal tissue-bearing dental implants, and to consider its future direction.

Multiple chronic system diseases and periodontal pathology

Relevance: the prevalence and severity of chronic inflammatory periodontal diseases in multiple somatic diseases were assessed taking into account the gender and age of patients.

Materials and methods: a retrospective analysis of 841 "medical records of dental patients" of adult patients of both sexes aged 31 to 83 years who applied to dental clinics in Smolensk was carried out. Documented data on periodontal pathology and internal organs and systems diseases in patients were taken into account.

Results: it was established that the degree of severity of chronic inflammatory generalized periodontal disease in persons with somatic pathology is associated with the age of the patient, the duration and severity of the course of somatic diseases.

Conclusions: the result of the negative impact of somatic pathology on the periodontal condition is a violation of metabolic processes and tissue protection factors of the periodontal complex, which predisposes to the development of its lesion or accelerates the implementation of the existing periodontal factors.

Association between dental health and obstructive coronary artery disease: an observational study

Background

The association between dental health and coronary artery disease (CAD) remains a topic of debate. This study aimed to investigate the association between dental health and obstructive CAD using multiple dental indices.

Methods

Eighty-eight patients (mean age: 65 years, 86% male) were prospectively enrolled before undergoing coronary CT angiography (n = 52) or invasive coronary angiography (n = 36). Obstructive CAD was defined as luminal stenosis of ≥50% for the left main coronary artery or ≥ 70% for the other epicardial coronary arteries. All patients underwent thorough dental examinations to evaluate 7 dental health indices, including the sum of decayed and filled teeth, the ratio of no restoration, the community periodontal index of treatment needs, clinical attachment loss, the total dental index, the panoramic topography index, and number of lost teeth.

Results

Forty patients (45.4%) had obstructive CAD. Among the 7 dental health indices, only the number of lost teeth was significantly associated with obstructive CAD, with patients who had obstructive CAD having significantly more lost teeth than patients without obstructive CAD (13.08 ± 10.4 vs. 5.44 ± 5.74, p < 0.001). The number of lost teeth was correlated with the number of obstructed coronary arteries (p < 0.001). Multiple binary logistic regression analysis revealed that having ≥10 lost teeth was independently associated with the presence of obstructive CAD (odds ratio: 8.02, 95% confidence interval: 1.80–35.64; p = 0.006).

Conclusions

Tooth loss was associated with the presence of obstructive CAD in patients undergoing coronary evaluation. Larger longitudinal studies are needed to determine whether there is a causal relationship between tooth loss and CAD.

Periodontal tissue destruction in aggressive periodontitis: Determination of gene or environmental factors

Aim

This study observed the role of defective neutrophil function in aggressive periodontitis through FPR1 gene polymorphism and the level of Il-8 compared with the role of dental plaque presence towards periodontal tissue damage (Clinical Attachment Loss/CAL) in patients in Indonesia.

Methods

Case-control study was used to detect differences in polymorphism expression of FPR1 gene, the level of Il-8, dental plaque, and Clinical Attachment Loss/CAL from 32 Aggressive Periodontitis (AP) and 29 Non-Aggressive Periodontitis (NAP) samples, selected with consecutive sampling method. Polymorphism was identified using polymerase chain reaction (PCR) technique, and the level of IL-8 in the gingival crevicular fluid was identified using the enzyme-linked immunosorbent assay (ELISA) test. The Clinical Attachment Loss was analysed by using William periodontal probe, and the oral environment analysis was performed by using the OHI-S plaque index. Statistical analysis was used to determine the significance of the polymorphism difference of FPR gene, Il-8, Plaque and CAL amongst all subjects and also the control and correlations among these factors.

Results

The results showed that in the Aggressive Periodontitis (AP), the presence of the polymorphism of c576 T > C > G of FPR1 gene caused as much as 5.04 times higher occurrence of aggressive periodontitis (p = 0.006; OR = 5.040 (1.51–16.74)). The low level of Il-8 (below 0.064 pg/μl), showed as much as 34.5 times higher occurrence of aggressive periodontitis (OR = 34.5 (6.76–176.08)). The oral hygiene of the AP samples were better significantly (p = 0.002), and on the Clinical Attachment Loss (CAL) sample was even more (p = 0.02). The polymorphism of c301 G > C of FPR1 gene correlated with the CAL (r = 0.37; p = 0.039). The polymorphism of c576 T > C > G correlated significantly with the Il-8 (r = 0.5; p = 0.0287). The polymorphism of c348 T > C correlated significantly with the dental plaque (r = 0.355; p = 0.049), whereas the dental plaque correlation with CAL was not significant.

Conclusion

The research conclusion showed that in aggressive periodontitis, genetic and environmental factors were correlated with the cause of periodontal tissue injury, and the role of genetic factors was more prominent on the injury.

Spontaneous differentiation of periodontal ligament stem cells into myofibroblast during ex vivo expansion

Periodontitis is characterized by the chronic inflammation and destruction of tooth-supporting tissues. Periodontal ligament stem cell (PDLSC) is the mesenchymal stem cell (MSC) population isolated from periodontal ligament, which is the key tissue for regeneration of periodontal tissues. Although transplantation of PDLSCs is proposed as novel regenerative therapy, limited information is available, regarding the characteristic change of PDLSCs during ex vivo expansion. In this study, we encountered morphological change of PDLSCs during standard cell culture and aimed to investigate the change of PDLSCs in stem cell characteristics and to search for the culture condition to maintain stem cell properties. Characteristics of PDLSCs were examined using in vitro osteoblast and adipocyte differentiation. Myofibroblast differentiation was confirmed using immunohistochemistry and collagen gel contraction assay. Replicative senescence was examined by β-gal staining. PDLSCs changed their morphology from spindle to flat and wide during ex vivo expansion. After the morphological change, PDLSCs showed several features of myofibroblast including extensive stress fiber formation, contraction activity, and myofibroblast marker expression. Upon the morphological change, osteoblastic and adipocyte differentiation capacity were reduced and expression of stem cell-related genes were decreased. β-Gal staining was not always correlated with the morphological change of PDLSCs. Moreover, exogenous addition of bFGF and PDGF-BB served to maintain spindle shape and osteoblastic differentiation potential of PDLSCs. This study demonstrates that spontaneous differentiation of PDLSCs during ex vivo expansion and may provide the important information of cell culture condition of PDLSCs for clinical use.

Periodontal complications with obesity

The purpose of this paper was to identify and summarize current evidence describing periodontal complications associated with obesity. Electronic searches supplemented with manual searches were carried out to identify relevant systematic reviews. Identification, screening, eligibility, and inclusion of studies were performed independently by two reviewers. A MeaSurement Tool to Assess systematic Reviews (AMSTAR) was used to assess the quality and risk of bias of the included reviews. From 430 titles and abstracts screened, 14 systematic reviews were considered as eligible for inclusion in this meta-review. Eight reviews reported on cross-sectional studies investigating the association of obesity and periodontal diseases, 4 included longitudinal studies, 5 addressed response to periodontal therapy, 5 reported on studies investigating biomarkers, and only 2 were related to pediatric population samples. Systematic review summaries in the various study design domains (cross-sectional, longitudinal and experimental) report that obese individuals are more likely to have periodontal diseases, with more severe periodontal conditions, than nonobese individuals, with cross-sectional evidence congruent with longitudinal studies showing that obesity or weight gain increases the risk of periodontitis onset and progression. Published research on the effect of obesity on responses to periodontal therapy, or systemic or local biomarkers of inflammation, is variable and therefore inconclusive based on the evidence currently available, which suggests that overweight/obesity contributes to periodontal complications independently of other risk factors, such as age, gender, smoking, or ethnicity. This evidence supports the need for risk assessments for individual patients to facilitate personalized approaches in order to prevent and treat periodontal diseases.

Periodontal health: A national cross-sectional study of knowledge, attitudes and practices for the public oral health strategy in China

AIM

To assess the status of periodontal health knowledge, attitudes and practices (KAP) among Chinese adults.

MATERIALS AND METHODS

A cross-sectional study was conducted in a nationally representative sample of adults (N = 50,991) aged 20 years or older from ten provinces, autonomous regions, and municipalities. Percentages of Chinese adults with correct periodontal knowledge, positive periodontal attitudes, and practices were estimated. Multiple logistic regression analyses were used to examine the related factors.

RESULTS

Less than 20% of Chinese adults were knowledgeable about periodontal disease. Very few (2.6%) of Chinese adults use dental floss ≥once a day and undergo scaling ≥once a year and visit a dentist (6.4%) in the case of gingival bleeding. Periodontal health KAP was associated with gender, age, body mass index, marital status, place of residence, education level, income, smoking status, and history of periodontal disease.

CONCLUSIONS

Periodontal health KAP are generally poor among the Chinese adult population. Community-based health strategies to improve periodontal health KAP need to be implemented. Increasing knowledge of periodontal disease, the cultivation of correct practices in response to gingival bleeding, and the development of good habits concerning the use of dental floss and regular scaling should be public oral health priorities.

Zoledronate treatment duration is linked to bisphosphonate-related osteonecrosis of the jaw prevalence in rice rats with generalized periodontitis

OBJECTIVES

To determine the extent that zoledronate (ZOL) dose and duration is associated with bisphosphonate-related osteonecrosis of the jaw (BRONJ) prevalence in rice rats with generalized periodontitis (PD), characterize structural and tissue-level features of BRONJ-like lesions in this model, and examine the specific anti-resorptive role of ZOL in BRONJ.

MATERIALS AND METHODS

Rice rats (n = 228) consumed high sucrose-casein diet to enhance generalized PD. Groups of rats received 0, 8, 20, 50 or 125 µg/kg IV ZOL/4 weeks encompassing osteoporosis and oncology ZOL doses. Rats from each dose group (n = 9-16) were necropsied after 12, 18, 24 and 30 weeks of treatment. BRONJ-like lesion prevalence and tissue-level features were assessed grossly, histopathologically and by MicroCT. ZOL bone turnover effects were assessed by femoral peripheral quantitative computed tomography, serum bone turnover marker ELISAs and osteoclast immunolabelling.

RESULTS

Prevalence of BRONJ-like lesions was significantly associated with (a) ZOL treatment duration, but plateaued at the lowest oncologic dose, and (b) there was a similar dose-related plateau in the systemic anti-resorptive effect of ZOL. ZOL and BRONJ-like lesions also altered the structural and tissue-level features of the jaw.

CONCLUSION

The relationship between BRONJ-like lesion prevalence and ZOL dose and duration varies depending on the co- or pre-existing oral risk factor. At clinically relevant doses of ZOL, BRONJ-like lesions are associated with anti-resorptive activity.

Comparison of effectiveness of low-dose aspirin versus omega-3 fatty acids as adjuvants to nonsurgical periodontal therapy in Type II diabetic patients with chronic periodontitis

Context:

Periodontitis and diabetes are universally prevalent diseases which are interlinked with each other. Inflammatory products released both by the microorganisms, and the host plays a pivotal role in causing both the diseases. Pentraxins are acute-phase proteins which are often found to be elevated in inflammatory states. Anti-inflammatory agents have a very important role to play in curbing infection of which, aspirin and omega-3 fatty acids (O3FAs) are being administered often nowadays. Nonsurgical periodontal therapy (NSPT) remains the gold standard of treatment, and other agents have been used as adjuvants only, to increase the efficacy of treatment.

Aims:

This study compares the effects of low-dose aspirin versus O3FAs when used as adjuvants to NSPT in patients with diabetes and chronic periodontitis.

Settings and Design:

A total of 42 patients (mean age of 30–65 years) from a diabetic center who were diagnosed with Type II diabetes and chronic periodontitis were included in the study.

Materials and Methods:

This study was done in the department of periodontics of a tertiary referral care hospital in Hyderabad, in collaboration with a reputed diabetic center.

Statistical Analysis Used:

Intragroup comparison was done using the paired t-test for continuous data and Wilcoxon signed-rank test for score data. Intergroup comparison was compiled using independent t-test. All P < 0.05 were considered statistically significant.

Results:

Intragroup comparison at baseline and 3 months after NSPT showed statistically significant results (P < 0.001) in all the three groups pertaining to the clinical (gingival index, probing pocket depth, and clinical attachment level) and biochemical (glycosylated hemoglobin and pentraxin) parameters. However, the intergroup comparison showed a significant improvement in Group II related to pentraxin levels only (P < 0.001).

Conclusions:

O3FAs proved to be better than low-dose aspirin and placebo after NSPT.

[Periodontal disease: epidemiological approaches for its analysis as a public health concern]

The way how health problems are defined allow conceptual and methodological developments that lead to different outcomes and specific analytical and preventive approaches to confront problems. This essay aims to show some of the main epidemiological approaches that have been used to address the oral health-disease process, in particular the periodontal disease. Regarding the latter, different approaches to their understanding are proposed, which have been influenced by the biological-curative model, whose scope is limited and focused on the identification of risk factors and on demonstrating causal relationships. However, more comprehensive alternatives are also portrayed from social epidemiology that include social determinants in the analysis of the health-disease process, which affects and influences this process in the communities.

A noninvasive imaging and measurement using optical coherence tomography angiography for the assessment of gingiva: An in vivo study

Gingiva is the soft tissue that surrounds and protects the teeth. Healthy gingiva provides an effective barrier to periodontal insults to deeper tissue, thus is an important indicator to a patient's periodontal health. Current methods in assessing gingival tissue health, including visual observation and physical examination with probing on the gingiva, are qualitative and subjective. They may become cumbersome when more complex cases are involved, such as variations in gingival biotypes where feature and thickness of the gingiva are considered. A noninvasive imaging technique providing depth-resolved structural and vascular information is necessary for an improved assessment of gingival tissue and more accurate diagnosis of periodontal status. We propose a three-dimensional (3D) imaging technique, optical coherence tomography (OCT), to perform in situ imaging on human gingiva. Ten volunteers (five male, five female, age 25-35) were recruited; and the labial gingival tissues of upper incisors were scanned using the combined use of state-of-the-art swept-source OCT and OCT angiography (OCTA). Information was collected describing the 3D tissue microstructure and capillary vasculature of the gingiva within a penetration depth of up to 2 mm. Results indicate significant structural and vascular differences between the two extreme gingival biotypes (ie, thick and thin gingiva), and demonstrate special features of vascular arrangement and characteristics in gingival inflammation. Within the limit of this study, the OCT/OCTA technique is feasible in quantifying different attributes of gingival biotypes and the severity of gingival inflammation.

The effect of green tea as an adjunct to scaling and root planing in non-surgical periodontitis therapy: a systematic review

OBJECTIVE

To provide a systematic overview on the efficacy of green tea catechin as an adjunct to scaling and root planing (SRP) in terms of probing pocket depth (PPD).

MATERIALS AND METHODS

A systematic literature search was performed using electronic databases in PubMed, Scopus, Medline, Cochrane, CINAHL, and Web of Science on randomized clinical trials up to January 2017. The research question was posed in accordance with PRISMA guidelines.

RESULTS

The search provided 234 studies. After analyzing the full texts, five studies were included, with four studies qualifying for meta-analysis. Mean PPD reduction was significantly higher (α = 0.05) when green tea catechin was used as an adjunct to SRP (test group) than with SRP alone (control group). The difference in the reduction was 0.74 mm [0.35-1.13; 95% CI].

CONCLUSION

The local application of green tea catechin as an adjunct to SRP may result in a beneficial reduction in PPD. Due to the highly heterogeneous data and some risk of bias, however, this data still needs to be interpreted with caution.

CLINICAL RELEVANCE

The finding suggests that green tea catechin may be a topical adjunct to SRP without negative side effects.

Vitamin D deficiency in patients with aggressive periodontitis

OBJECTIVES

Vitamin D deficiency is a frequent health problem worldwide, especially as fewer people spend much time in the sun. Vitamin D deficiency is linked to several infectious and inflammatory conditions, including periodontal disease. However, its role in aggressive periodontitis (AgP) has not been well studied. We evaluated the association between vitamin D concentration and periodontal disease, both AgP and chronic (CP) periodontitis.

METHOD AND MATERIALS

Forty-seven AgP 55 CP and 27 control subjects participated. All patients were tested for serum vitamin D concentration (25(OH)D), parathyroid hormone, and serum bone-related biomarkers (alkaline phosphatases, calcium, and phosphorus) regulated by vitamin D.

RESULTS

The patients with AgP had lower serum 25(OH)D concentration (11.22 ± 4.8 ng/ml) than controls (16.9 ± 6.4 ng/ml) and patients with CP (16.13 ± 8.3 ng/ml; overall p value 0.0002). These associations remained significant after adjustment for age and gender (p = 0.002). No significant differences were observed in any bone-related biomarker among the three groups, and no association was observed with periodontal disease indices.

CONCLUSIONS

Our results suggest that vitamin D deficiency may be a potential risk factor for AgP. Given the high prevalence of vitamin D deficiency in AgP patients, routine screening for vitamin D status may be advisable in these subjects.

Oral Microbes, Biofilms and Their Role in Periodontal and Peri-Implant Diseases

Despite many discoveries over the past 20 years regarding the etio-pathogenesis of periodontal and peri-implant diseases, as well as significant advances in our understanding of microbial biofilms, the incidence of these pathologies still continues to rise. This review presents a general overview of the main protagonists and phenomena involved in oral health and disease. A special emphasis on the role of certain keystone pathogens in periodontitis and peri-implantitis is underlined. Their capacity to bring a dysregulation of the homeostasis with their host and the microbial biofilm lifestyle are also discussed. Finally, the current treatment principles of periodontitis and peri-implantitis are presented and their limits exposed. This leads to realize that new strategies must be developed and studied to overcome the shortcomings of existing approaches.

Effect of total sonicated Aggregatibacter actinomycetemcomitans fragments on gingival stem/progenitor cells

Background

Aggregatibacter-actinomycetemcomitans (A.actinomycetemcomitans) are strongly associated with localized-aggressive-periodontitis (LAgP). The study’s aim was to test for the first time the effect of total sonicated A.actinomycetemcomitans-bacterial-fragments on gingival mesenchymal stem/progenitor cells’ (G-MSCs) proliferation and regenerative gene expression in-vitro.

Material and Methods

G-MSCs were isolated, characterized, expanded and stimulated by total sonicated A.actinomycetemcomitans-bacterial-fragments (0 (negative-control), 15, 60, 120 and 240µg/ml; serovar-b; n=6/group). Cellular proliferation and NF-κβ (NFKB1), Alkaline Phosphatase (ALPL), Collagen-I (COL1A1), Collagen-III (COL3A1), Osteonectin (SPARC) and Osteopontin (SPP1) m-RNA expression were assessed via reverse-transcription-polymerase-chain-reaction (RT-PCR) at 24, 48 and 72 hours and CFUs-ability evaluated at twelve days.

Results

G-MSCs demonstrated stem/progenitor cells’ characteristics. A.actinomycetemcomitans-bacterial-fragments (up to 72 hours) resulted in marked G-MSCs’ proliferation over-time (p<0.001) and elevated NFKB1 (p=0.017), COL1A1 (p=0.025), SPARC (p=0.025), decreased ALPL (p=0.017), with no significant differences for COL3A1 and SPP1 expression or stimulation times (p>0.05; Friedman-test). Longer-term stimulation for twelve days reduced G-MSCs’ CFUs.

Conclusions

Sonicated A.actinomycetemcomitans-bacterial-fragments’ exert beneficial short-term effects on G-MSCs’ proliferative and non-mineralized tissue forming aptitude. Results shed new light on the importance of periodontal treatment for LAgP patients, using power driven sonic/ultrasonic devices, which, in addition to reducing the subgingival microbial load, produces cell-stimulatory A.actinomycetemcomitans-bacterial-fragments, with positive attributes on tissue reparative/regenerative responses of tissue resident stem/progenitor cells in their niche.

Key words:Ultrasonic, Aggregatibacter actinomycetemcomitans, stem cells, gingiva, Aggressive periodontitis.

Allergic rhinitis and periodontitis among Korean adults: results from a nationwide population-based study (2013-2015)

BACKGROUND

The purpose of this study was to examine whether allergic rhinitis is associated with periodontal disease in a representative sample of elderly Korean people that was adjusted for socio-demographic factors, oral and general health behaviors, and systemic health status.

METHODS

A total of 10,643 subjects who were between 20 and 59 years of age participated in the Korean National Health and Nutrition Examination Survey and underwent cross-sectional examination. Medical history of allergic rhinitis was collected from participants by questionnaire; additionally, periodontal status was assessed using a Community Periodontal Index score of 3 or 4. Multivariate logistic regression analysis was conducted to adjust for socio-demographic variables, oral health status and behaviors, and general health status and behaviors. All analyses were performed using a complex sampling design.

RESULTS

Allergic rhinitis and periodontitis showed a significant inverse association. After adjusting for all confounders, a trend of decreasing periodontitis risk was observed as allergic rhinitis increased. The adjusted odds ratio of periodontitis was 0.79 (0.66-0.95) for patients with allergic rhinitis.

CONCLUSION

A significant inverse association between allergic rhinitis and periodontal status was demonstrated in this patient population.

Effect of orthodontic force associated with cigarette smoke inhalation in healthy and diseased periodontium. A histometric and immunohistochemistry analysis in rats

BACKGROUND

The aim of the present study is to evaluate the effect of orthodontic forces in healthy or diseased periodontium of rats submitted/not submitted to cigarette smoke inhalation.

MATERIAL AND METHODS

Fifty-six male Wistar rats were allocated into two groups of conditions: smoking and non-smoking. Each group was divided into the following subgroups: control (C), orthodontic tooth movement (OTM), ligature-induced periodontitis (P) and P+OTM (POTM), with n = 14 each. Periodontitis was induced in the lower first molar by cotton ligature, and a 4 mm closed stainless steel spring was used for orthodontic movement. Animals were exposed to the smoke of 10 cigarettes for 8 minutes, 3 times a day for 60 days before P induction and OTM. Evaluation parameters were macroscopic analysis of dental movement, bone loss and bone density. In addition, the receptor activator of nuclear factor-kappaB (RANK) immunostaining and RANK ligand/osteoprotegerin ratio in the furcation region were assessed.

RESULTS

There was no statistically significant difference between groups, ie, smoking and non-smoking conditions (P = .338). Bone loss intragroup analysis between the P and POTM groups was not significant in smoking (P = 1) and non-smoking (P = .5) conditions; both were different from OTM and C in each condition. Regarding bone density, POTM and P were significant to C (P < .05). The POTM group was significant to the P and C (P = .001) regarding dental movement. The RANK ligand/osteoprotegerin ratio in the non-smoking condition was higher in P and POTM compared to C and OTM and to P and POTM in the smoking condition. RANK immunostaining was significant in the smoking condition for the P and POTM groups (P < .05).

CONCLUSION

Within the limitations of the present study, it was concluded that cigarette smoke inhalation had no influence on the evaluated groups, even with the presence of low levels of nicotine, carbon monoxide and tar. The POTM groups did not present greater bone loss compared to P groups, thus periodontal disease is essential for bone loss.

Defining the gut microbiota in individuals with periodontal diseases: an exploratory study

Background: This exploratory study aimed to characterize the gut microbiome of individuals with different periodontal conditions, and correlate it with periodontal inflammation and tissue destruction. Methods: Stool samples were obtained from individuals presenting periodontal health (PH = 7), gingivitis (G = 14) and chronic periodontitis (CP = 23). The intestinal microbiome composition was determined by Illumina MiSeq sequencing. Results: A lower alpha-diversity in the gut microbiome of individuals with CP was observed, although no significant difference among groups was found (p > 0.01). Firmicutes, Proteobacteria, Verrucomicrobia and Euryarchaeota were increased, whereas Bacteroidetes were decreased in abundance in patients with periodontitis compared to PH. Prevotella (genus), Comamonadaceae (family) and Lactobacillales (order) were detected in higher numbers in G, while Bacteroidales (order) was predominant in PH (p < 0.01). Significant correlations (rho = 0.337-0.468, p < 0.01) were found between OTUs representative of periodontal pathogens and attachment loss. Mogibacteriaceae, Ruminococcaceae and Prevotella were able to discriminate individuals with periodontal diseases from PH (overall accuracy = 84%). Oral taxa were detected in high numbers in all stool samples. Conclusions: Individuals with periodontal diseases present a less diverse gut microbiome consistent with other systemic inflammatory diseases. High numbers of oral taxa related to periodontal destruction and inflammation were detected in the gut microbiome of individuals regardless of periodontal status.

The effect of dietary corn oil and fish oil supplementation in dogs with naturally occurring gingivitis

The aim of this randomized, double-blinded, placebo-controlled study was to evaluate if downregulation of the inflammatory response due to ingestion of high levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) can slow down gingivitis development, and thus delay the progression of periodontal disease (PD) in dogs. To this aim, 44 client-owned adult dogs (>1 and <8 years old) with naturally occurring PD (stages 1 and 2) were submitted to a plaque, gingivitis and calculus scoring followed by a dental cleaning procedure and collection of blood samples. The animals were then fed a canine adult maintenance diet, supplemented with either corn oil (0.00 g EPA and 0.00 g DHA) or fish oil (1.53 g EPA and 0.86 g DHA, both per 1,000 kcal ME) over the following 5 months. At the end of this period, the PD scoring and the blood sampling were repeated. The animals consuming fish oil had higher plasma levels of the longer chain (C ≥ 20) omega 3 fatty acids (p < 0.01) and similar plasma levels of alpha-linolenic acid (p = 0.53), omega 6 fatty acids (p > 0.63) and C reactive protein (p = 0.28) then the ones consuming corn oil. There were no differences between fish oil and corn oil diet supplementation on plaque (18.2 vs. 17.8, p = 0.78), calculus (10.1 vs. 11.5, p = 0.18) or gingivitis (19.3 vs. 19.0, p = 0.77) indexes. The authors conclude that supplementation with EPA + DHA does not slow down progression of PD in dogs.

Revisiting the Page & Schroeder model: the good, the bad and the unknowns in the periodontal host response 40 years later

In their classic 1976 paper, Page & Schroeder described the histopathologic events and the types of myeloid cells and lymphocytes involved in the initiation and progression of inflammatory periodontal disease. The staging of periodontal disease pathogenesis as 'initial', 'early', 'established' and 'advanced' lesions productively guided subsequent research in the field and remains fundamentally valid. However, major advances regarding the cellular and molecular mechanisms underlying the induction, regulation and effector functions of immune and inflammatory responses necessitate a reassessment of their work and its integration with emerging new concepts. We now know that each type of leukocyte is actually represented by functionally distinct subsets with different, or even conflicting, roles in immunity and inflammation. Unexpectedly, neutrophils, traditionally regarded as merely antimicrobial effectors in acute conditions and protagonists of the 'initial' lesion, are currently appreciated for their functional versatility and critical roles in chronic inflammation. Moreover, an entirely new field of study, osteoimmunology, has emerged and sheds light on the impact of immunoinflammatory events on the skeletal system. These developments and the molecular dissection of crosstalk interactions between innate and adaptive leukocytes, as well as between the immune system and local homeostatic mechanisms, offer a more nuanced understanding of the host response in periodontitis, with profound implications for treatment. At the same time, deeper insights have generated new questions, many of which remain unanswered. In this review, 40 years after Page & Schroeder proposed their model, we summarize enduring and emerging advances in periodontal disease pathogenesis.

IL-6 and TNF-α salivary levels according to the periodontal status in Portuguese pregnant women

Background

Periodontitis is associated with increased concentration of inflammatory markers and saliva has been proposed as a non-invasive diagnostic fluid in oral and systemic diseases. The levels of salivary biomarkers, such as cytokines, could potentially be used to distinguish periodontal healthy individuals from subjects with periodontal disease. The purpose of this study was to characterize the salivary levels of two inflammatory biomarkers associated with periodontitis, interleukin-6 (IL-6) and tumour necrosis factor-alpha (TNF-α), in order to assess whether these cytokines salivary levels could potentially be used to complement periodontitis pregnant women diagnose.

Methods

Forty-four pregnant women were distributed into three groups, according to their periodontal status: healthy, mild/moderate periodontitis and severe periodontitis. Unstimulated saliva was collected and analysis of TNF-α and IL-6 salivary levels were performed with Immulite^®.

Results

Women with periodontitis exhibited significantly higher levels (p = 0.001) of salivary IL-6 and TNF-α compared with the healthy group: 25.1 (±11.2) pg/mL vs. 16.3 (±5.0) pg/mL and 29.7 (±17.2) pg/mL vs. 16.2 (±7.6) pg/mL, approximately 1.5 and 1.8 times more, respectively. Additionally, cytokines were significantly increased (p < 0.05) in severe periodontitis compared to periodontal healthy pregnant women.

Conclusions

These results revealed that IL-6 and TNF-α salivary biomarkers provide high discriminatory capacity for distinguishing periodontal disease from periodontal health in pregnant women.

Potential role of periodontal pathogens in compromising epithelial barrier function by inducing epithelial-mesenchymal transition

BACKGROUND AND OBJECTIVE

Epithelial-mesenchymal transition (EMT) is a process by which epithelial cells acquire a mesenchymal-like phenotype and this may be induced by exposure to gram-negative bacteria. It has been proposed that EMT is responsible for compromising epithelial barrier function in the pathogenesis of several diseases. However, the possible role of EMT in the pathogenesis of periodontitis has not previously been investigated. The aim of this study therefore was to investigate whether gram-negative, anaerobic periodontal pathogens could trigger EMT in primary oral keratinocytes in vitro.

MATERIAL AND METHODS

Primary oral keratinocytes were harvested from labial mandibular mucosa of Wistar Han rats. Cells were exposed to heat-killed Fusobacterium nucleatum and Porphyromonas gingivalis (100 bacteria/epithelial cell) and to 20 μg/mL of Escherichia coli lipopolysaccharide over an 8-day period. Exposure to bacteria did not significantly change epithelial cell number or vitality in comparison with unstimulated controls at the majority of time-points examined. Expression of EMT marker genes was determined by semiquantitative RT-PCR at 1, 5, and 8 days following stimulation. The expression of EMT markers was also assessed by immunofluorescence (E-cadherin and vimentin) and using immunocytochemistry to determine Snail activation. The loss of epithelial monolayer coherence, in response to bacterial challenge, was determined by measuring trans-epithelial electrical resistance. The induction of a migratory phenotype was investigated using scratch-wound and transwell migration assays.

RESULTS

Exposure of primary epithelial cell cultures to periodontal pathogens was associated with a significant decrease in transcription (~3-fold) of E-cadherin and the upregulation of N-cadherin, vimentin, Snail, matrix metalloproteinase-2 (~3-5 fold) and toll-like receptor 4. Bacterial stimulation (for 8 days) also resulted in an increased percentage of vimentin-positive cells (an increase of 20% after stimulation with P. gingivalis and an increase of 30% after stimulation with F. nucleatum, compared with controls). Furthermore, periodontal pathogens significantly increased the activation of Snail (60%) and cultures exhibited a decrease in electrical impedance (P < .001) in comparison with unexposed controls. The migratory ability of the cells increased significantly in response to bacterial stimulation, as shown by both the number of migrated cells and scratch-wound closure rates.

CONCLUSION

Prolonged exposure of primary rat oral keratinocyte cultures to periodontal pathogens generated EMT-like features, which introduces the possibility that this process may be involved in loss of epithelial integrity during periodontitis.

Gingival crevicular fluid levels of human beta-defensin 1 in individuals with and without chronic periodontitis

BACKGROUND AND OBJECTIVE

Human beta-defensins (hBDs) contribute to innate immunity antimicrobial activity. They are also effective in the adaptive immune response and may play a crucial role in the susceptibility to diseases of the oral cavity. This study aimed to evaluate the levels of hBD-1 in the gingival crevicular fluid of individuals with and without chronic periodontitis.

MATERIAL AND METHODS

Twenty periodontally healthy individuals (H) and 20 individuals with chronic periodontitis were recruited. Gingival crevicular fluid samples were collected from: healthy sites (Hh) from periodontally healthy individuals; and healthy sites (Ph), sites with gingivitis (Pg), and sites with periodontitis (Pp) from individuals with periodontitis. The levels of hBD-1 (pg/mL) were measured using enzyme-linked immunosorbent assay. Comparisons of hBD-1 between individuals (H and chronic periodontitis) and among sites (Hh, Ph, Pg, Pp) were performed through hierarchical linear modeling.

RESULTS

Gingival crevicular fluid levels of hBD-1 were: Hh = 229.52 ± 138.96 (median 199.26), Ph = 53.88 ± 58.17 (median 35.75), Pg = 57.11 ± 40.18 (median 39.90) and Pp = 55.31 ± 37.28 (median 54.19). No influence of site diagnosis (level 1; health/gingivitis/periodontitis) was observed; however, individual diagnosis (level 2; health/periodontitis) influenced the levels of hBD-1 (P < .001).

CONCLUSION

Periodontally healthy individuals showed higher gingival crevicular fluid levels of hBD-1 when compared to individuals with chronic periodontitis. This suggests a potential protective role of hBD-1 in the susceptibility to chronic periodontitis.

Linkage of Infection to Adverse Systemic Complications: Periodontal Disease, Toll-Like Receptors, and Other Pattern Recognition Systems

Toll-like receptors (TLRs) are a group of pattern recognition receptors (PRRs) that provide innate immune sensing of conserved pathogen-associated molecular patterns (PAMPs) to engage early immune recognition of bacteria, viruses, and protozoa. Furthermore, TLRs provide a conduit for initiation of non-infectious inflammation following the sensing of danger-associated molecular patterns (DAMPs) generated as a consequence of cellular injury. Due to their essential role as DAMP and PAMP sensors, TLR signaling also contributes importantly to several systemic diseases including cardiovascular disease, diabetes, and others. The overlapping participation of TLRs in the control of infection, and pathogenesis of systemic diseases, has served as a starting point for research delving into the poorly defined area of infection leading to increased risk of various systemic diseases. Although conflicting studies exist, cardiovascular disease, diabetes, cancer, rheumatoid arthritis, and obesity/metabolic dysfunction have been associated with differing degrees of strength to infectious diseases. Here we will discuss elements of these connections focusing on the contributions of TLR signaling as a consequence of bacterial exposure in the context of the oral infections leading to periodontal disease, and associations with metabolic diseases including atherosclerosis and type 2 diabetes.

Surgery without papilla incision: tunneling flap procedures in plastic periodontal and implant surgery

Diverse clinical advancements, together with some relevant technical innovations, have led to an increase in popularity of tunneling flap procedures in plastic periodontal and implant surgery in the recent past. This trend is further promoted by the fact that these techniques have lately been introduced to a considerably expanded range of indications. While originally described for the treatment of gingival recession-type defects, tunneling flap procedures may now be applied successfully in a variety of clinical situations in which augmentation of the soft tissues is indicated in the esthetic zone. Potential clinical scenarios include surgical thickening of thin buccal gingiva or peri-implant mucosa, alveolar ridge/socket preservation and implant second-stage surgery, as well as soft-tissue ridge augmentation or pontic site development. In this way, tunneling flap procedures developed from a technique, originally merely intended for surgical root coverage, into a capacious surgical conception in plastic periodontal and implant surgery. The purpose of this article is to provide a comprehensive overview on tunneling flap procedures, to introduce the successive development of the approach along with underlying ideas on surgical wound healing and to present contemporary clinical scenarios in step-by-step photograph-illustrated sequences, which aim to provide clinicians with guidance to help them integrate tunneling flap procedures into their daily clinical routine.

Indocyanine green-mediated photothermal therapy in treatment of chronic periodontitis: A clinico-microbiological study

Background:

Photodynamic therapy (PDT) has developed as an alternative treatment modality in periodontitis patients. Different photosensitizers used over the years have shown contradictory results. Thus, recently indocyanine green (ICG)-mediated photothermal therapy has emerged for the treatment of chronic periodontitis.

Aim:

The present study aimed at comparing and evaluating the effects of photothermal therapy using ICG in the treatment of chronic periodontitis with scaling and root planing (SRP).

Materials and Methods:

This was a randomized, controlled, clinical trial where fifty participants were equally divided into two groups, i.e., control group (SRP) and test group (SRP + photothermal therapy). Clinical parameters were evaluated at baseline and 6-month follow-up. These were plaque index (PI), bleeding on probing (BOP), probing depth (PD), and clinical attachment level (CAL). Microbiological analysis of plaque sample was also done to check for anaerobic mixed flora.

Results:

Significant reduction was seen in PD, CAL, and BOP in the test group as compared to control group after 6 months (P < 0.05). However, intergroup comparison of PI showed nonsignificant results (P > 0.05). Anaerobic culture of plaque samples of test group also revealed a significant reduction of microorganisms in comparison with control group.

Conclusion:

ICG-mediated photothermal therapy can act as an alternative to antimicrobial PDT as an adjunct to SRP in the treatment of chronic periodontitis.

Comparison of serum tumor necrosis factor-α levels in rheumatoid arthritis individuals with and without chronic periodontitis: A biochemical study

Background

Tumor necrosis factor-alpha (TNF-α) is indicated to play a major function in chronic inflammatory disorders.

Objective

To assess and compare the cytokine level (TNF-α) in the serum of chronic periodontitis (CP), rheumatoid arthritis (RA), RA with CP, and healthy volunteers.

Materials and Methods

This original research was carried out on 80 participants, divided into Group-I 20 RA patients, Group-II 20 CP patients, Group III 20 RA with CP (RA + CP), and Group IV 20 healthy volunteers. Clinical periodontal and rheumatological parameters were assessed in all the four groups. Blood serum samples have been collected from all individuals and investigated for levels of TNF-α by mean of enzyme-linked immunosorbent assay.

Results

TNF-α level were remarkably elevated in the RA+CP group (30.5±2.2) followed by RA group (17.9 ± 3.6), and CP group (11.9 ± 0.96) when compared with the controls (5.5 ± 3.3). The results showed a statistical significance of P < 0.001. Correlation was not observed on comparision of clinical periodontal parameters and Rheumatological parameters with TNF-α levels.

Conclusion

The outcome of this present research revealed the presence of higher levels of TNF-α in individuals with RA with CP in our samples.

Quantum curcumin mediated inhibition of gingipains and mixed-biofilm of Porphyromonas gingivalis causing chronic periodontitis

Periodontitis is a biofilm-associated irreversible inflammation of the periodontal tissues. Reports suggest the role of Porphyromonas gingivalis specific Arg- and Lys-specific proteinases in the orchestration of the initiation and progression of periodontal diseases. These proteinases are precisely termed as gingipains R and K. Curcumin is an active polyphenol that is extracted from the rhizomes of Curcuma longa. However, the molecule curcumin owing to its high hydropathy index and poor stability has not been able to justify its role as frontline drug modality in the treatment of infectious and non-infectious diseases as claimed by several investigators. In the present study, at first, we synthesized and characterized quantum curcumin, and investigated its biocompatibility. This was subsequently followed by the evaluation of the role of quantum curcumin as an antimicrobial, anti-gingipains and antibiofilm agent against Porphyromonas gingivalis and select reference strains. We have successfully synthesized the quantum curcumin utilizing a top-down approach with the average size of 3.5 nm. Apart from its potent antimicrobial as well as antibiofilm properties, it also significantly inhibited the gingipains in a dose-dependent manner. At the minimal concentration of 17.826 μM, inhibition up to 98.7% and 89.4% was noted for gingipain R and K respectively. The data was also supported by the in silico docking experiments which revealed high exothermic enthalpies (−7.01 and −7.02 cal mol⁻¹). Besides, the inhibition constant was found to be 7.24 μM and 7.1 μM against gingipains R and K respectively. The results suggest that quantum curcumin is a potential drug candidate which needs further clinical validation.

Periodontitis is a biofilm-associated irreversible inflammation of the periodontal tissues.

Risk association between scleroderma disease characteristics, periodontitis, and tooth loss

Systemic sclerosis (SSc) is a multi-system disorder that can have significant adverse effects on the health of the mouth. The aim of this study was to investigate the associations between the disease characteristics of SSc, periodontal disease (PD), and tooth loss. Fifty-four patients affected by SSc and 55 non-diseased controls were matched for age and gender. SSc was characterized in subtypes and with the mean duration of disease and the Modified Rodnan Skin Score [mRSS]. Patients were surveyed and examined through the evaluation of the periodontal parameters and the number of teeth. A logistic regression analysis showed that patients with SSc presented a higher number of missing teeth (p = 0.001) and a significant median increased odds 2.95 (95% CI 1.26 to 6.84) of PD (defined as clinical attachment loss, CAL) compared to nondiseased controls (6.83, 95% CI 1.94 to 24.36). Moreover, the fewer values of PD was correlated with mRSS in the total SSc group and with the mean duration of disease in patients with limited SSc (p = 0.007), even after adjusting this correlation with the presence of the major organ involvement. This study showed that patients with SSc presented increased odds of PD and tooth loss compared to non-diseased controls. In SSc patients, the magnitude of PD was strongly associated with the mRSS and with the mean duration of the disease. The clinicians should be aware of the potential systemic health problems related to PD.

Comparison of the burr and chemically induced periodontal defects using different field-of-view sizes and voxel resolutions

OBJECTIVE

This study assessed the use of different voxel resolutions in a cone beam computed tomography (CBCT) unit for the detection of artificially induced periodontal bone defects created using burr, burr and chemicals, and only chemicals.

STUDY DESIGN

Seven dry skulls were used in this study. In total, 65 dehiscence defects, 43 fenestration defects, and 76 control sites with no periodontal defects were examined. Images were obtained from a CBCT unit (3 D Accuitomo; J Morita Mfg. Corp., Kyoto, Japan), using 3 field-of-view (FOV) sizes (4 × 4 cm; 6 × 6 cm; and 8 × 8 cm) and 4 scan modes (standard, high-definition, high-fidelity, and low-dose).

RESULTS

Overall, κ coefficients for interobserver agreement on burr-induced periodontal defects ranged from 0.336 to 0.795, with the lowest κ value (indicating a fair degree of agreement) obtained for images acquired in standard mode with a voxel size of 0.160 mm³. κ coefficients for the detection of periodontal defects were highest (indicating moderate to high degrees of interobserver agreement) for smaller voxel sizes and high-resolution images. Statistical comparison among groups (burr, burr + chemicals, and chemicals only) was performed using 1-way analysis of variance with post hoc tests.

CONCLUSIONS

The CBCT scan mode may affect the diagnosis of periodontal defects. The technique used to create periodontal defects also affected diagnosis. For this kind of experiment, burr-induced or burr + chemical-induced defects should be used, rather than those induced solely using a chemical technique.

High risk human papillomavirus in the periodontium : A case control study

BACKGROUND

Human papilloma viruses (HPVs) are small DNA viruses that have been identified in periodontal pocket as well as gingival sulcus. High risk HPVs are also associated with a subset of head and neck carcinomas. It is thought that the periodontium could be a reservoir for HPV.

AIMS

1. Detection of Human Papilloma virus (HPV) in periodontal pocket as well as gingival of patients having localized chronic periodontitis and gingival sulcus of periodontally healthy subjects. 2. Quantitative estimation of E6 and E7 mRNA in subjects showing presence of HPV3. To assess whether periodontal pocket is a reservoir for HPV.

SETTINGS AND DESIGN

This case-control study included 30 subjects with localized chronic Periodontitis (cases) and 30 periodontally healthy subjects (controls). Two samples were taken from cases, one from periodontal pocket and one from gingival sulcus and one sample was taken from controls.

METHODS AND MATERIALS

Samples were collected in the form of pocket scrapings and gingival sulcus scrapings from cases and controls respectively. These samples were sent in storage media for identification and estimation of E6/E7 mRNA of HPV using in situ hybridization and flow cytometry.

STATISTICAL ANALYSIS

Statistical analysis was done by using, mean, percentage and Chi Square test. A statistical package SPSS version 13.0 was used to analyze the data. P value < 0.05 was considered as statistically significant.

RESULTS

pocket samples as well as sulcus samples for both cases and controls were found to contain HPV E6/E7 mRNAInterpretation and.

CONCLUSION

Presence of HPV E6/E7 mRNA in periodontium supports the hypothesis that periodontal tissues serve as a reservoir for latent HPV and there may be a synergy between oral cancer, periodontitis and HPV. However prospective studies are required to further explore this link.

High Mobility Group Box 1 Protein Level as a Novel Biomarker for the Development of Peri-Implant Disease

Peri-implant disease is a chronic inflammation of the soft and hard tissues around a dental implant, resulting from bacterial infection. Recent evidence indicates that some pro-inflammatory cytokines and chemokines released by immunocytes are substantially responsible for the progress and consequence of inflammation. High mobility group box 1 (HMGB1) is released into the extracellular matrix and acts as a key pro-inflammatory factor during injury, necrosis and inflammation. A higher concentration of HMGB1 has been found in gingival crevicular fluid from inflammatory gingival tissue than from healthy sites. HMGB1 mRNA and protein are overexpressed in murine periodontal ligament fibroblasts stimulated with lipopolysaccharide (LPS) and IL-1β. Thus, this study sought to assess HMGB1 expression in peri-implant crevicular fluid (PICF) at each stage of peri-implant disease and to investigate the correlation between HMGB1 and peri-implant disease progress. The results demonstrated that the HMGB1 expression level in PICF is indicative of the progress of peri-implant disease and hence may be a useful diagnostic and prognostic biomarker for peri-implant tissue.

Efficacy of 1% Metformin Gel in Patients With Moderate and Severe Chronic Periodontitis: A Randomized Controlled Clinical Trial

BACKGROUND

The aim of this study is to investigate efficacy of metformin (MF) 1% gel as an adjunct to scaling and root planing (SRP) in the treatment of moderate and severe chronic periodontitis (CP).

METHODS

Seventy patients were categorized into two treatment groups: 1) SRP plus 1% MF and 2) SRP plus placebo. Clinical parameters were recorded at baseline and 3, 6, and 9 months. They included plaque index (PI), modified sulcus bleeding index (mSBI), probing depth (PD), and clinical attachment level (CAL). Radiologic assessment of intrabony defects (IBDs) and percentage defect depth reduction (DDR%) was done at baseline and 6- and 9-month intervals using computer-aided software. PD, CAL, and DDR% were evaluated in two subgroups in both the placebo and MF group: 1) initial PD of 5 to 7 mm and 2) initial PD of >7 mm.

RESULTS

Mean PD reduction and mean CAL gain was found to be greater in the MF group than the placebo group at all visits. Clinical parameters (PD, CAL) in both subgroups, with initial PDs of 5 to 7 and >7 mm, showed significant improvement in the 1% MF group compared with the placebo group. A significantly greater mean DDR% was found in the MF group than the placebo group at 6 and 9 months in both subgroups, 5 to 7 and >7 mm of initial PD.

CONCLUSION

There was a greater decrease in PD and more CAL gain with significant IBD depth reduction at sites treated with SRP plus locally delivered MF in patients with CP in both initial PD = 5 to 7 and >7 mm subgroups compared with placebo.