Inhibitory impact of a mesoporous silica nanoparticle-based drug delivery system on Porphyromonas gingivalis-induced bone resorption.

Controlling and reducing plaque formation plays a pivotal role in preventing and treating periodontal disease, often utilizing antibacterial drugs to enhance therapeutic outcomes. Mesoporous silica nanoparticles (MSN), an FDA-approved inorganic nanomaterial, possess robust physical and chemical properties, such as adjustable pore size and pore capacity, easy surface modification, and high biosafety. Numerous studies have exploited MSN to regulate drug release and facilitate targeted delivery.

Type 1-3 Canal Configuration in the Buccal Root of a Maxillary Second Molar.

Objectives: A major challenge in root canal treatment is the complex and variable root canal system. There are several methods of classification of root canal systems. Herein, we report a case of a maxillary second molar, the root canal system of which could not be classified according to any of the previous methods.

The Combinations Chitosan-PamCSK and Chitosan-Monophosphoryl Lipid A: Promising Immune-Enhancing Adjuvants for Anticaries Vaccine PAc.

We previously demonstrated that recombinant protein PAc could be administered as an anticaries vaccine. However, the relatively weak immunogenicity of PAc limits its application. In the present study, we investigated the effect of two adjuvant combinations of chitosan plus PamCSK (chitosan-PamCSK) and of chitosan plus monophosphoryl lipid A (chitosan-MPL) in the immune responses to the PAc protein and PAc-chitosan-PamCSK or PAc-chitosan-MPL promoted significantly higher PAc-specific antibody titers in serum and saliva, inhibited colonization onto the tooth surfaces, and endowed better protection effect with significantly less caries activities than PAc alone.

Regenerative Endodontic Treatment of a Maxillary Mature Premolar.

Regenerative endodontic treatment was performed on a mature maxillary premolar diagnosed as chronic pulpitis. The root canals were chemomechanically prepared and placed intracanal medicaments at the first appointment. Then 2 weeks later, a blood clot was created in the canals, over which mineral trioxide aggregate was placed.

Phenotype and Function of Myeloid-Derived Suppressor Cells Induced by Porphyromonas gingivalis Infection.

, a major etiologic agent of periodontitis, has been reported to induce the expansion of myeloid-derived suppressor cells (MDSC); however, little is known regarding the subpopulations of MDSC expanded by infection. Flow cytometry was used to evaluate bone marrow and spleen cells from mice infected with and controls for surface expression of CD11b, Ly6G, and Ly6C. To characterize the phenotype of MDSC subpopulations induced by infection, cells were sorted based on the differential expression of Ly6G and Ly6C.

Inhibitory effect of 1,25-dihydroxyvitamin D on Porphyromonas gingivalis-induced inflammation and bone resorption in vivo.

Objective: To investigate whether intragastric administration of 1,25-dihydroxyvitamin D (1,25(OH)D) could inhibit the bone resorption and inflammation in a mouse calvarial model infected by Porphyromonas gingivalis (P. gingivalis).

Design: Live P.

CCL17 combined with CCL19 as a nasal adjuvant enhances the immunogenicity of an anti-caries DNA vaccine in rodents.

Aim: CCL19 and its receptor CCR7 are essential molecules for facilitating the trafficking of mature dendritic cells (DCs) and helping to establish a microenvironment in lymphoid tissues to initiate primary immune responses, whereas CCL17 is required in the CCR7-CCL19-dependent migration of DCs. In this study we examined whether co-administration of CCL17 and CCL19 could enhance the immunogenicity of an anti-caries DNA vaccine, pCIA-P, in rodents.

Methods: Plasmids encoding CCL17 (pCCL17/VAX) and CCL19 (pCCL19/VAX) were constructed.

Effects of 1,25-dihydroxyvitamin D on Macrophage Cytokine Secretion Stimulated by Porphyromonas gingivalis.

Vitamin D is known to be closely associated with periodontitis; however, its exact mechanisms remain to be clarified. The present study aimed to investigate the influence of 1,25-dihydroxyvitamin D (1,25(OH)D) on Porphyromonas gingivalis (Pg)-stimulated cytokine production and the involved signaling pathways in macrophages. The main observation was that 1,25(OH)D inhibited Pg-induced interleukin (IL)-6 cytokine expression but up-regulated the expression of anti-inflammatory cytokine IL-10.

IL-1R/TLR2 through MyD88 Divergently Modulates Osteoclastogenesis through Regulation of Nuclear Factor of Activated T Cells c1 (NFATc1) and B Lymphocyte-induced Maturation Protein-1 (Blimp1).

Toll-like receptors (TLR) and the receptor for interleukin-1 (IL-1R) signaling play an important role in bacteria-mediated bone loss diseases including periodontitis, rheumatoid arthritis, and osteomyelitis. Recent studies have shown that TLR ligands inhibit the receptor activator of NF-κB ligand (RANKL)-induced osteoclast differentiation from un-committed osteoclast precursors, whereas IL-1 potentiates RANKL-induced osteoclast formation. However, IL-1R and TLR belong to the same IL-1R/TLR superfamily, and activate similar intracellular signaling pathways.

Direct Pulp Capping with Calcium Hydroxide or Mineral Trioxide Aggregate: A Meta-analysis.

Introduction: The purpose of this study was to compare the effectiveness of mineral trioxide aggregate (MTA) and calcium hydroxide (CH) as pulp capping materials in humans by means of a meta-analysis.

Methods: The PubMed, Cochrane Library, Embase, and Web of Knowledge databases were used in the literature search from their establishment date until December 7, 2014. Studies that met the inclusion criteria were accepted, and necessary information was extracted by 2 authors independently using a standardized form.

Extensive description and comparison of human supra-gingival microbiome in root caries and health.

Knowledge of the polymicrobial etiology of root caries is limited. To conduct a comprehensive research study on root caries, we utilized 454-pyrosequencing of 16S rRNA gene libraries and quantitative PCR to compare supra-gingival bacterial communities from healthy sites and carious sites of 21 patients with root caries (Patient-controls and Patient-cases) and the sites of 21 healthy individuals (Healthy-controls) from two nursing homes. Healthy-controls and Patient-cases showed no significant differences in terms of biomass, species richness, and species diversity.

Intranasal co-delivery of IL-6 gene enhances the immunogenicity of anti-caries DNA vaccine.

Aim: To investigate the effects of co-delivering IL-6 expressing plasmid pCI-IL-6 on the immunogenicity of the anti-caries DNA vaccine pCIA-P, which encodes the surface protein antigen PAc of Streptococcus mutans.

Methods: Plasmid pCI-IL-6 was constructed by inserting the murine IL-6 gene into the pCI vector. Expression of IL-6 in vitro was assessed using Western blot analysis.

[Application of case-based learning in clinical internship teaching of conservative dentistry and endodontics].

Purpose: To investigate the education effect of case-based learning (CBL) pattern on clinical internship of conservative dentistry and endodontics.

Methods: Forty-one undergraduates were randomly assigned into CBL group and traditional teaching group. After clinical internship in the department of conservative dentistry and endodontics for 11 weeks, each student in the 2 groups underwent comprehensive examinations including medical record writing, case analysis, academic knowledge, professional skills and the ability of winning the trust of the patients.

A new gcrR-deficient Streptococcus mutans mutant for replacement therapy of dental caries.

Background: gcrR gene acts as a negative regulator related to sucrose-dependent adherence in S. mutans. It is constructive to test the potential capacity of mutans with gcrR gene deficient in bacteria replacement therapy.

Role of mTOR downstream effector signaling molecules in Francisella tularensis internalization by murine macrophages.

Francisella tularensis is an infectious, gram-negative, intracellular microorganism, and the cause of tularemia. Invasion of host cells by intracellular pathogens like Francisella is initiated by their interaction with different host cell membrane receptors and the rapid phosphorylation of different downstream signaling molecules. PI3K and Syk have been shown to be involved in F.

Co-delivery of ccl19 gene enhances anti-caries DNA vaccine pCIA-P immunogenicity in mice by increasing dendritic cell migration to secondary lymphoid tissues.

Aim: To investigate how co-delivery of the gene encoding C-C chemokine ligand-19 (CCL-19) affected the systemic immune responses to an anti-caries DNA vaccine pCIA-P in mice.

Methods: Plasmid encoding CCL19-GFP fusion protein (pCCL19/GFP) was constructed by inserting murine ccl19 gene into GFP-expressing vector pAcGFP1-N1. Chemotactic effect of the fusion protein on murine dendritic cells (DCs) was assessed in vitro and in vivo using transwell and flow cytometric analysis, respectively.

Anti-caries DNA vaccine-induced secretory immunoglobulin A antibodies inhibit formation of Streptococcus mutans biofilms in vitro.

Aim: To investigate the effects of anti-caries DNA vaccine-induced salivary secretory immunoglobulin A (S-IgA) antibodies on Streptococcus mutans (S. mutans) adherence and biofilms formation in vitro.

Methods: Adult female Wistar rats were intranasally immunized with the anti-caries DNA vaccine pGJA-P/VAX.

A mucosal subunit vaccine protects against lethal respiratory infection with Francisella tularensis LVS.

Francisella tularensis (FT) is a highly virulent pathogen for humans and other mammals. Severe morbidity and mortality is associated with respiratory FT infection and there are concerns about intentional dissemination of this organism. Therefore, FT has been designated a category A biothreat agent and there is a growing interest in the development of a protective vaccine.

Contribution of a Streptococcus mutans antigen expressed by a Salmonella vector vaccine in dendritic cell activation.

A Salmonella vector vaccine expressing the saliva-binding region (SBR) of the adhesin AgI/II of Streptococcus mutans has been shown to induce a mixed Th1/Th2 anti-SBR immune response in mice and to require Toll-like receptor 2 (TLR2), TLR4, and MyD88 signaling for the induction of mucosal anti-SBR antibody responses. Since dendritic cells (DC) are critical in innate and adaptive immunity, the present study assessed the role of SBR expression by the vector vaccine in DC activation. Bone marrow-derived DC from wild-type and TLR2, TLR4, and MyD88 knockout mice were stimulated with Salmonella vector BRD509, the SBR-expressing Salmonella vector vaccine BRD509(pSBRT7), or SBR protein, and the DC responses to different stimuli were compared by assessing costimulatory molecule expression, cytokine production, and signaling pathways.

TLR2-dependent modulation of osteoclastogenesis by Porphyromonas gingivalis through differential induction of NFATc1 and NF-kappaB.

Osteolytic diseases, including rheumatoid arthritis, osteomyelitis, and periodontitis, are usually associated with bacterial infections. However, the precise mechanisms by which bacteria induce bone loss still remain unclear. Evidence exists that Toll-like receptor (TLR) signaling regulates both inflammation and bone metabolism and that the receptor activator of NF-κB ligand (RANKL) and its receptor RANK are the key regulators for bone remodeling and for the activation of osteoclasts.

A targeted fimA DNA vaccine prevents alveolar bone loss in mice after intra-nasal administration.

Aim: To construct a dendritic cell (DC)-targeted DNA vaccine against FimA of Porphyromonas gingivalis and evaluate the immunogenicity and protection in mice.

Materials And Methods: A targeted DNA plasmid pCTLA4-FimA, which encodes the signal peptide and extracellular regions of mouse cytotoxic T lymphocyte-associated antigen 4 (CTLA4), the hinge and Fc regions of human Igγ1 and FimA of P. gingivalis, was constructed.

Human papillomavirus as an independent predictor in oral squamous cell cancer.

Aim: There is an increasing evidence for the role of high risk human papillomavirus (HPV) in the pathogenesis of oral squamous cell carcinoma (OSCC). The purpose of this study is to evaluate the relevance of HPV infection to the survival and prognosis of OSCC.

Methodology: Fifty-two patients with OSCC were followed from 4 to 88 months with a median of 50.

[Protective efficacy of a new fusion anti-caries DNA vaccine encoding antigens of both Streptococcus mutans and Streptococcus sobrinus].

Objective: To construct a new fusion anti-caries DNA vaccine pGJGAC/VAX encoding antigens of both S. mutans and S. sobrinus so as to enhance the protective effect of DNA vaccine against S.

A new strategy for the replacement therapy of dental caries.

The rationale of bacterial replacement therapy against dental caries is that relatively avirulent strains of Mutans Streptococi (MS) are most likely to occupy the same ecological niche in plaque as their more cariogenic counterparts. As known, lactate dehydrogenase (LDH) deficiency has been proposed as one aspect of a strategy to construct an effector strain because LDH-deficient mutants could affect acid production by MS so as to reduce their cariogenicity. Glucan-binding lectin (GBL) plays a very important role in the formation of dental plaque biomembrane and the adherence of S.

Protective efficacy of two new anti-caries DNA vaccines.

As we know, the catalytic region of glucosyltransferases (GTFs) is a key region responsible for sucrose-dependent adherence of cariogenic bacteria to teeth. In this study, we evaluate the potential of the catalytic region to enhance the immunogenicity of the anti-caries DNA vaccine. We construct two new anti-caries DNA plasmids pGJGAC/VAX and pGJGA-5C/VAX by cloning different styles of the catalytic regions of GTFs into the previous plasmid pGJA-P/VAX.