Porphyromonas gingivalis evasion of autophagy and intracellular killing by human myeloid dendritic cells involves DC-SIGN-TLR2 crosstalk.

Signaling via pattern recognition receptors (PRRs) expressed on professional antigen presenting cells, such as dendritic cells (DCs), is crucial to the fate of engulfed microbes. Among the many PRRs expressed by DCs are Toll-like receptors (TLRs) and C-type lectins such as DC-SIGN. DC-SIGN is targeted by several major human pathogens for immune-evasion, although its role in intracellular routing of pathogens to autophagosomes is poorly understood. Here we examined the role of DC-SIGN and TLRs in evasion of autophagy and survival of Porphyromonas gingivalis in human monocyte-derived DCs (MoDCs). We employed a panel of P. gingivalis isogenic fimbriae deficient strains with defined defects in Mfa-1 fimbriae, a DC-SIGN ligand, and FimA fimbriae, a TLR2 agonist. Our results show that DC-SIGN dependent uptake of Mfa1+P. gingivalis strains by MoDCs resulted in lower intracellular killing and higher intracellular content of P. gingivalis. Moreover, Mfa1+P. gingivalis was mostly contained within single membrane vesicles, where it survived intracellularly. Survival was decreased by activation of TLR2 and/or autophagy. Mfa1+P. gingivalis strain did not induce significant levels of Rab5, LC3-II, and LAMP1. In contrast, P. gingivalis uptake through a DC-SIGN independent manner was associated with early endosomal routing through Rab5, increased LC3-II and LAMP-1, as well as the formation of double membrane intracellular phagophores, a characteristic feature of autophagy. These results suggest that selective engagement of DC-SIGN by Mfa-1+P. gingivalis promotes evasion of antibacterial autophagy and lysosome fusion, resulting in intracellular persistence in myeloid DCs; however TLR2 activation can overcome autophagy evasion and pathogen persistence in DCs.

Student perspectives on sexual health: implications for interprofessional education.

Interprofessional collaboration requires that health professionals think holistically about presenting concerns, particularly for multimodal problems like sexual dysfunction. However, health professions students appear to receive relatively little sexual health education, and generally none is offered on an interprofessional basis. To assess current degree of interprofessional thinking in sexual health care, 472 health professions students in Georgia, United States, were presented with a sexual dysfunction vignette and asked to rate the relevance of, and their familiarity with, interventions offered by several professionals. They also were asked to identify the most likely cause of the sexual dysfunction. Students rated relevance and familiarity with interventions as highest for physicians and lowest for dentists, with higher ratings of nurses by nursing students. More advanced students reported greater familiarity with mental health, physician, and physical therapy interventions. Finally, nursing students were less likely to attribute the dysfunction to a physical cause. These findings indicate that students may prioritize biomedical approaches in their initial assessment and may need additional supports to consider the spectrum of biopsychosocial factors contributing to sexual functioning. To encourage interprofessional critical thinking and prepare students for interprofessional care, sexual health curricula may be improved with the inclusion of interprofessional training. Specific recommendations for curriculum development are offered.

Effect of curing mode on the polymerization characteristics of dual-cured resin cement systems.

OBJECTIVES: To evaluate the effects of different curing conditions on the degree of conversion (DC) of dual-cured cementing systems [combination of bonding agent (BA) and resin cement (RC)] using infrared spectroscopy. METHODS: Four fourth generation products [Scotchbond Multipurpose Plus/RelyX (3M ESPE), Optibond/Nexus 2 (Kerr), All Bond2/Duolink (Bisco), and Bond-It!/Lute-It! (Pentron)], and three fifth generation materials [Bond1/Lute-It! (Pentron), Prime&Bond NT Dual-Cure/Calibra (Dentsply), and Optibond Solo Dual Cure/Nexus 2 (Kerr)] were applied to the surface of a horizontal attenuated-total-reflectance unit, and were polymerized using one of four conditions: self-cure (SC), direct light exposure through glass slide (DLE, XL3000/3M ESPE) or through pre-cured resin discs (shades A2;A4/2mm thick/Z250/3M ESPE). Infrared spectra of the uncured cementing systems were recorded immediately after application to the ATR, after the system was light-cured or left to self-cure, and spectra were obtained 5 and 10 min later. DC was calculated using standard techniques of observing changes in aliphatic-to-aromatic peak ratios pre- and post-curing. Data (n=5) were analyzed by two-way repeated measures ANOVA and Tukey's test (p=0.05). RESULTS: Changes in aliphatic-to-aromatic peak ratios before and after placing RC onto the BA demonstrated that a combined layer was created. All groups exhibited higher DC after 10 min than after 5 min, except the DLE group of Bond-it!/Lute-it!. No significant differences in DC were observed among light-activated groups regardless of the resin disc shade in three of the four fourth generation cementing systems. The SC groups exhibited lower DC than the DLE groups for both fourth and fifth generation products either after 5 or 10 min. CONCLUSION: The chemistry of the bonding interface changed when RCs were applied to uncured BAs. The presence of an indirect restoration can decrease the DC of some cementing systems and the self-curing mode leads to lower DC than the light-activating one.

Parental Smoking Cessation: Impacting Children's Tobacco Smoke Exposure in the Home.

OBJECTIVES: There is no safe or risk-free level of tobacco use or tobacco smoke exposure. In this randomized controlled trial, we tested a tobacco control intervention in families and specifically evaluated a tailored cessation intervention for the parents and/or caregivers (Ps/Cs) who were smokers while their children were simultaneously enrolled in tobacco prevention. METHODS: Ps/Cs and children were recruited from 14 elementary schools across rural and urban settings. Approximately one-fourth (24.3%; n = 110) of the total Ps/Cs enrolled in the randomized controlled trial (n = 453) were smokers, predominantly women (80.9%), with a mean age of 37.7 years. (SD 12.2); 62.7% were African American, 44% had less than a high school education, and 58% earned <$20 000 annually. P/C smokers were offered a tailored cessation intervention in years 1 and 2. Self-report smoking status and saliva cotinine were obtained at baseline, the end of treatment (EOT) and/or year 2, and in the year 4 follow-up. RESULTS: Ps/Cs in the intervention group showed a larger increase in self-reported smoking abstinence over time (EOT: 6.5% [SE = 5.7%]; year 4: 40.6% [SE = 5.7%]) than the control group (EOT: 0.0% [SE = 6.5%]; year 4: 13.2% [SE = 6.4%]; F = 4.82; P = .0306). For cotinine, the intervention group showed a decrease from baseline (239.9 [SE = 1.3]) to EOT 99.3 [SE = 1.4]) and then maintenance through year 4 (109.6 [SE = 1.4]), whereas the control group showed increases from baseline (221.1 [SE = 1.4]) to EOT (239.0 [SE = 1.4]) to year 4 (325.8 [SE = 14]; F = 5.72; P = .0039). CONCLUSIONS: This study provides evidence that tailored cessation offered to Ps/Cs in their children's schools during their children's enrollment in tobacco prevention may contribute to more robust success in P/C cessation and a reduction of tobacco smoke exposure in children.

Up-regulation of SIBLING proteins and correlation with cognate MMP expression in oral cancer.

Various combinations of the SIBLING family of proteins have been found to be up-regulated in many human cancers and have been linked to different stages of tumor progression, including metastasis. Bone sialoprotein (BSP), osteopontin (OPN) and dentin matrix protein 1 (DMP1) specifically bind and activate MMP-2, MMP-3, and MMP-9, respectively. These proteases have also been shown to play important roles in oral squamous cell carcinoma (OSCC) invasion and metastasis. However, with the exception of OPN, there are no reports on the expression of the family of five SIBLING proteins in OSCC. This study examines the expression patterns of the SIBLING family (and MMP partners when known) in OSCC, correlating expression to outcome variables. Archived paraffin sections of 87 cases of primary OSCC were screened by immunohistochemistry for the SIBLINGs and their MMP partners. Three SIBLINGs (BSP, DSPP, and OPN), were expressed in OSCC, while DMP1 and MEPE expression were never observed. Furthermore, BSP and OPN were always expressed with their known MMP partners, MMP-2 and MMP-3, respectively. Poorly differentiated tumors exhibited reduced or no immunoreactivity for BSP and OPN but increased immunoreactivity for DSPP. Seventy eight (90%) cases were positive for BSP and DSPP, while 79 cases (91%) were positive for OPN. Overall, 91% of the cases were positive for at least one SIBLING. There were no correlations between SIBLING expression and tumor size ("T"; of the Union Internationale Contre le Cancer [UICC]-TNM classification for OSCC), and between SIBLING expression and lymph node spread for the T1/T2 tumors. The levels of DSPP expression for floor of mouth and retromolar region tumors were higher than for tongue tumors. Statistically significant correlations were, however, found between the expression levels of BSP and MMP-2 (p<0.0001), BSP and MMP-3 (p<0.0001), and OPN and MMP-3 (p<0.0024). We conclude that BSP, DSPP, and OPN are highly up-regulated in OSCC. While the production of these SIBLINGs is independent of T, they correlate with oral location of tumor, cognate MMP expression, and for DSPP, the degree of tumor differentiation.

Infiltration/evaporation-induced shrinkage of demineralized dentin by solvated model adhesives.

During dentin bonding, solvated adhesive comonomers are applied to water-saturated decalcified dentin matrices. When alcohol-solvated hydrophilic or hydrophobic methacrylate monomers are applied, they chemically remove water and cause matrix shrinkage during comonomer infiltration. Evaporation of solvent induces further shrinkage. The purpose of this work was to compare the shrinkage of water-saturated dentin matrices infiltrated with ethanol- or methanol-solvated 2-hydroxyethyl methacrylate (HEMA), 2,2-bis[4(2-hydroxy-3-methacryloyloxy-propyloxy)-phenyl] propane (BisGMA), or triethyleneglycol dimethacrylate (TEGDMA) at 90/10, 70/30, 50/50, and 30/70 mass fraction % alcohol/monomer before and after evaporation of alcohol. Thin (ca 0.2 mm) disks of human mid-coronal dentin were demineralized and placed in a well beneath the contact probe of a linear variable differential transformer (LVDT). The height of the matrix was measured before and after random application of one of the twelve alcohol/monomer mixtures. Matrix height was measured during infiltration and during solvent evaporation. Between trials, residual monomer was extracted using ethanol. These studies were repeated on specimens in which 100% alcohol was used to substitute for water in the matrix. Both studies revealed that matrices shrink 30-50% but that pretreatment of matrices with alcohol prevents BisGMA phase separations from occurring. Wet bonding with ethanol instead of water permits infiltration of relatively hydrophobic alcohol/monomers.

Age and gender differences in the use of behavior management techniques by pediatric dentists.

PURPOSE: This study evaluated differences in the use of behavior management techniques among older and younger male and female pediatric dentists. METHODS: We surveyed all active members of the American Academy of Pediatric Dentistry residing in the U.S. and Canada. Responses were received from 2467 (59%). The survey contained items on age, gender, and use of behavior management techniques. RESULTS: Males respondents outnumbered females 2:1. Age categories were dichotomized as < 46 and > or = 46 years. Females constituted 53% of the younger group and 14% of the older group. Four gender/age categories were used. A minority indicated that they used hand-over-mouth and active immobilization of sedated patients. No significant differences by groups were seen for use of most basic behavior management techniques. Significant differences by gender/age distribution were seen for the use of non-verbal communication and advanced techniques. Most differences in anticipated changes in technique use were age-related. Most favored parental presence in the operatory, though older males were significantly less likely to allow parental presence for some procedures. CONCLUSIONS: Some statistically significant differences in the use of behavior management techniques exist between older and younger male and female pediatric dentists. Overall, however, the 4 gender/age groups report similar frequencies of use of the techniques surveyed in this study.

Net expansion of dried demineralized dentin matrix produced by monomer/alcohol saturation and solvent evaporation.

The purpose of this work was to determine if nonaqueous methacrylate monomer/alcohol mixtures could expand dried collapsed demineralized dentin matrix. Thin disks (ca. 200 microm) of human dentin were demineralized and placed in wells beneath contact probes of linear variable differential transformers. The probes were placed on water-saturated expanded matrices to record the shrinkage associated with drying. Monomer mixtures containing hydroxyethyl methacrylate, 2,2-bis[4-(2-hydroxy-3 methacryloyloxy)propoxyphenyl] propane, or triethyleneglycol dimethacrylate were mixed with methanol or ethanol at alcohol/monomer mass fraction % of 90/10, 70/30, 50/50, or 30/70. They were randomly applied to the dried matrices to determine the rate and magnitude of expansion; then shrinkage was recorded during evaporation of the alcohols. The results indicated that matrix expansion was positively correlated with the Hoy's solubility parameters for hydrogen bonding forces (delta(h)) of the monomer/solvent mixtures (p < 0.001). Expansions were more rapid with methanol-containing than with ethanol-containing monomer mixtures. For the test solutions, triethyleneglycol dimethacrylate-containing mixtures produced the slowest rate of matrix expansion and hydroxyethyl methacrylate-containing mixtures the most rapid expansion. When the solvents were evaporated, the matrix shrank in proportion to the solvent content and the delta(h) of the monomer-solvent mixtures. The results indicate that expansion of dried, collapsed dentin matrices requires that the delta(h) of the mixtures be larger than 17 (J/cm(3))(1/2). The greater the delta(h) of the monomer solutions, the greater the rate and extent of expansion.

Improving the performance of EndoREZ root canal sealer with a dual-cured two-step self-etch adhesive. II. Apical and coronal seal.

This study tested the hypothesis that the seal of EndoREZ may be improved with an adhesive-modified technique. Instrumented single-rooted teeth were filled with: (a) Warm vertical compaction with AH Plus (control); (b). EndoREZ with master cones and passive application of accessory cones; (c) Application of Clearfil Liner Bond 2V before EndoREZ and gutta-percha condensation. Leakage was assessed by fluid filtration at 10 psi before root resection and after 3 to 12 mm apical resections. Statistical analyses revealed significant differences in filling technique and resection lengths. EndoREZ exhibited significantly higher overall leakage, while no difference was found between AH Plus and the adhesive-modified EndoRez technique. Apical resection of EndoREZ to 12 mm exhibited more leakage than all other interactions, but was not significantly different from the same material resected to 9 mm. Although EndoREZ exhibited an acceptable apical seal, its coronal seal may be improved with the use of a dual-cured self-etch adhesive.

Penetration of fluids into periodontal pockets using a powered toothbrush/irrigator device.

UNLABELLED: This study was a single-blind, randomized, controlled clinical trial. The researchers evaluated a powered brush/irrigating device (HydraBrush Oral Health System; OHS) for its safety and ability to deliver a solution to the bottom of 5-6 mm pockets, compared to rinsing alone with a solution following brushing with a powered toothbrush (Sonicare Elite 7800; SE). An evaluation technique to measure the quantity and quality of solution able to enter the pocket was also introduced in this project. METHODS: Subjects were randomized in one of two-groups: brush plus simultaneous irrigation (OHS) versus brush plus rinsing (SE). Subjects used their devices at home for two weeks. At the measurement visit, subjects used the OHS to irrigate and brush simultaneously for 1 minute (30 seconds per each side of the mouth) with a 0.01% erythrosine disclosing solution in 10 oz of distilled water. Control subjects brushed for 2 minutes with a SE followed by a 1 minute rinse with an identical disclosing solution. A blinded evaluator collected six samples of approximately of 1 microL of sucular fluid from six 5-6 mm evaluation sites. This was accomplished by inserting a microcapillary tip with a 20 microL micropipette in the sulcus. Two-group repeated measures ANOVA was used to examine differences in two measures of the disclosing solution between OHS and SE subjects; the spectrometer reading of the disclosing solutions, and by visual inspection of the samples (positive/negative) to determine the presence or absence of solution in the samples. Subjects' diaries were collected. Bleeding and discomfort during the evaluation period was reported. RESULTS: Visually, OHS had a significantly greater proportion of solution taken from the base of 5-6 mm sites than the SE (p=0.0001). However, there was no statistical difference between the two groups (p=.1359) in the spectrophotometer readings. CONCLUSION: The experimental device is more efficient in delivering a solution to the base of 5-6 mm pockets than rinsing following use of a control powered toothbrush. Both devices have demonstrated they are safe and well accepted by patients. The technique developed provides a useful method for quantitative and qualitative studies of solutions from the base of periodontal pockets.

Effects of multiple coatings of two all-in-one adhesives on dentin bonding.

PURPOSE: Simple changes to bonding technique can improve resin-dentin bond strengths. The objective of this study was to evaluate the effects of multiple coatings of two all-in-one adhesive resins on both microtensile bond strength (microTBS) and nanoleakage. MATERIALS AND METHODS: The mid-coronal occlusal dentin of extracted human molars was used. Two all-in-one adhesives--iBond (Heraeus Kulzer) and Xeno III (Caulk Dentsply)--were applied to 320-grit abraded dentin surfaces. In groups 1 and 3 during bonding, monomer application and solvent evaporation were done 1, 2, 3, 4 or 5 times on the dentin surface before light curing. In groups 2 and 4 after light curing the first layer, the adhesive was re-applied, the solvent evaporated, and the layer light cured. This was repeated from 2 to 5 times, followed by creation of composite buildups. After 24 h storage in 37 degrees C water, the teeth were sectioned perpendicular to the adhesive interface to produce multiple beams of composite-bonded dentin, approximately 0.9 mm2 in area. These were tested to failure in tension. Data were evaluated by three-way ANOVA (material vs coatings vs light curing) followed by multiple comparisons at alpha = 0.05. Additionally, nanoleakage of silver uptake and adhesive layer thickness were evaluated using transmission electron microscopy (TEM). RESULTS: The results indicated that bond strengths increased with the number of coatings (p < 0.0001) with both adhesives, up to 3 layers, especially if each layer was light cured. Nanoleakage of silver tended to decrease with each coat in both adhesive systems. CONCLUSION: By simply applying more coats of adhesive, the strength and quality of dentin adhesion can be improved.

In vitro evaporative vs. convective water flux across human dentin before and after conditioning and placement of glass-ionomer cements.

PURPOSE: To assess the convective and evaporative fluid movement across glass-ionomer treated dentin. METHODS: Crown segments made from extracted human teeth, were divided into two groups of 14 teeth each. Each segment was cemented onto a plexiglass slab penetrated by a stainless steel tube, permitting filling of the pulp chamber with water. This set-up was attached to a device that measured fluid movement through the dentin in the crown segment. The experimental design involved repeated measurements of convective and evaporative fluid movements in each of the following conditions: smear layer-covered dentin, conditioned dentin, dentin after placement of one of two glass-ionomers (Fuji IX or Ketac-Molar), with and without a protective coating. The same water fluxes were remeasured after storage of the samples for 24 hours in distilled water. RESULTS: Statistical analysis of the results using ANOVA indicated a significant difference between the two measured water fluxes (P < 0.001). There was also a significant difference between the two materials (P < 0.001), with Ketac-Molar allowing higher permeability than Fuji IX. Conditioning the dentin surface with polyacrylic acid increased the convective water flux (P < 0.05) but did not change the evaporative water flux. Placement of the glass-ionomer material did not change the rate of spontaneous evaporation of water from the dentin, but the application of a coating agent reduced the evaporative water loss. These values were not significantly different when the specimens were stored for 24 hours.

Survey of behavior management teaching in predoctoral pediatric dentistry programs.

PURPOSE: The purpose of this study was to survey directors of predoctoral pediatric dentistry programs regarding the teaching of behavior management techniques. METHODS: Surveys were mailed to all 56 dental schools in the United States. Follow-up mailings were sent to nonrespondents. The survey contained items on program demographics and the program's teaching of communicative and pharmacologic techniques. Information was also obtained on informed consent and parental presence in the operatory. RESULTS: Surveys were returned by 48 schools. Two schools declined to respond because they had not yet accepted or graduated students. The final response rate was 89%. The mean (+/-SD) percentage of total didactic time devoted to behavior management was 12% (+/-6). Communicative techniques were taught as "acceptable" by 96% to 100% of programs, with the exception of the hand-over-mouth exercise (HOME). HOME was taught as "unacceptable" by 62% of programs. Active and passive immobilization of sedated and nonsedated children was taught as "acceptable" by 69% to 85% of programs. Sixty-seven percent to 98% of programs taught that pharmacologic techniques (nitrous oxide, conscious sedation, general anesthesia) are "acceptable." There was little evidence that the teaching of behavior management techniques had changed over the previous 5 years, nor that they were likely to change in the near future. Parental presence in the operatory was common for some procedures, particularly among younger children. CONCLUSIONS: Predoctoral programs teach as acceptable communicative and pharmacologic management techniques, with the exception of HOME. Predoctoral program directors report they are not likely to increase the amount of curricular time devoted to behavior management in the near future.

A survey of members of the American Academy of Pediatric Dentistry on their use of behavior management techniques.

PURPOSE: The objective of this study was to survey members of the American Academy of Pediatric Dentistry (AAPD) regarding their use of behavior management techniques. METHODS: Surveys were mailed to 4,180 members, with a follow-up mailing to nonrespondents 2 months later. The survey contained items on demographic variables and use (current, past, and future) of communicative and pharmacologic techniques. Information was also obtained on informed consent, parental presence in the operatory, and parenting styles. RESULTS: Survey response was 66%. Communicative techniques are widely used, with the exception of the hand-over-mouth exercise (HOME). Immobilization for sedated and nonsedated children and pharmacologic techniques are used by a majority or near majority of respondents. Little change was reported in technique use over time, except that 50% of respondents indicated they use HOME less now than 5 years ago, and 24% plan to use it less over the next 2 to 3 years. Parental presence in the operatory appeared to be a common practice for some procedures and for children with special health care needs. The majority of respondents believed that parenting styles had changed in ways that adversely impacted children's behavior in the dental setting. CONCLUSIONS: Most practitioners have not changed their use of behavior management techniques in recent years, nor do they plan to change their use of them in the near future. HOME was the exception to these trends.

Survey of behavior management teaching in pediatric dentistry advanced education programs.

PURPOSE: The purpose of this study was to survey pediatric dentistry advanced education program directors regarding the teaching of behavior management techniques. METHODS: Surveys were mailed to all (65) advanced education programs in the United States. Follow-up mailings were sent to nonrespondents. The survey contained items on program demographics and the program's teaching of communicative and pharmacologic techniques. Information was also obtained on informed consent and parental presence in the operatory. RESULTS: Surveys were returned by 54 programs. Two programs declined to respond because they had not yet accepted or certified residents. The final response rate was 86%. The mean percentage (+/- SD) of total didactic time devoted to behavior management was 13% (+/-9.5). Communicative techniques were taught as "acceptable" by 98% of programs, with the exception of the hand-over-mouth exercise (HOME), which was taught as "unacceptable" by 54% of programs. Active and passive immobilization of sedated and nonsedated children was taught as "acceptable" by 76% to 98% of programs. All programs taught that pharmacologic techniques (nitrous oxide, conscious sedation, general anesthesia) are "acceptable." There was little evidence that the teaching of behavior management techniques had changed over the previous 5 years, nor that it is likely to change in the near future. Parental presence in the operatory was common for some procedures, particularly among younger children. CONCLUSIONS: Most programs do not teach HOME as an acceptable behavior management technique. The amount of curricular time devoted to behavior management is not likely to change appreciably in the near future.