Bacteria and oral cavity: a new story to tell.

Periodontal diseases include a mild and reversible form named gingivitis (GI), and periodontitis (PD) that is the main cause of tooth loss in adults. GI, that affects gums and coronal junctional epithelium, as well as periodontitis, that is characterized by loss of connective tissue attachment, are caused by a persistent inflammatory response promoted by alteration of periodontal biofilm. The aim of the study was to test whether the prevalence of each species was associated with a particular clinical condition. Periodontal evaluation of 756 unrelated patients was performed by the Periodontal Screening and Recording (PSR) system. Subgingival samples were obtained from the site with the worst PSR score. A selection of eleven bacterial species was evaluated by quantitative real time PCR. Quantitative and qualitative analyses help to better understand the microbial changes associated with different stages of periodontal disease.

Hormones and dentistry: a two-way relationship.

Stem cells of dental pulp (SCDPs) are multipotent stem cells with the potential to differentiate into various cell types. For this reason, they have been proposed as an alternative source for mesenchymal stem cells. Somatostatin (ST) is a peptide hormone with an inhibitory effect on several endogenous hormones. The aim of our study is to investigate whether somatostatin can promote or inhibit differentiation of SCDPs in osteoblasts and bone tissue. SCDPs were extracted from third molars of healthy subjects and were treated with ST at the concentration of 100 ng/ml for 24 and 48 h. Gene expression in treated SCDPs was compared with untreated cells (control) to check the effect of somatostatin on stem cell differentiation. After 24 h of treatment many genes investigated were downregulated in treated SCDPs vs untreated SCDPs. Significantly up-regulated gene (Fold change >2) was the Bone Morphogenetic Protein BMP4. On the contrary ST induced the over-expression of bone related genes after 48 h of treatment. TGFB family genes and their receptors were also significantly upregulated after 48 h of treatment. ST demonstrated to promote the self-renewal of SCDPs: in our experiments somatostatin mainly acted on TGFB family genes. Further studies are needed to explore this new way of creating bone tissue.

Hyaluronic acid and its use in dentistry.

The purpose of this paper is to evaluate the role of hyaluronic acid in bio-revitalization (HABR) by testing several extracellular matrix biological parameters in cultured dermal fibroblasts. To this aim, fibroblastic expressed genes after exposition to three HABR medical devices were evaluated. Cells were seeded on a layer of three different medical devices containing 6.2, 10 and 20 mg/ml of HABR for 24 h. Real Time Polymerase Chain Reaction was performed to investigate gene expressions. Genes encoding HABR synthesis and degradation, Metalloproteinases 2 and 3 and Desmoplakin production as well as GDF6, and IGF1 were activated by hyaluronic acid products. The in vitro study showed similar effects on tested genes despite a different concentration of hyaluronic acid contained in the medical devices and the simultaneous presence of other additives. Based on the reported data, gene activations are an aspect of metabolic modulation of signalling pathways rather than the proportional production of a specific connective tissue molecule. Indeed, different HABR concentration and the presence of other additives did not change the overall effect on the studied genes. We believe that the optimization of extracellular matrix micro-environment, obtained by enhanced structural support with HABR, leads to functional and metabolic improvement.

Silica solutions (SL) is efficacy in the treatment of chronic periodontitis: a case control study.

AIM: The objective of this study was to compare the efficacy of supportive periodontal therapy (i.e. scaling and rooth planning, SRP) alone versus a chemical device silica dioxide (SiO2) colloidal solutions (SL) used in association with SRP in the treatment of chronic periodontitis in adult patients. MATERIALS AND METHODS: A total of 20 patients with a diagnosis of chronic periodontitis (40 localized chronic periodontitis sites) in the age group of 35 to 55 were selected. None of these patients have previously received any surgical or non-surgical periodontal therapy and demonstrated radiographic evidence of moderate bone loss. Two non-adjacent sites in separate quadrants were selected in each patient to monitorize treatment efficacy (split mouth design). Clinical pocket depth (PD) and microbial analysis (MA) were analyzed at baseline and 15th day. SPSS program and paired simple statistic T-test were used to detect significant differences. RESULTS: Total bacteria loading, Tannerella Forsitia and Treponema Denticola loading were statistically reduced when SiO2 is locally delivered. CONCLUSIONS: SL gel is an adiuvant therapy which should be added to SRP in the management of moderate to severe chronic periodontitis.

Efficacy ozone therapy in reducing oral infection of periodontal disease: a randomized clinical trial.

Periodontal diseases are among the most common infectious diseases in the world, caused by pathogenic bacteria that trigger innate, inflammatory, and adaptive immune responses, leading to the destruction of supporting periodontal tissues and, if untreated, tooth loss. The objective of this study was to explore the efficacy of medical device that produced ozonized water (Medica S.r.l. Bologna, Italy) in the treatment of chronic periodontitis of adult patients. A randomized controlled split-mouth study was carried out in ten patients (5 men and 5 women age 42-73 mean 55 ± 7) with a diagnosis of chronic periodontitis. None of these patients received any surgical or non-surgical periodontal therapy and demonstrated radiographic evidence of moderate bone loss. The mouth has been divided into upper right and left quadrants. The upper and lower right quadrants were treated with ultrasonic scaler, the left quadrants with ultrasonic scaler with ozonated water. Ten microbiological samples were collected from upper left quadrants and 10 from upper right quadrants from each patient. Microbiological samples were collected from the sites of the patients at baseline and at the 7th day. Twenty localized chronic periodontitis sites were selected (10 in left quadrants and 10 in right quadrants). After the treatment with ozonized water, a remarkable decrease in bacteria amount, both for some species and for the total count was observed in the left quadrants respect to right ones. Our study demonstrated the efficacy of the ozonized water in the management of moderate to severe chronic periodontitis.

Preventive contamination with Lactobacillus reuteri of the implant-abutment connection: an in vivo study.

The aim of this study is to preventively contaminate the abutment-fixture connection (AFC) with Lactobacillus reuteri(L. reuteri), to evaluate the presence of micro leaks in different types of implant-abutment connections, by measuring the concentration of (L. reuteri), in the sulcular fluid over time. This microorganism produces the Reuterine, an antibiotic which counteracts the development of other microbial species. Fourteen biphasic implants were placed on 10 patients (3 women; 7 men; mean age 55.9±16.54y). Eight implants had a flat top connection (internal Hex) while six implants had a tapered connection (conical plus octagonal). At the time of prosthetic finalization, before the healing screw was removed, the sulcular fluid was harvested, on each implant, by means of three sterile paper cones placed into the gingival sulcus and left in place for 20 sec before to be transferred to a sterile tube. Once the healing screw has been removed, first the implant connection has been gently dried with air jet for 10sec and then completely filled with (L. reuteri) DSM 17938 (Reuflor, Italchimici, Italy). Immediately after the prosthetic finalization the sulcular fluid was then harvested again, with the same procedure described before and repeated at 1 week and 1 month of follow up. The samples were then sent for subsequent DNA extraction and real-time PCR. Our results demonstrate that the concentration of (L. reuteri), in the sulcular fluid, does not persist over time in case of preventive contamination of the AFC, demonstrating no significative differences between flat top and tapered connections. Therefore, the use of the latter does not lead to a lower risk of Peri Implant Disease (PID). Long-term studies, involving a larger number of samples, are advisable to confirm these findings.

Colonization of Legionella spp. In dental unit waterlines.

Legionella spp. are ubiquitous in aquatic habitats and water distribution systems, including dental unit waterlines. Surveys have shown that the percentage of samples taken at different dental sites that were positive for Legionella spp. were highly variable and ranged from 0% to 100%. Cultivation is the principal approach to evaluating bacterial contamination employed in the past, but applying this approach to testing for Legionella spp. may result in false-negative data or underestimated bacterial counts. PCR and direct fluorescent counts can detect viable non-cultivable bacteria, which are not counted by plating procedures. Legionella spp., commonly form such viable non-culturable cells and it is likely that they contribute to the difference between plate count results and those of PCR and fluorescent-antibody detection. However, studies have shown that Legionella is present in the municipal water source in spite of the current filtration and chlorination procedures. Once Legionella reaches the building water system, it settles down into a biofilm layer of stagnant water. By means of this layer, Legionella can protect itself from antimicrobial agents and then multiply. Dental unit waterlines may be contaminated with opportunistic bacteria. The water quality in the dental units should be controlled to eliminate opportunistic pathogens and to provide water for dental treatment that meets public health standards for potable water.

Focus on periodontal disease and development of endocarditis.

Infective endocarditis is a devastating disease with high morbidity and mortality. The link to oral bacteria has been known for many decades and has caused ongoing concern for dentists, patients and cardiologists. The microbiota of the mouth is extremely diverse and more than 700 bacterial species have been detected. Half of them are uncultivable so far. Oral microbiota is not uniform, specific sites exist in the mouth such as tongue, palate, cheek, teeth and periodontal pockets that have their own microbiota. Factors involved in the development of a bacterial endocarditis are difficult to define but a vulnerable surface (i.e. a damaged endocardium) and a high bacterial load in the blood seems to be decisive. The cause of microorganisms, in 90% of cases, are staphylococcus, streptococcus and enterococcus. Oral streptococci belong to viridans group (streptococcus mutans and streptococcus sanguis). As they are part of dental plaque, they could enter the bloodstream causing bacteraemia through daily habits like chewing or tooth brushing. Effective treatment of periodontal infections is important to reduce local inflammation and bacteraemia. In addition, poor periodontal health appears to increase the risk of cardiovascular disease, pulmonary disease, and preterm and low birth weight. CONCLUSIONS: Long-standing oral disease prevention protocols reduce the risk of developing periodontal disease. Data suggests that methods used to prevent cases of IE that originate from oral bacteria should focus on improving oral hygiene and reducing or eliminating gingivitis, which should reduce the incidence of bacteraemia after tooth-brushing and the need to extract teeth owing to periodontal disease and caries.

Bacterial load of periodontal pathogens among italian patients with chronic periodontitis: a comparative study of three different areas.

The aim of the present study was to evaluate the mean bacterial load of some periodontal pathogenic bacteria in Italian patients affected by chronic periodontitis. The sample consisted of 1,762 patients with a clinical diagnosis of chronic periodontitis based on the criteria of the American Academy of Periodontology sampled in the period 2013-2015; 1,323 patients were from Northern Italy, 317 from Central Italy and 122 from Southern Italy. Samples for microbiological analysis were collected from the four sites of the greatest probing depth in each patient and then processed by quantitative polymerase chain reaction. Periodontal pathogens have the following percentage respect to total bacteria load: Aggregatibacter actinomycetemcomitans 0.1%, Campylobacter rectus 2%, Fusobacterium nucleatum 8%, Porphyromonas gingivalis 6%, Treponema denticola 2% and Tannerella forsythia 1.5%. There are significant differences in bacterial load among the different geographical areas both for the total bacterial and for the single species. The results of our study in this Italian population showed that a different geographic distribution exists among periodontal pathogens. We hypothesize that these differences in bacterial load could be related to genetic and environmental factors. Additional studies are necessary to confirm these data and to get more insight on additional factors, which may play a role in periodontal pathogens in different geographic areas.

Infectogenomics: lack of association between VDR, IL6, IL10 polymorphisms and “red complex” bacterial load in a group of Italian adults with chronic periodontal disease.

Periodontitis is a multifactorial disease that, if untreated, may cause teeth loss. Clinicians and researchers have reported that genetic factors influence the clinical manifestations of periodontal disease (PD), modulating both inflammation of the mucous membranes and loss of alveolar bone. The acquisition of new nowledge about genetic susceptibility of PD, would directly impact on prognosis and treatment of the disease. In addition, a better understanding of PD pathogenesis could improve the diagnostic tools for the prevention and therapies for modulation of immune responses and treatment of PD. In this study, we evaluated genetic polymorphisms of VRD, IL6 and IL10 and amounts of periodontal pathogens in Italian adults affected by PD. We included 326 cases classified according the criteria of the American Academy of Periodontology. No significant differences in bacterial load were found in patients carrying PD susceptibility alleles of IL6, IL10 and VDR genes. In conclusion, no interaction between genetic factors and amount of periodontal pathogens in periodontal pockets were found in PD patients.

Why should patients with systemic disease and tobacco smokers go to the dentist?

Periodontal diseases (PD) affect about half of the adult population all over the world. PD is caused by bacterial infection which induces an inflammatory response with progressive destruction of the periodontal tissues and finally the loss of teeth. Tobacco smoking (TS), alcohol consumption, and systemic diseases (SDs), such as cardiovascular diseases, diabetes mellitus, respiratory diseases, osteoporosis, malnutrition and stress, are considered additional risk factors. This short review examines the potential causal association between PD, TS and SDs. There is strong evidence that PD is associated with an increased risk of SDs. In addition, many patients with SDs are also affected by PD, which can be mild or severe, and tobacco smokers manifest a greater risk of developing PD. The aim of this manuscript is to investigate the effects of periodontal therapy on the management of SDs and influence of TS on PD. This manuscript includes many randomized controlled trials and reviews to test the effects of different periodontal therapies for patients with SDs. A definite conclusion on the relationship between PD and SDs is lacking, however, there is sufficient evidence to justify periodontal treatment to prevent SDs; in fact, PD is prevalent in the middle-aged population and can have a significant impact on systemic health.

The ecological catastrophe of oral diseases: a possible link between periodontitis and protozoa.

Periodontal disease (PD) is one of the prevalent diseases in the adult population. The ethiology of PD has never been completely understood, however, loss of balance between the host immune system and the microbial virulence of PD pathogens may be considered the trigger of PD. In fact, the immune system, activated by microbiological agents, attacks the host and not the biofilm bacteria, causing the destruction of periodontal tissue, alveolar bone and loss of teeth. Parasites may play an important role in the pathology of PD. The first studied and the most common parasite in the oral cavity is Entamoeba gingivalis. A possible link between E. gingivalis and PD has never been demonstrated completely, however E. gingivalis is infrequently found in people without PD. In addition, there is evidence that E. gingivalis could favour the onset and progression of PD. In conclusion, we can assert that E. gingivalis and PD may be correlated. This relationship can open new therapeutical approaches for treating PD, particularly in cases refractory to therapy.

EVALUATION OF THE EFFICACY OF TITANIUM DIOXIDE WITH MONOVALENT SILVER IONS COVALENTLY LINKED (TIAB) AS AN ADJUNCT TO SCALING AND ROOT PLANING IN THE MANAGEMENT OF CHRONIC PERIODONTITIS USING PCR ANALYSIS: A MICROBIOLOGICAL STUDY.

The use of chemical devices for non-surgical periodontal therapy has led to new treatment strategies aimed primarily at controlling infection. Over the last few years, titanium dioxide (TiO2) with monovalent silver ions (A) covalently linked and added to benzalkonium (B) (named TIAB) has been subjected to medical studies, especially in dermatology. The purpose of the present study was to assess the effect of TIAB on the red complex bacteria using Polymerase Chain Reaction (PCR) for microbiological analysis. A split mouth study was conducted, and 10 subjects were enrolled. TIAB as topical medication was placed at study sites after scaling and root planing. Sub-gingival plaque samples were collected after 2 weeks, and red complex micro-organisms were studied using PCR. SPSS program was used for statistical purposes and a paired sample correlation was performed at the end of the observation period between treated and untreated sites. The results showed statistically significant reduction of red complex organisms in the study compared to the control group. TIAB can be used as an effective local drug along with supportive periodontal therapy in treatment of chronic periodontitis.

PERIODONTAL POCKETS AS A RESERVOIR OF HELICOBACTER PYLORI CAUSING RELAPSE OF GASTRIC ULCER: A REVIEW OF THE LITERATURE.

Helicobacter pylori (HP) is one of the most common gastric infections in the world, affecting about half the world’s population and is the principal cause of adenocarcinoma of the distal stomach. It seems that HP infects the subject early in life and is transmitted from person to person. The HP reaches the stomach through oral ingestion, and because of its non-invasive nature, the stomach is the ultimate site of colonization. Recently, it has been debated whether the oral cavity is a reservoir of HP bacteria participating in infection transmission, or representing a nidus of re-infection after eradication of the bacterium. HP and recurrent aphthous stomatitis (RAS) show similar clinical and histological findings, and the discovery of HP in RAS ulcers support the idea of a correlation between the two diseases. Another important relationship between RAS and HP is the high incidence of anemia in patients with RAS that may be caused by HP-positive stomach disease. In fact, antibiotic therapy and treatment of anemia can reduce the frequency of RAS ulcer recurrence. HP is considered a carcinogenic agent type 1 of the stomach by the International Agency for Research on Cancer. In conclusion, the oral cavity is an extra-gastric reservoir of HP and periodontal therapy associated with systemic therapy can better eradicate HP from the mucosa of all gastro-enteric tract, reducing relapse of HP infection. Prospective cohort studies are needed to demonstrate the bacterial action in the oral cavity.

Genetic susceptibility and periodontal disease: a retrospective study on a large italian sample.

BACKGROUND: Periodontal disease (PD) is a multifactorial illness in which environment and host interact. The genetic component plays a key role in the onset of PD. In fact the genetic compound can modulate the inflammation of the mucous membranes and the loss of alveolar bone. The genetics of PD is not well understood. Previous studies suggest a strong association between PD occurrence and individual genetic profile. The role of genetic susceptibility could impact on the clinical manifestations of PD, and consequently on prevention and therapy. MATERIALS AND METHODS: Genetic polymorphisms of VRD, IL6 and IL10 were investigated in Italian adults affected by PD. 571 cases classified according the criteria of the American Academy of Periodontology were included. All patients were Italian coming from three areas according to italian institute of statistics (ISTAT) (www.istat.it/it/archivio/regioni). The sample comprised 379 patients from North (66%), 152 from Central (26%) and 40 of South (8%). RESULTS: No significant differences were found among allele distribution. CONCLUSION: Chronic PD is a complex disease caused by a combination of genetic susceptibility, patients habits (oral hygiene, smoking, alcohol consumption) and oral pathogens. In our report no differences were detected among three Italian regions in allele distribution.

Prevalence of periodontal pathogens among italian patients with chronic periodontitis: a retrospective study on 2992 patients.

PURPOSE: The aim of the present study was to evaluate the prevalence of some periodontal pathogens in Italian adults with chronic periodontitis. MATERIALS AND METHODS: The sample consisted of 2992 patients with a clinical diagnosis of chronic periodontitis, based on the criteria of the American Academy of Periodontology, sampled in the period 2013-2016: 2108 patients were from Northern, 690 from Central and 194 from Southern Italy. Porphyromonas gengivalis, Treponema denticola, and Tannerella forsythia were investigated in all patients of the present study, while Campylobacter rectus, Fusobacterium nucleatum and Aggregatibacter actinomycetemcomitans only in 2514 (84%) patients. Subgingival plaque samples of the four sites of greatest probing depth in each patient were used to obtain subgingival microbiota and then processed by quantitative polymerase chain reaction. RESULTS: Periodontal pathogens had the following presence respect to all amount of patients: Aggregatibacter actinomycetemcomitans 16.1%, Campylobacter rectus 73.4%, Fusobacterium nucleatum 93.8%, Porphyromonas gengivalis 65.5%, Treponema denticola 66.4%, and Tannerella forsythia 72.7%. There are no significant statistical differences among geographic areas both for the total bacterial and the single species except for T. Denticola and C. Rectus, which prevalence was significantly higher in Southern Italy (P value <.05). The other investigated species were equally distributed among different regions. A. actinomycetemcomitans was the rarer species detected in this study, while F. nucleatum was the commonest. No differences among areas where observed as regard of the mean bacterial load except for F. Nucleatum whose prevalence in Northern Italy was lower then both in Central and Southern Italy (P value <.05). CONCLUSIONS: The results of our study didn't show different geographic distribution of periodontal pathogens among Italian population of the three areas investigated. The homogeneity of the results could be related to genetic and environmental factors.