Background: Directing autogenous Mesenchymal Stem Cell (MSC) to defect sites has a great promise in bone regeneration. We designed a MSC specific, bone affinity peptide (E7HA7) by conjugating E7 with a polyglutamate hydroxyapatite (HA) binding motif. We sought to characterize the in-vivo releasing pattern and bioactivity of E7HA7. Methods: HA discs were coated with fluorescent labeled peptides E7HA7, E7HA2 or E7 were subcutaneously implanted in Sprague Dawley rats. In an ectopic bone formation model was used to test the in-vivo bioactivity of E7HA7 conjugated to DBM. Results: E7HA7 showed slower peptide release from scaffolds in comparison to other groups, being statistically significant at week 2 compared to E7, and to E7HA2 at week 4 and 8. In ectopic model, the medians for new bone formation in each group were: iDBM=0.041mm3, iDBM-E7=0.071mm3, aDBM=0.138mm3, and aDBM-E7=0.192mm3. Conclusions: Conjugation of E7 to polyglutamate bone binding domain showed slow releasing kinetics and osteoinductive potential.

Övervikt och fetma är ett stort hälsoproblem världen över. År 2008 var cirka 1,5 miljarder vuxna i världen överviktiga. Syftet med litteraturstudien var att undersöka om det finns en ökad förekomst av karies och parodontit hos vuxna personer med övervikt/fetma. Urvalet begränsades till vuxna som var 19 år eller äldre. Studien utfördes i form av en allmän litteraturstudie och materialet samlades in genom sökning i databaserna Pub Med och Science Direkt samt genom manuell sökning. Resultaten sammanställdes utifrån 14 vetenskapliga artiklar. Två vetenskapliga artiklar visade en ökad förekomst av karies hos personer med övervikt/fetma i jämförelse med personer som var normalviktiga. De andra artiklarna (n=2) som berörde karies hittade inget direkt samband mellan ökad kariesförekomst och övervikt/fetma. En ökad förekomst av parodontit hittades hos personer med övervikt/fetma i flera studier (n=4) vid jämförelse med normalviktiga deltagare. De resterande studierna (n=6) visade ett samband mellan förekomst av parodontit och personer med övervikt/fetma. Det tycks finnas en ökad förekomst av parodontit hos personer med övervikt/fetma då olika socioekonomiska faktorer eller andra förhållanden har betydelse. De fåtal artiklar som undersöktes visar att faktorer som kostvanor, saliv och munhygien är avgörande vid kariesförekomst. / Overweight and obesity are a huge health problem worldwide. Year 2008 it was about 1,5 billion adults that were overweight. The aim of this study was to investigate if there is an increased occurrence of dental caries and periodontal disease in adults with overweight/obesity. The study was limited to adults that were nineteen years old and above. The material was collected from the databases PubMed and Science Direct and a manual search. These results are based on fourteen scientific articles. Two scientific articles showed an increased occurrence of dental caries on persons with overweight/obesity compared with people who were normal weighted. The other studies (n=2) did not found a direct correlation between increased caries and overweight/obesity. The presence of periodontal disease in individuals with overweight/obesity was found to be increased significantly in several studies (n=4) compared to participants with normal weight. The other studies (n=6) showed a relation between occurrence of periodontitis and overweight/obesity. There seems to be an increased occurence of periodontitis in persons with overweight/obesity as several socio- economic factors or other conditions affect. The few scientific articles that were examined show that factors such as diet, saliva and oral hygiene are important in caries occurrence

Periodontal disease affects 47% of Americans over 30. Characterized by microbial dysbiosis and unregulated inflammation, severe periodontitis causes degradation of bone and soft tissue around teeth. Current treatments have limited regenerative outcomes and frequent reinfection by harmful bacteria. Human mesenchymal stem cells (hMSCs) have been shown to promote wound healing and tissue regeneration. Many therapeutic benefits of hMSCs are due to their secretome products, like exosomes. Our long-term goal is to develop periodontal therapies with hMSC exosomes. The objectives of this study were to determine the effect of hMSC-derived exosomes on cellular activity of hMSCs and investigate whether hMSC exosome treatment reduces pro-inflammatory cytokine production in LPS-activated RAW264.7 cells. The specific aims of this study were: 1) Determine the characteristics of hMSC-derived exosomes, 2) Determine the biological effect of exosomes on cellular activity of hMSCs, 3) Determine whether exosomes treatment can inhibit cytokine production in activated RAW264.7 cells, and 4) Determine the role of exosomal miRNA in pro-inflammatory cytokine production of RAW264.7 cells. To investigate, exosomes were first harvested from hMSCs culture media through ultracentrifugation. Exosomes were then observed under a transmission electron microscope (TEM) and assessed for surface markers using Western Blot. A transwell migration assay was used to evaluate the chemotactic effect of exosomes. To study the effect of exosomes on stem cell proliferation, exosomes were administered to hMSCs. The immunogenicity of MSC exosome was also evaluated. After 72 hours, cells were lysed and DNA was measured. To study anti-inflammatory effects of exosomes, LPS stimulated RAW264.7 cells were treated with exosomes. Interleukin-6 (IL-6) and tumor necrosis factor alpha (TNFα) levels of supernatant were measured by ELISA. To study exosomal miRNA, exosomal miRNAs were overexpressed in RAW264.7 cells and these cells were stimulated with LPS. IL-6 and TNFα were measured by ELISA. TEM images showed that exosomes are nano-sized vesicles (~100 nm). Western blot images showed that CD63 and CD81 are enriched in exosomes compared to total cell lysates. Exosome treatment increased cell proliferation and migration in hMSCs. At the doses that are chemotactic and mitogenic, MSC exosomes had minimal effect on the inflammatory cytokine IL-6 production. Treatment with exosomes significantly decreased IL-6 and TNFα production in RAW264.7 cells activated by LPS. Transfecting RAW264.7 cells with exosomal miR-760 significantly decreased IL-6 production, but had minimal effect on TNFα. Our results indicate that exosomes have a pleiotropic activity, which includes stimulating stem cell migration and proliferation, and mitigating the inflammatory response. Therefore, hMSC exosome delivery is promising for the treatment of periodontal diseases.

The dental community has a broad understanding of how traditional combustible cigarettes affect the oral cavity of the dental patient but there is little research available on the effects that e-cigarettes have on the patient’s dental health. Vaping products have been marketed as a healthier option over traditional combustible cigarettes. Since they were first introduced in 2003, very little research has been performed to understand their dental implications. This project was executed to investigate the chemicals associated with these vaping products and how they possibly contribute to the progression of periodontal disease. This research project was conducted with the contribution of 23 participants who confirmed the usage of vaping products via an anonymous online survey. Participants were dental patients of record at the University of Tennessee College of Dentistry. The data collected was analyzed and it was determined that there is a positive correlation between the use of e-cigarettes and the prevalence of periodontal disease.

Objectives: Since ultrasonic dental scalers contain internal narrow-diameter waterline tubing susceptible to bacterial biofilm growth, this study determined the cultivable prevalence of aerobic mesophilic heterotrophic bacteria in ultrasonic scaler output water subjected to one of two commercial biocides favorably reviewed by the American Dental Association as effective for microbial biofilm control in dental unit waterlines, and assessed the potential antimicrobial effect on output water of an ultrasonic scaler tip activated at a maximum power frequency. Methods: Aseptically-collected water samples were obtained, and neutralized for residual chlorine with sodium thiosulfate, from 12 ultrasonic scalers provided municipal tap water treated with an iodine resin cartridge (Group A), and from eight ultrasonic scalers provided distilled water treated with a 0.78% silver ion-based disinfectant (Group B), all within a dental school clinic setting. The latter eight ultrasonic scalers were additionally sampled after output water was passed through an inserted scaler tip activated to a maximum power setting similar to its potential use in clinical patient care. All water samples were evaluated for aerobic mesophilic heterotrophic bacteria using nationally-accepted analytical procedures detailed in Standard Methods for the Examination of Water and Wastewater, 23rd Edition (2017), with sample aliquots spread-plated onto R2A agar and aerobically incubated at 28°C for seven days. Aerobic mesophilic heterotrophic bacteria were considered elevated when ≥ 500 CFU/ml of the species were recovered per water sample. Predominant cultivable isolates of aerobic mesophilic heterotrophic bacteria in the water samples were identified using matrix- assisted laser desorption-ionization time-of-flight (MALDI-TOF) mass spectrometry and Bruker MALDI Biotyper analytic software. Results: Aerobic mesophilic heterotrophic bacteria averaged 610 ± 380 (SD) CFU/ml per ultrasonic scaler in Group A ultrasonic scalers, with eight of 12 (66.7%) evaluated ultrasonic scalers yielding elevated counts ≥ 500 CFU/ml. Similar mean values of 667 ± 340 (SD) CFU/ml per ultrasonic scaler were found in Group B ultrasonic scalers, with five of eight (62.5%) evaluated ultrasonic scalers yielding elevated aerobic mesophilic heterotrophic bacteria counts ≥ 500 CFU/ml. Acidovorax temerans, Novosphingobium subterraneum, Cupriavidus metallidurans, and Sphingobium yanoikuyae were the most prevalent cultivable species identified from ultrasonic scaler waterlines where the source water was municipal tap water treated with molecular iodine. In contrast, nearly pure growth of Cupriavidus metallidurans alone dominated cultivable waterline isolates from ultrasonic scalers where the source water was distilled water treated with a 0.78% silver ion disinfectant. No statistically significant impact was found on aerobic mesophilic heterotrophic bacterial counts after ultrasonic scaler output water passed through an inserted scaler tip activated to maximum power (P > 0.05, Wilcoxcon signed-rank test). Conclusions: Approximately two-thirds of ultrasonic scalers in a dental school clinic setting yielded output water that failed to meet potable water regulatory standards in the United States with regard to aerobic mesophilic heterotrophic bacterial counts, even when subjected to disinfection with one of two American Dental Association favorably-reviewed biocide products, or exposed to high-frequency ultrasonic scaler tip oscillations. These findings question the effectiveness of infection control procedures used to manage ultrasonic scaler waterlines, and raise concerns about the safety of ultrasonic scaler output water introduced into the oral cavity of dental patients during dental treatment procedures. / Oral Biology

Background: Unfavorable outcomes following periodontal surgeries can be attributed to impaired resolution mechanisms likely due to decreased levels of specialized pro-resolution molecules (SPM). The current study investigates if SPM substrate pools in platelet-rich plasma preparations (PRP) can be increased by essential fatty acid (EFA) and / or aspirin supplementation. Methods: Nineteen healthy volunteers were randomly assigned to take i) aspirin; ii) EFA; iii) aspirin and EFA. Four hours after intake, the lipid precursor pools in PRP were quantified using combined Liquid Chromatography tandem mass spectrometry (LC-MS/MS) and the data statistically analyzed using ANCOVA. Results: Of the 77 metabolites screened, only FFA (18:3) showed a significant interaction effect (p=0.019). By itself, neither EFA (p>0.9) nor aspirin (p>0.4) showed any difference (P>0.4). Multiple comparisons could not identify the differences between groups. Conclusions: There is inadequate data to support oral supplementation of EFA and /or aspirin to increase SPM levels in PRP.

Balance between matrix metalloproteinases (MMPs) and tissue inhibitors of matrix metalloproteinases (TIMPs) is required for normal wound healing. Chronic inflammation, such as that seen in cardiovascular and periodontal diseases, may upset this balance. The aim of this study was to determine whether initial periodontal therapy would have an effect systemically on the levels of MMP-9 and TIMP-1. Twenty-one patients with generalized chronic periodontitis were enrolled in the study. Clinical examinations were conducted and parameters measured. Scaling and root planing was performed and blood analysis done to determine the plasma concentrations of MMP-9 and serum concentrations of TIMP-1. Initial periodontal therapy resulted in improvements in gingival inflammation and plaque levels. No effect on the plasma concentrations of MMP-9 and serum concentrations of TIMP-1 could be found following therapy.

AIM: to determine if a relationship exists between TLR-2, TLR-4, TLR-9, or CD14 polymorphisms and risk for developing chronic periodontal disease in an African-American population. This is the first study conducted to determine role of SNPs in TLR genes and CD14 gene in a periodontally-diseased African-American population. Additionally, this is the first study to assess the role of TLR-9 polymorphism in periodontitis patients. METHODS: A total of 130 subjects were involved in the study. The chronic periodontitis (CP) group contained 73 subjects, and the healthy control (NP) group 57subjects. Genotyping was performed in TLR2 (G2408A), TLR4 (A896G),TLR9 (T1486C) and CD14 (C260T) genes by TaqMan® allelic discrimination using Assay-by-DesignSM SNP Genotyping Assays (Applied Biosystems). Accuracy of genotyping was confirmed by known DNA samples of each genotype and by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) analyses on selected samples. Fisher’s exact test and chi-square analyses were performed to compare genotype and allele frequencies. Within disease groups, we investigated whether SNPs were related to disease severity by step-wise logistic regression adjusted for age, gender, and smoking status. RESULTS: There was a significant difference in the distribution of specific TLR9 (T1486C) genotypes between the periodontally diseased group versus the control group. Expression of TT genotype was more prevelant in periodontally-diseased individuals compared to periodontally-healthy subjects (p<0.0001) whereas individuals expressing C allele of the TLR9 SNP (CC&CT) were more frequently found in the control group after adjusting for age, gender, and smoking status (p<0.0001) There was no statistically significant difference in the distribution of genotypes between groups for any other TLRs or CD14 polymorphism. CONCLUSION: Based on findings of this study, homozygocity for the T allele of TLR 9 polymorphism was related to chronic periodontal disease susceptibility in African Americans. Additionally, presence of the C allele at TLR-9 appeared to confer resistance to periodontal destruction. Our results showed that specific SNPs in TLR-2, -4 and CD14 genes are not related to periodontitis in African Americans.

Advanced biomaterials and sophisticated processing technologies aim to fabricate tissue-engineering scaffolds that can predictably interact within a biological environment at a cellular level. Sterilization of such scaffolds is at the core of patient safety and is an important regulatory issue that needs to be addressed prior to clinical translation. In addition, it is crucial that meticulously engineered micro- and nano- structures are preserved after sterilization. Conventional sterilization methods involving heat, steam and radiation are not compatible with engineered polymeric systems because of scaffold degradation and loss of architecture. Using electrospun scaffolds made from polycaprolactone (PCL), a low melting polymer, and employing spores of Bacillus atrophaeus as biological indicators, we compared ethylene oxide, autoclaving and 80% ethanol to a known chemical sterilant, peracetic acid (PAA), for their ability to sterilize as well as their effects on scaffold properties. PAA diluted in 20% ethanol to 1000 ppm or above, sterilized electrospun scaffolds in 15 min at room temperature while maintaining nano-architecture and mechanical properties. Scaffolds treated with PAA at 5000 ppm were rendered hydrophilic, with contact angles reduced to zero degrees. Therefore, PAA can provide economical, rapid and effective sterilization of heat-sensitive polymeric electrospun scaffolds used in tissue-engineering.

Periodontal disease (PD) is a polymicrobial infection characterized by inflammation of the gingiva, alveolar bone resorption, and tooth loss (edentulism). Treponema denticola along with Porphyromonas gingivalis and Tannerella forsythia are among the “Red Complex” and are main etiological agents in PD. Treponemes are a member of the Spirochaeta phylum and are obligate anaerobes, that express pyruvate ferredoxin oxidoreductase (PFOR). The enzyme catalyzes the oxidation of pyruvate to acetyl-CoA and reduced ferredoxin. Amixicile is a novel bacteriostatic derivative of nitazoxanide and an inhibitor of PFOR. In light of the fact that Treponemes express PFOR, this study was conducted to investigate the susceptibility of oral Treponemes to AMX. All oral Treponemes tested were susceptible to AMX and the MIC values were determined ranging of 1.5-4.5 μg mL-1 for an initial starting cell concentration of 1.9x106 cells mL-1. Other potentially therapeutic effects for AMX for T. denticola were investigated: motility, hydrogen sulfide production, and serum sensitivity. AMX reduced overall spirochete motility by 50% at sub-MIC concentrations. There was a dose dependent decrease in H2S production in T. denticola at sub-MIC and MIC values. Furthermore, prior exposure of AMX led to increases in serum sensitivity. Taking into account the fact that other periodontal red complex bacteria express PFOR, AMX could serve as a new selective adjunctive treatment for periodontal disease.