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Background Evidence suggests that periodontitis is associated with prevalent and incident type 2 diabetes mellitus (T2DM), raising the question of whether periodontitis treatment may improve glycemic control in patients with T2DM. Meta-analyses of mostly small clinical trials suggest that periodontitis treatment results in a modest reduction in glycosylated hemoglobin (Hb) A1c. Purpose The purpose of the Diabetes and Periodontal Therapy Trial (DPTT) was to determine if periodontal treatment reduces HbA1c in patients with T2DM and periodontitis. Methods DPTT was a phase-III, single-masked, multi-center, randomized trial with a planned enrollment of 600 participants. Participants were randomly assigned to receive periodontal treatment immediately (Treatment Group) or after 6 months (Control Group). HbA1c values and clinical periodontal measures were determined at baseline and 3 and 6 months following randomization. Medication usage and dosing were assessed at each visit. Periodontal treatment consisted of scaling and root planing for a minimum of two 90-minute sessions, plus the use of an antibacterial mouth rinse for at least 32 days afterwards. The primary outcome was change in HbA1c from baseline to 6 months and the trial was powered to detect a between-group difference of 0.6%. Secondary outcomes included changes in periodontal clinical measures, fasting plasma glucose, the Homeostasis Model Assessment (HOMA2) and the need for rescue diabetes or periodontal therapy. Conclusion Dental and medical researchers collaborated to recruit, treat and monitor participants with two chronic diseases to determine if treatment of one condition affects the status of the other.

Introduction: Diode laser irradiation has recently shown promising results for treatment of gingival pigmentation. This study sought to compare the efficacy of 2 diode laser irradiation protocols for treatment of gingival pigmentations, namely the conventional method and the sieve method. Methods: In this split-mouth clinical trial, 15 patients with gingival pigmentation were selected and their pigmentation intensity was determined using Dummett's oral pigmentation index (DOPI) in different dental regions. Diode laser (980 nm wavelength and 2 W power) was irradiated through a stipple pattern (sieve method) and conventionally in the other side of the mouth. Level of pain and satisfaction with the outcome (both patient and periodontist) were measured using a 0-10 visual analog scale (VAS) for both methods. Patients were followed up at 2 weeks, one month and 3 months. Pigmentation levels were compared using repeated measures of analysis of variance (ANOVA). The difference in level of pain and satisfaction between the 2 groups was analyzed by sample t test and general estimate equation model. Results: No significant differences were found regarding the reduction of pigmentation scores and pain and scores between the 2 groups. The difference in satisfaction with the results at the three time points was significant in both conventional and sieve methods in patients (P = 0.001) and periodontists (P = 0.015). Conclusion: Diode laser irradiation in both methods successfully eliminated gingival pigmentations. The sieve method was comparable to conventional technique, offering no additional advantage.

Introduction Educating dental practitioners is a major component in obtaining evidence-based approach to oral health care, but there is no evidence about knowledge and attitude of dental faculty members towards evidence-based dentistry (EBD) in Iran. Materials and methods A cross-sectional study was conducted using self-administered questionnaires on dental school faculties in Iran to assess their knowledge and attitude towards basic principles and methods of EBD. A total of eight dental schools were randomly selected of 17 public and two existing private schools. Validated questionnaire with an appropriate reliability (Cronbach's alpha 0.67 – 0.87) was conducted on (n = 505) available dental instructors. The covered dimensions were perceived knowledge on critical appraisal, actual knowledge of EBD concepts, evidence-accessing methods and attitudes about EBD. Correlations were assessed between background characteristics and four main parts of the questionnaire, and multiple linear regression analysis was also used. Results A total of 377 of 505 dental instructors returned completed questionnaires (response rate 74.65%). The mean perceived knowledge score was 15.32 ± 4.69 on a range of 6–36, and mean actual knowledge was 7.98 ± 2.0 on a range of 0–11 for all respondents with an overall positive attitude towards EBD. Conclusions This study suggests that the level of actual knowledge of dental faculties about basic principles of EBD was moderate in Iran. However, faculties' overall interest and positive attitude towards learning EBD is encouraging. Therefore, it is highly recommended that degree/certificate continuing educational programmes be planned by the organising committees.

Low-level laser therapy (LLLT) has been used to accelerate wound healing, yet questions remain concerning its therapeutic applications. This study aimed to compare the healing efficacy of helium-neon (He-Ne) red light (laser) and gallium aluminum arsenide (Ga-Al-As) infrared lasers at two different doses on hard palate wounds. In a randomized controlled study, 75 adult male mice were divided into five groups of 15 each, after undergoing identical surgical procedures; a control group, with no laser irradiation; HD1 and HD2 groups, treated with He-Ne laser (wavelengths 632.8 nm, power 5 mW, and spot size 0.02 cm(2)) at doses of 4 J/cm(2) and 7.5 J/cm(2) respectively; and GD1 and GD2 groups, treated with Ga-Al-As laser (wavelengths 830 nm, peak power 25 mW, and spot size 0.10 cm(2)) at the doses of 4 J/cm(2) and 7.5 J/cm(2), respectively. Five animals from each group were killed on the third, seventh, and 14 days after surgery, and biopsies were made for histological analysis. On the 3rd and 7th day after the surgery, the number of polymorphonuclear cells (PMN) in HD1, HD2, GD1, and GD2 groups was significantly lower than that of the control group. On the 7th and 14th day, the fibroblasts and new blood vessels counts and collagen density fibers in HD1, HD2, GD1, and GD2 groups were also significantly higher than that of the control groups, and the fibroblast counts and collagen density fibers in HD1 and HD2 groups were higher than that of the GD1 and GD2 groups. LLLT with He-Ne laser compared to Ga-Al-As laser has a positive healing effect on hard palate gingival wounds in mice regardless of the radiation dose.

Background amd Objective: Periodontitis is a multifactorial disease in which environmental and genetic determinant factors contribute to individual subject’s susceptibility. A DNA polymorphism in the regulating region of adhesion molecule genes is suggested to modulate the molecule’s physiological effects. The aim of this study was to investigate the genetic association between the E-selectin Ser128Arg and L-selectin Phe206Leu polymorphisms and periodontitis. Material and Methods: DNA was isolated from the whole blood of 88 patients with periodontitis and 139 healthy individuals. All samples were genotyped for the E-selectin Ser128Arg and L-selectin Phe206Leu polymorphisms using the polymerase chain reaction with sequence specific primers. Results: Our findings revealed a significant difference in the Ser128Arg polymorphism of E-selectin, but not in the L-selectin polymorphism, between periodontal patients and controls. The 128Arg allele was present more frequently in patients than in healthy individuals (31.25% vs. 12.2%, p

Tissue expansion is used by plastic/reconstructive surgeons to grow additional skin/tissue for replacing or repairing lost or damaged soft tissues. Recently, hydrogels have been widely used for tissue expansion applications. Herein, a self-inflating tissue expander blend composition from three different molecular weights (2, 6, and 10 kDa) of poly (ethylene glycol) diacrylate (PEGDA) hydrogel with tunable mechanical and swelling properties is presented. The in vitro results demonstrate that, of the eight studied compositions, P6 (PEGDA 6 kDa:10 kDa (50:50)) and P8 (PEGDA 6 kDa:10 kDa (35:65)) formulations provide a balance of mechanical property and swelling capability suitable for tissue expansion. Furthermore, these expanders can be compressed up to 60% of their original height and can be loaded and unloaded cyclically at least ten times with no permanent deformation. The in vivo results indicate that these two engineered blend compositions are capable to generate a swelling pressure sufficient to dilate the surrounding tissue while retaining their original shape. The histological analyses reveal the formation of fibrous capsule at the interface between the implant and the subcutaneous tissue with no signs of inflammation. Ultimately, controlling the PEGDA chain length shows potential for the development of self-inflating tissue expanders with tunable mechanical and swelling properties.

Purpose To increase the understanding of the applicability of biomaterials and growth factors in enhancing stem cell-based bone regeneration modalities, this study evaluated the effects of enamel matrix derivative (EMD) and recombinant human transforming growth factor-beta (rhTGF-β) on osteoblastic differentiation of human bone marrow mesenchymal stem cells (hBMSCs) as well as human periodontal ligament stem cells (hPDLSCs). Materials and methods hBMSCs and hPDLSCs were obtained, and identification of stem cell surface markers was performed according to the criteria of the International Society for Cellular Therapy. Each group of stem cells was separately treated with a serial dilution of EMD (10, 50, and 100 μg/mL) or rhTGF-β (10 ng/mL). Osteoblastic differentiation was examined through in vitro matrix mineralization by alizarin red staining, and mRNA expression of osteopontin and osteonectin was determined by quantitative reverse-transcriptase polymerase chain reaction. hPDLSCs were further assessed for osteocalcin mRNA expression. Stem cells cultured in osteogenic medium were employed as a standard positive control group. Results In none of the experimental groups were bone-related mRNAs detected subsequent to treatment with EMD for 5, 10, and 15 days. Alizarin red staining on day 21 was negative in EMD-treated BMSC and PDLSC cultures. In rhTGF-β-supplemented BMSC culture, expression of osteonectin mRNA was demonstrated on day 15, which was statistically comparable to the positive control group. Nevertheless, extracellular matrix mineralization was inhibited in both groups of stem cells. Conclusions Within the limitations of this study, it could be concluded that EMD with a concentration of 10, 50, or 100 μg/mL has no appreciable effect on osteoblastic differentiation of BMSCs and PDLSCs. Application of rhTGF-β increased osteonectin mRNA expression in BMSCs. This finding corroborates the hypothesis that TGF-β might be involved in early osteoblastic maturation.

Background: Allium sativum, commonly known as garlic, exhibits antibacterial effects against a wide range of bacteria. Aim: The objective of this in vitro study was to assess the antibacterial effect of different concentrations of garlic extract against human dental plaque microbiota. Materials and Methods: Antibacterial activities of four different concentrations of garlic extract (5%, 10%, 20%, and 100%) were evaluated against Streptococcus mutans, Streptococcus sanguis, Streptococcus salivarius, Pseudomonas aeruginosa, and lactobacillus spp. using the disk diffusion method. Papers soaked in 0.2% concentration chlorhexidine gluconate and saline were used as positive and negative controls, respectively. The data were subjected to one-way ANOVA and the Tukey multiple comparisons test at a 5% significance level. Results: All bacterial strains were inhibited by all test materials. The inhibition zones of the different concentrations of garlic extract were not significantly different for S. mutans, S. sanguis, and S. salivarius. For P. aeruginosa and lactobacillus spp. the inhibition zones of 5%, 10% and 20% concentrations were not significantly different from one another, but they were significantly more than that of the 100% extract. Conclusion: The 5%, 10%, 20%, and 100% concentrations of garlic extract had similar effects, so further studies seem to be indicated on the usefulness of the 5% extract.

Among several bacteria examined, an antibacterial-producing Lactobacillus strain with probiotic characteristics was selected and identified based on 16S rRNA gene sequencing. Subsequent purification and mode of action of the antibacterial compounds on target cells including E. coli were investigated. Maximum production of the antibacterial compound was recorded at 18 h incubation at 30 degrees C. Interestingly, antibacterial activity remained unchanged after heating at 121 degrees C for 45 min, 24 h storage in temperature range of 70 degrees C to room temperature, and 15 min exposure to UV light, and it was stable in the pH of range 2-10. The active compounds were inactivated by proteolytic enzymes, indicating their proteinaceous nature, and, therefore, referred to as bacteriocin-like inhibitory substances. Isolation and partial purification of the effective agent was done by performing ammonium sulfate precipitation and gel filtration chromatography. The molecular mass of the GFC-purified active compound (~3 kDa) was determined by Tris-Tricine SDS-PAGE. To predict the mechanisms of action, transmission electron microscopy (TEM) analysis of ultrathin sections of E. coli before and after antibacterial treatment was carried out. TEM analysis of antibacterial compounds-treated E. coli demonstrated that the completely altered bacteria appear much darker compared with the less altered bacteria, suggesting a change in the cytoplasmic composition. There were also some membrane-bound convoluted structures visible within the completely altered bacteria, which could be attributed to the response of the E. coli to the treatment with the antibacterial compound. According to the in vivo experiments oral administration of L. plantarum HKN01 resulted in recovery of infected BALB/c mice with Salmonella enterica ser. Typhimurium.

Objective.Our aim in this paper was to investigate the possible genetic association between three Ser563Asn, Leu125Val and Arg670Gly polymorphisms of the PECAM-1 gene and periodontitis.Methods.Genomic DNA was isolated from whole blood of 105 periodontal patient (52 with chronic periodontitis and 53 with aggressive periodontitis) and 101 healthy individuals. Samples were genotyped and analyzed for the three single-nucleotide polymorphisms (SNPs) of PECAM-1 using polymerase chain reaction with sequence-specific primers (PCR-SSPs).Results.A statistically significant difference was found between the genotypic distribution of the Ser563Asn polymorphism in patients with periodontitis compared to controls (P=0.02). But there were no statistically significant difference between the allele frequencies in the different groups (P=0.05). The other two polymorphisms did not show a statistically significant difference in their allele and genotype frequencies between the groups. There was no statistically significant difference found for any of the polymorphisms allele and genotype distribution in aggressive and chronic periodontitis either.Conclusions.No significant association was found between the polymorphism tested and the subgroups of periodontitis, further research is still necessary to determine whether this polymorphism can be used as a genetic marker of periodontitis.

Aim Persistent host inflammatory immune response against the pathogens results in the destruction of periodontal tissues. Cytotoxic T lymphocyte antigen 4 (CTLA-4) is a particularly important molecule in down-regulating T-cell expansion and cytokine production. This study aimed to assess three functional SNPs within CTLA-4 gene, −1722 T/C, −318 C/T, and +49 A/G in patients with aggressive or chronic periodontitis. Materials and methods A total of 197 patients with periodontitis (71 aggressive and 126 chronic periodontitis) and 218 healthy controls were recruited. All samples were genotyped for CTLA-4 gene polymorphisms by polymerase chain reaction-amplification refractory mutation system (PCR-ARMS). Results The allelic and genotype frequencies of only +49 A/G SNP were more prominence in patients with chronic periodontitis (CP) than that controls (0.0005 and 0.001, respectively). Multivariate logistic regression analysis was demonstrated that homozygosity in +49 G/G had profoundly increased susceptibility for CP, OR = 3.7 (95% CI; 1.6–8.5, P = 0.001). In addition, comparison of CTLA-4 SNPs between patients with CP and aggressive periodontitis (AgP) revealed that heterozygosity in −1722 T/C polymorphism of CTLA-4 gene had a significantly higher risk for CP compared with AgP with a calculated odds ratio of 2.18 (95% CI; 1.17–4.06, P = 0.01). Conclusion These results suggest that CTLA-4 gene variants might be associated to susceptibility to specific form of periodontitis and participate in the CP development.

The effect on bone regeneration, of adding pamidronate disodium to bovine-derived hydroxyapatite, was histologically evaluated, using the sheep bone model.Twenty-four intrabony defects were prepared in the lower jaw of eight sheep using trephine 6 mm burs. One cavity was left unfilled and the other two were filled with bovine-derived hydroxyapatite (BioOss) alone (control group) or with bovine-derived hydroxyapatite mixed with pamidronate disodium (Aredia) (case group), respectively. After 6 wk, the animals were killed and the coded samples observed using an optical microscope. The percentage of regenerated bone, number of osteoclasts and amount of inflammation was recorded. Statistical analysis was carried out using chi-square and Mann-Whitney U-tests.The results manifested a significant difference in the amount of bone formation, with the most being observed in the case group and the least in the negative-control group (p0.001). Significantly fewer osteoclasts were observed in the case group than in the other groups (p0.001). The amount of inflammation did not seem to differ within the case and control groups (p0.05).Adding pamidronate disodium to bovine-derived hydroxyapatite improves its osteoconductive and regenerative specifications. Further study should determine the systemic effects of a single local administration of these drugs, and their appropriate dose and type, with minimal risk.

Context: Regeneration of periodontium is one of the main goals of periodontal treatment. This may be achieved by differentiation of stem cells to periodontal tissue cells. Aims: This study sought to assess the differentiation of human periodontal ligament stem cells (PDLSCs) cultured in osteogenic medium supplemented with Emdogain or Simvastatin. Settings and Design: This is an experimental study. Materials and Methods: After teeth extraction, the PDL attached to the middle third of the root surface was removed. Cells were expanded in culture medium and used for osteogenic differentiation and added to the test materials (different combinations of the basic medium, dexamethasone [DEX], Simvastatin and Emdogain). Osteogenic differentiation was evaluated using Alizarin Red staining (ARS), alkaline phosphatase (ALP) activity and calcium content tests. Statistical Analysis Used: Statistical analysis was performed using SPSS version 17 software. Deliberation was done with 6 × 3 factorial (six groups × three periods). Then, the data were submitted to ANOVA, and the differences between the groups were compared using Tukey post-hoc test. Results: Quantitative analysis of ARS demonstrated that the frequency of mineralized nodule formation was the highest in the enamel matrix protein derivatives (EMD) + DEX group. The highest ALP activity on day 7 was in DEX + Simvastatin group. Calcium content was the lowest in the control group and the highest in EMD + DEX group at all tested time points. Conclusions: This study showed that 100 μg/ml Emdogain had a significant effect on osteogenic differentiation of human PDLSCs to osteoblasts and 10−8 M Simvastatin had an effect comparable to that of DEX.