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Objectives: The aim of the present study is to evaluate the released residual monomers from composite resins that contain different proportions of bioactive glass (BAG). Methods: Experimental resin composites were prepared by a resin matrix (50% BisGMA and 50% TEGDMA) and inorganic filler with BAG (5, 10 and 30%). Each resin composite was placed in the tooth cavity (n = 5). After polymerisation, samples were immediately immersed in 75% ethanol and 25% deionised water (6 ml) at 37 °C. Residual monomers (Bis-GMA, TEGDMA, HEMA and UDMA) that were eluted from the composites for 10 m, 1 h, 1 d, 7 d and 30 d were analysed by high-performance liquid chromatography (HPLC). The data were analysed with one-way ANOVA and Tukey HSD at a p < 0.05 significance level. Results: Among the time periods, the fastest released residual monomer was observed in the 10 m elution. The highest amount of released residual monomer from all groups (except the control group) was TEGDMA, whereas this was HEMA for the control group. The amounts of residual monomers eluted from BAG30 were significantly higher than other groups (p < 0.05). Conclusions: The release of the monomer increases in accordance with the increased BAG addition to the composite resins. [ABSTRACT FROM AUTHOR]

Periostitis ossificans (PO) is a specific type of chronic osteomyelitis. Radiographically, it is characterized by the presence of lamellae of newly formed periosteal bone outside the cortex, giving the characteristic appearance of "onion skin." The most common cause of PO is periapical infection of the mandibular permanent first molar, which occurs primarily in children and young adults. Treatment in these cases is directed toward eliminating the source of the infection, either by extraction of the offending tooth or endodontic therapy. he purpose of this paper is to present a case of PO involving a permanent mandibular first molar managed with endodontic treatment. [ABSTRACT FROM AUTHOR]

Objective. The aim of this study was to evaluate the effect of different surface treatments on the microtensile bond strength (μTBS) and shear bond strength (SBS) of resin-modified glass ionomer cement (RMGIC) to dentin. Materials and methods. Fifty-two extracted human molars were flattened to obtain dentin surfaces. For SBS assessment 40 teeth were divided into four groups according to their surface treatments (acid etching, Er:YAG laser QSP mode, Er:YAG laser MSP mode and control-SiC) ( n = 10). A plastic cylinder was placed over the differently treated dentin surfaces and RMGIC was placed into the rings and polymerized. Twelve teeth were used for the μTBS test. The treated dentin surfaces described above were restored with 4 mm high RMGIC and light cured; then, the specimens were sectioned into serial sticks ( n = 15) and μTBS and SBS were tested for failure in a testing machine with a 1 mm/min crosshead speed. The data were analyzed by one-way ANOVA and Tukey HSD tests ( α = 0.05). Results. Acid etching showed significantly higher SBS than the other groups ( p < 0.05). Er:YAG QSP and MSP-treated groups showed higher SBS values than the control group, but the difference was not statistically significant ( p > 0.05). Er:YAG MSP showed the highest μTBS value followed by acid etching, whereas the control group exhibited the lowest value ( p < 0.05) and the differences between the control group and Er:YAG QSP were not significant ( p > 0.05). Conclusions. The application of Er:YAG MSP mode and acid etching to dentin can be used for improving the bond strength of RMGIC. [ABSTRACT FROM AUTHOR]

The purpose of this study was to compare the temperature rise under normal and caries-affected primary tooth dentin during photopolymerization of two adhesives and resin-containing restorative materials. Caries-affected and normal dentin disks were prepared from extracted primary molars with only mesial or distal approximal caries (4 mm in diameter, 1 mm in height). Temperature rise during photopolymerization of adhesive materials was measured with a J-type thermocouple wire that was connected to a data logger. Data were analyzed with two-way ANOVA and independent samples t-test. Temperature rise under caries-affected primary tooth dentin disks was higher than that of normal primary tooth dentin disks during polymerization of both adhesive systems and resin-containing dental materials (p<0.05). It was found that adhesive systems induced a higher temperature rise during polymerization as compared to the resin-containing restorative materials (p<0.05). In particular, temperature rise during polymerization of adhesive materials exceeded 5.5°C under caries-affected primary tooth dentin. [ABSTRACT FROM AUTHOR]

Objective: To test the null hypothesis that when the equivalent total light energy is irradiated to three orthodontic adhesive resins, there is no difference between the microhardness and water sorption values regardless of the curing light sources. Materials and Methods: Samples were divided into six groups according to the combination of three orthodontic adhesives (Kurasper F, Light-Bond, Transbond XT) and two light intensities (quartz tungsten halogen [QTH] and high intensity quartz tungsten halogen [HQTH]). One half of each of the 40 samples of three adhesive pastes was polymerized for 20 seconds by a QTH light source, and the other half was polymerized for 10 seconds by a HQTH light source. Water sorption was determined and Vickers hardness was established with three measurements per sample at the top, center, and bottom. Statistical analysis was performed using two-way analysis of variance (ANOVA) with multiple comparisons (Tukey-HSD). Results: Statistically significant differences were found among all adhesives for water sorption and hardness values cured with QTH and HQTH. The HQTH curing unit resulted in higher values than did the QTH. The highest water sorption values were observed for Kurasper F cured with HQTH and the lowest value was observed for Transbond XT cured with QTH. For microhardness Light-Bond cured with HQTH produced the highest values, and Transbond XT cured with QTH produced the lowest. Conclusions: When the equivalent total light energy is irradiated to three orthodontic adhesive resins, there are significant differences between the microhardness and water sorption values cured with the QTH and HQTH light source. The null hypothesis is rejected. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the effect of three storage solutions and two storage durations on microshear bond strength (μ SBS) of a resin composite. Sixty non-carious human permanent molars were stored in three storage solutions (0.1% thymol, 10% formalin, and distilled water). Each tooth was separated mesio-distally into two parts. Specimens of the first part were stored for 24 hours, while specimens of the second part were stored for two months in the solutions. After each storage period, the enamel surface was convered with a composite resin in combination with an etch-rinse adhesive system. Specimens were then serially sectioned into sticks of 1 mm2 bond area and subjected to μ SBS test. There were no statistically significant differences between the two storage periods for each solution (p>0.05). The thymol solution group showed lower μ SBS values than those of distilled water for both storage periods (p<0.05). As for the formalin group, its μ SBS values were not statistically different from those of distilled water and thymol groups at each storage period (p>0.05). In conclusion, the thymol solution caused the μ SBS of the resin composite to decrease when compared to both formalin and distilled water after 24 hours and two months. However, the μ SBS of the resin composite was not affected by storage duration. [ABSTRACT FROM AUTHOR]

The objectives of this study were to compare the polymerization shrinkage of three orthodontic adhesives. In addition we wanted to determine the effectiveness of the high-intensity quartz tungsten halogen (HQTH) in curing orthodontic adhesives on polymerization shrinkage with that of the quartz tungsten halogen (QTH). A total of 120 glass ring molds were prepared using a low-speed saw. The internal surface of the glass rings were roughened and etched. Adhesive pastes were placed into the glass molds, which were sandwiched between two glass slides. Samples were divided into six groups according to the combination of three orthodontic adhesives (Kurasper F, Light Bond, and Transbond XT) and two light intensities. One half of each 40 samples of three adhesive pastes was polymerized for 20 seconds by a QTH (Hilux 350), and the other half was polymerized for 10 seconds by a HQTH (Optilux 501). The volumetric polymerization shrinkage for each system was measured through the specific density method modified by Puckett and Smith. Statistical analysis was performed using two-way analysis of variance for intergroup comparisons. The HQTH-curing unit resulted in a more polymerization shrinkage than did the QTH for all investigated adhesives. However, no statistically significant differences were found. The highest shrinkage was observed for Light Bond cured with HQTH (1.59 ± 0.82%), and the lowest value was observed for Transbond XT cured with QTH (1.23 ± 0.60%). There are no significant differences in polymerization shrinkage of the three investigated orthodontic adhesives when polymerized with a QTH or a HQTH. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the bonding ability of five current self-etching adhesives to caries-affected dentin on the gingival wall. Seventy extracted human molars with approximal dentin caries were employed in this study. In order to obtain caries-affected dentin on the gingival wall, grinding was performed under running water. Following which, specimens mounted in acrylic blocks and composite resins of the bonding systems were bonded to dentin with plastic rings and then debonded by shear bond strength. With Clearfil SE Bond, bonding to caries affected dentin showed the highest bond strength. With Optibond Solo Plus Self-Etch, bonding to caries-affected dentin showed higher shear bond strength than AQ Bond, Tyrian SPE & One-Step Plus, and Prompt-L-Pop (p<005). Further, the bond strengths of Clearfil SE Band and Optibond Solo Plus Self-Etch to sound dentin were higher than those of Prompt-L-Pop, AQ Bond, and Tyrian SPE & One-Step Plus (p<0.05). In conclusion, besides micromechanical interlocking through hybrid layer formation, bond strength of self-etch adhesives to dentin may be increased from additional chemical interaction between the functional monomer and residual hydroxyapatite. The results of this study confirmed that differences in bond strength among self-etching adhesives to both caries-affected and sound dentin were due to chemical composition rather than acidity. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine whether the application of two antibacterial mouth rinses to etched and unetched enamel affects the shear bond strength (SBS) of an orthodontic composite resin. Eighty-five lower human incisors were divided into five groups, ie, group 1; control group, no mouth rinse was used; groups 2 and 3: mouth rinses were applied to the intact enamel surface before etching; groups 4 and 5: mouth rinses were applied to the etched enamel. A bonding agent and a composite resin were applied to the teeth surface. For shear bond testing, the specimens were mounted in a universal testing machine, and an apparatus attached to a compression load cell was applied to each specimen until failure occurred. The data were analyzed using analysis of variance and Tukey honestly significance tests. Fracture modes were analyzed by Mann-Whitney U-test. There was no statistically significant difference between the SBS values of group 1 (31.64 ± 3.62 MPa) and group 4—five experimental applications (P ≥ .05). However, the SBS value of group 3 (36.56 ± 5.95 MPa) was significantly larger than those of group 4 (30.00 ± 4.97 MPa) and group 5 (30.26 ± 7.30 MPa). In addition, no significant differences were observed between group 1 and groups 2 (34.33 ± 7.26 MPa) and 3 (36.56 ± 5.95 MPa) (P ≥ .05). Because the application of chlorhexidine and povidone-iodine before acid etching did not cause any decrease in bond strength, it is advisable for use under the orthodontic resin composite to obtain an antibacterial effect or to prevent the risk of bacteremia. [ABSTRACT FROM AUTHOR]

Objective: The aim was to determine the antimicrobial effect of ozonated water, ozonated water with ultrasonication, sodium hypochloride and chlorhexidine (CHX) in human primary root canals contaminated by Enterococcus faecalis (E. faecalis)., Materials and Methods: Fifty-eight extracted human primary molar teeth were used. Crowns were cut off using a diamond saw under water-cooling. One hundred roots were obtained and mechanically prepared. The roots were then sterilized by autoclaving in water for 15 min at 121°C. All samples were contaminated with E. faecalis for 24 h and the root canals were randomly divided into five groups (n = 20). Group I: 25 mg/L of Ozonated water (O3aq), Group II: 25 mg/L of O3aq with ultrasonication, Group III: 2.5% Sodium hypochloride (NaOCl), Group IV: 2% CHX and Group V: Positive control. The canal of each specimen was irrigated for 4 min and positive control was untreated. All root canals were agitated with sterile saline solution. The saline solution was collected from canals with sterile paper points. For each specimen, the paper points were transposed to eppendorf vials containing 2 ml of brain heart infusion. According to bacterial proliferation, the mean values of optical density were achieved by ELİSA (Biotek EL ×800, Absorbance Microplate Reader, ABD) and the data were analyzed., Results: NaOCI, CHX and two types of O3aq were found statistically different than positive control group. NaOCI irrigation was found significantly most effective., Conclusions: NaOCl, CHX and O3aq applications provide antibacterial effect in vitro conditions in primary root canals.

Objectives: The aim of this study was to test the hypothesis that the bonding ability of antibacterial bonding system to primary dentin was not different from the parental material which did not contain any antibacterial component., Methods: Extracted human non-carious primary molars were ground to expose the coronal dentin, and then randomly divided into two experimental groups: treatment with Clearfil Protect Bond or with Clearfil SE Bond (Kuraray Medical Inc.). Composite-dentin sticks with a cross-sectional area of approximately 0.90 mm(2) were prepared and subsequently subjected to microtensile bond strength (muTBS) and microshear bond strength (muSBS) tests. For the muTBS tests, specimens were attached to an Instron testing machine with a cyanoacrylate adhesive. For muSBS testing, the sticks were mechanically fixed to the muSBS testing apparatus. The bonds were stressed in shear or tension at a crosshead speed of 1mm/min until failure occurred. Resin-dentin interfaces produced by each system were examined using SEM. The data were analyzed with Mann-Whitney's U test., Results: The muTBS and muSBS of Clearfil Protect Bond were 30.69+/-9.71 and 9.94+/-3.78 MPa, respectively. Clearfil SE Bond showed significantly greater values of 37.31+/-9.57 and 12.83+/-3.15 MPa, respectively. SEM analysis demonstrated similar micro-morphological features including the thickness of the hybrid layer for both materials., Conclusions: It was showed that antibacterial self-etching system Clearfil Protect Bond showed lower bond strength values compared to primary dentin than that of to Clearfil SE Bond on primary dentin. (Eur J Dent 2008;2:11-17).

Objectives: The aim of this study was to determine the fluoride levels in breast milk and plasma of lactating mothers who regularly consumed drinking water with low levels of fluoride., Methods: One hundred twenty five healthy mothers aged between 20-30 years old who had given birth within 5-7 days were included in the study. Besides being otherwise healthy, the primary selection criteria stipulated the absence of fluoride supplement consumption one month before delivery. Approximately 5 ml breast milk and 5 ml blood samples were obtained from each participating mother at a hospital setting, where the mothers were scheduled for a regular hospital diet. The blood samples were centrifuged in fluoride-free heparinized polyethylene tubes and stored at -18 degrees C until measurements were made. Breast milk samples were directly refrigerated as with blood samples until measurements. The fluoride concentrations of milk and blood samples were assessed using an ion-selective fluoride electrode combined with an ion analyzer., Results: The fluoride levels of the plasma and breast milk samples were measured as 0.017+/-0.011 ppm and 0.006+/-0.002 ppm, respectively. The fluoride concentration of plasma was significantly higher than that of breast milk (P<.01). Correlation analysis revealed a significant relation between the groups (P<.01)., Conclusion: A limited level of fluoride transmission from plasma to breast milk was detected. Nevertheless, a significant correlation between the fluoride concentrations of breast milk and plasma was evident.

A self-etching dentin adhesive was evaluated for its ability to bond to caries-affected and sound dentin after applying three desensitizers to the gingival walls. Sixty extracted human molars, with approximal dentin caries, were cut horizontally on the long axis of the tooth through caries-affected gingival walls. Carious dentin was removed with SiC paper by means of a caries detector to expose caries-affected dentin. The molars were randomly assigned to four groups: control and three experimental groups-Micro Prime, Glauma Desentizer and Cervitec. Desensitizers were applied to the dentinal surfaces according to manufacturers' instructions. A resin composite was bonded to both the caries-affected and sound dentin of each tooth using a bonding system and plastic rings. The restoration was debonded by shear bond strength. The application of Micro Prime and Gluma Desensitizer to caries-affected dentin did not show any effect on bond strength testing. However, Cervitec caused a decrease in bond strength to caries-affected dentin. The effect of desensitizers on the bond strength of the self-etch bonding agent to caries-affected dentin changed according to the chemical composition of the materials. Desensitizer application on sound dentin is recommended with self-etch bonding systems.

The purpose of this study was to determine whether the application of two antibacterial mouth rinses to etched and unetched enamel affects the shear bond strength (SBS) of an orthodontic composite resin. Eighty-five lower human incisors were divided into five groups, ie, group 1: control group, no mouth rinse was used; groups 2 and 3: mouth rinses were applied to the intact enamel surface before etching; groups 4 and 5: mouth rinses were applied to the etched enamel. A bonding agent and a composite resin were applied to the teeth surface. For shear bond testing, the specimens were mounted in a universal testing machine, and an apparatus attached to a compression load cell was applied to each specimen until failure occurred. The data were analyzed using analysis of variance and Tukey honestly significance tests. Fracture modes were analyzed by Mann-Whitney U-test. There was no statistically significant difference between the SBS values of group 1 (31.64 +/- 3.62 MPa) and group 4-five experimental applications (P > or = .05). However, the SBS value of group 3 (36.56 +/- 5.95 MPa) was significantly larger than those of group 4 (30.00 +/- 4.97 MPa) and group 5 (30.26 +/- 7.30 MPa). In addition, no significant differences were observed between group 1 and groups 2 (34.33 +/- 7.26 MPa) and 3 (36.56 +/- 5.95 MPa) (P > or = .05). Because the application of chlorhexidine and povidone-iodine before acid etching did not cause any decrease in bond strength, it is advisable for use under the orthodontic resin composite to obtain an antibacterial effect or to prevent the risk of bacteremia.