Pathogenicity of Treponema denticola Wild-Type and Mutant Strain Tested by an Active Mode of Periodontal Infection Using Microinjection.

The available passive mode of periodontal infections in mice requires high efficiency of bacterial attachment and invasiveness and is not always suitable to test the pathogenicity of genetically engineered mutant strains. We developed an active mode of oral infection, using microinjection in the marginal gingiva of mice, to test the pathogenicity of a genetically engineered Treponema denticola mutant strain deficient in intermediate-like filaments, compared to the wild-type strain. This targeted mode of infection inoculates the bacterial strain to be tested directly at a lesion site (needle entry point) located at the future periodontal lesion site.

Aciduric microbiota and mutans streptococci in severe and recurrent severe early childhood caries.

Purpose: Severe early childhood caries (ECC) results from bacterial acid production in an acidic environment. The purpose of this study was to determine Streptococcus mutans, Streptococcus sobrinus, and acid-tolerant counts in severe early childhood caries.

Methods: Two- to 6-year-olds with severe-ECC (N=77) or who were caries-free (N=40) were examined.

Control of periodontal infections: a randomized controlled trial I. The primary outcome attachment gain and pocket depth reduction at treated sites.

Objective: To compare the treatment outcome of scaling and root planing (SRP) in combination with systemic antibiotics, local antibiotic therapy and/or periodontal surgery.

Material And Methods: One hundred and eighty-seven patients were assigned to eight groups treated by SRP plus none, one, two or three adjunctive treatments and monitored for 24 months in a randomized controlled clinical trial using a 2 × 2 × 2 factorial design. Systemic amoxicillin + metronidazole (SMA), local tetracycline delivery (LTC) and periodontal surgery (SURG) were evaluated as adjuncts.

Impact of periodontal therapy on the subgingival microbiota of severe periodontitis: comparison between good responders and individuals with refractory periodontitis using the human oral microbe identification microarray.

Background: This study compares the changes to the subgingival microbiota of individuals with "refractory" periodontitis (RP) or treatable periodontitis (good responders [GR]) before and after periodontal therapy by using the Human Oral Microbe Identification Microarray (HOMIM) analysis.

Methods: Individuals with chronic periodontitis were classified as RP (n = 17) based on mean attachment loss (AL) and/or >3 sites with AL ≥2.5 mm after scaling and root planing, surgery, and systemically administered amoxicillin and metronidazole or as GR (n = 30) based on mean attachment gain and no sites with AL ≥2.

Photodynamic effects of methylene blue-loaded polymeric nanoparticles on dental plaque bacteria.

Background And Objectives: Photodynamic therapy (PDT) is increasingly being explored for treatment of oral infections. Here, we investigate the effect of PDT on human dental plaque bacteria in vitro using methylene blue (MB)-loaded poly(lactic-co-glycolic) (PLGA) nanoparticles with a positive or negative charge and red light at 665 nm.

Study Design/materials And Methods: Dental plaque samples were obtained from 14 patients with chronic periodontitis.

Endodontic photodynamic therapy ex vivo.

Introduction: The objective of this study was to evaluate the antimicrobial effects of photodynamic therapy (PDT) on infected human teeth ex vivo.

Methods: Fifty-two freshly extracted teeth with pulpal necrosis and associated periradicular radiolucencies were obtained from 34 subjects. Twenty-six teeth with 49 canals received chemomechanical debridement (CMD) with 6% NaOCl, and 26 teeth with 52 canals received CMD plus PDT.

Inflammation and genetic risk indicators for early periodontitis in adults.

Background: This report is a further analysis of a study designed to determine clinical and microbial risk indicators for progressing periodontitis.

Methods: One hundred ninety subjects who were periodontally healthy or had early signs of periodontitis (age range: 20 to 40 years) were monitored clinically at 6-month intervals followed by supragingival cleaning. At each visit, gingival crevicular fluid (GCF) and blood were collected for determination of interleukin (IL)-1β content (in GCF) and IL-1 genotype (in blood).

Nanoparticle-based endodontic antimicrobial photodynamic therapy.

Objective: To study the in vitro effects of poly(lactic-co-glycolic acid) (PLGA) nanoparticles loaded with the photosensitizer methylene blue (MB) and light against Enterococcus faecalis (ATCC 29212).

Materials And Methods: The uptake and distribution of nanoparticles in E. faecalis in suspension was investigated by transmission electron microscopy (TEM) after incubation with PLGA complexed with colloidal gold particles for 2.

Relationships among gingival crevicular fluid biomarkers, clinical parameters of periodontal disease, and the subgingival microbiota.

Background: The objectives of this study were to measure levels of gingival crevicular fluid (GCF) biomarkers and subgingival bacterial species in periodontally healthy subjects and subjects with periodontitis to explore the relationships among these biomarkers, the subgingival microbiota, and the clinical parameters of periodontal disease.

Methods: Clinical periodontal parameters were measured at six sites per tooth in 20 subjects with periodontitis and 20 periodontally healthy subjects. GCF and subgingival plaque samples were obtained from the mesio-buccal aspect of every tooth.

Endodontic antimicrobial photodynamic therapy: safety assessment in mammalian cell cultures.

Objectives: The purpose of this study was to assess the in vitro synergistic effect of methylene blue (MB) and red light on human gingival fibroblasts and osteoblasts with parameters similar to those that may be applied in a clinical setting for endodontic disinfection.

Materials And Methods: Both cell types were sensitized with 50 microg/mL MB followed by exposure to red light at 665 nm for 5 minutes with an irradiance of 10, 20, and 40 mW/cm(2). After photodynamic therapy (PDT), cell viability and mitochondrial activity were evaluated by the neutral red and MTT assay, respectively.

Comparisons of subgingival microbial profiles of refractory periodontitis, severe periodontitis, and periodontal health using the human oral microbe identification microarray.

Background: This study compared the subgingival microbiota of subjects with refractory periodontitis (RP) to those in subjects with treatable periodontitis (GRs = good responders) or periodontal health (PH) using the Human Oral Microbe Identification Microarray (HOMIM).

Methods: At baseline, subgingival plaque samples were taken from 47 subjects with periodontitis and 20 individuals with PH and analyzed for the presence of 300 species by HOMIM. The subjects with periodontitis were classified as having RP (n = 17) based on mean attachment loss (AL) and/or more than three sites with AL >or=2.

Relationship between blood-spot insulin-like growth factor 1 levels and hand-wrist assessment of skeletal maturity.

Introduction: Accurate prediction of the timing of the pubertal growth spurt and the amount of remaining growth are factors that affect treatment decisions in orthodontics, orthognathic surgery, and dental implantology. For many years, medical and dental professionals have considered hand-wrist radiographs the method of choice for the assessment of skeletal maturity. Insulin-like growth factor 1 (IGF-1) mirrors growth hormone levels and is used by endocrinologists to diagnose growth hormone disturbances.

Assessing skeletal maturity by using blood spot insulin-like growth factor I (IGF-I) testing.

Introduction: Accurate determination of skeletal maturity and remaining growth is crucial to many orthodontic, orthognathic, and dental-implant timing decisions. Cervical vertebral stages and hand-wrist radiographs are currently used to identify peak mandibular bone growth. These are highly subjective techniques that not only involve radiographic exposure but also lack the ability to determine the intensity of the growth spurt and the end of growth.

Photodynamic treatment of endodontic polymicrobial infection in vitro.

We investigated the photodynamic effects of methylene blue on multispecies root canal biofilms comprising Actinomyces israelii, Fusobacterium nucleatum subspecies nucleatum, Porphyromonas gingivalis, and Prevotella intermedia in experimentally infected root canals of extracted human teeth in vitro. The 4 test microorganisms were detected in root canals by using DNA probes. Scanning electron microscopy showed the presence of biofilms in root canals before therapy.

Caries clinical trial of a remineralising toothpaste in radiation patients.

Objectives: The purpose of this study was to determine the efficacy and safety of a specially formulated remineralising toothpaste in controlling caries in a high-risk population: head and neck radiation patients.

Design: The study compared the performance of the remineralising toothpaste with a conventional fluoride dentifrice using double-blind randomisation.

Materials And Methods: Test products: The products compared contained equivalent quantities of fluoride (1100 p.

T cell response mediated by myeloid cell-derived IL-12 is responsible for Porphyromonas gingivalis-induced periodontitis in IL-10-deficient mice.

Periodontal disease is a chronic inflammatory disease in the oral cavity, which culminates in alveolar bone loss. Porphyromonas gingivalis is a consensus periodontal pathogen that has been implicated in adult forms of periodontitis. We previously demonstrated that IL-10-deficient mice exhibit a hyperinflammatory phenotype and are highly susceptible to P.

Photodynamic inactivation of Enterococcus faecalis in dental root canals in vitro.

Background And Objectives: We previously reported the use of a flexible fiber optic that uniformly distributed light in the root canal space for targeting bacteria after their sensitization with methylene blue (MB). In the present study, we investigated the photodynamic effects of MB on Enterococcus faecalis species in experimentally infected root canals of extracted teeth after their sensitization with a concentration of MB that exhibits reduced dark toxicity.

Study Design/materials And Methods: In a model of root canal infection, 64 root canal specimens were prepared from extracted, single-rooted teeth and inoculated with E.

Clinical characteristics and microbiota of progressing slight chronic periodontitis in adults.

Aim: This study sought clinical and microbial risk indicators for progressing slight periodontitis.

Material And Methods: One hundred and seventeen periodontally healthy or slight periodontitis adults (20-40 years) were monitored clinically at 6-month intervals followed by supragingival cleaning. Inter-proximal sites with >1.

Inhibition of tooth movement by osteoprotegerin vs. pamidronate under conditions of constant orthodontic force.

The undesired movement of anchor teeth, and relapse of previously moved teeth, are major clinical problems in orthodontics. Dental implants are increasingly used to preserve anchorage, but these are costly and require invasive surgical procedures. An alternative strategy for maintaining anchorage may be the use of biological inhibitors of osteoclastic bone resorption.

Tooth whitening: tooth color changes following treatment by peroxide and light.

Objective: This study examined the use of color measurement to determine tooth color in a study of bleaching with peroxide and light used separately and in combination. Two measurement protocols were evaluated for their ability to reveal differences between treatments and confirm tooth shade evaluations.

Methodology: Before and after treatment, 43 subjects were evaluated for tooth color using a shade guide and a chromameter.

Clinical and other risk indicators for early periodontitis in adults.

Background: Periodontal diseases affect over half the adults in the U.S., disproportionately affecting minority populations.

The interleukin-10 knockout mouse is highly susceptible to Porphyromonas gingivalis-induced alveolar bone loss.

Objective: Interleukin-10 is an anti-inflammatory cytokine that reduces periapical bone loss, but its role in periodontal bone loss is unclear. In the present study, we tested the hypothesis that endogenous interleukin-10 is a potent suppressor of Porphyromonas gingivalis-induced alveolar bone loss in vivo.

Methods: Interleukin-10 knockout (-/-) and wild-type mice were inoculated intraorally with P.

Light augments tooth whitening with peroxide.

Background: The authors tested the adjunctive use of light with a 15 percent peroxide gel as a single-visit, in-office tooth whitening system.

Methods: Subject (N = 87) with stained (> shade D4, Vita Zahnfabrik, Bad Säckingen, Germany) anterior teeth were randomly assigned to test (peroxide and light), peroxide control (peroxide gel) or light control (placebo gel and light) groups and were treated for one hour. The researchers evaluated tooth shade, color and subject response at baseline and posttreatment and at three and six months posttreatment.

A mouse model of human oral-esophageal cancer.

Squamous cancers of the oral cavity and esophagus are common worldwide, but no good genetically based animal model exists. A number of environmental factors as well as genetic alterations have been identified in these cancers, yet the specific combination of genetic events required for cancer progression remains unknown. The Epstein-Barr virus ED-L2 promoter (L2) can be used to target genes in a specific fashion to the oral-esophageal squamous epithelium.

Enhanced neutrophil emigration and Porphyromonas gingivalis reduction following PGG-glucan treatment of mice.

Periodontal disease is the consequence of a mixed Gram-negative infection in the gingival sulcus and has been associated with deficits in the neutrophil response. A novel, and heretofore untested, alternative approach to therapy is the use of biological-response modulators that enhance the neutrophil response. Poly-beta1-6-glucotriosyl-beta1-3-glucopyranose glucan (PGG-glucan) is an immunomodulator, derived from yeast, which specifically enhances neutrophil priming, phagocytosis and bacterial killing while failing to induce inflammatory cytokine expression.