Objective Assess Biodentine as an indirect pulp capping material for treatment of young first permanent molars with deep carious lesions and its microleakage (in vitro). Materials and methods Indirect pulp capping was performed on 60 young permanent molars in 30 children aged 6–10 years then were randomly divided into two treatment groups of 30 molars for each group. Group I: The pulp was indirectly capped with Biodentine. Group II: The pulp was indirectly capped with Dycal. At the same appointment, the tooth was restored with Medifil as a semipermanent restoration. Clinical evaluation and standardized periapical radiographs were done after 3, 6 and 9 months. Microleakage test was assessed by dye penetration technique and followed up after 24 h, 1 and 3 months. Results The two groups were clinically successful as Biodentine showed 100% success rate and Dycal showed 92.6%. There was no statistically significant difference (P > 0.05) between the two groups regarding to their clinical performance. While the radiographic examinations showed that Dycal had lower radiographic success rate (85.2%) in comparison to Biodentine (100%). Biodentine showed superior sealing ability than Dycal, with no statistically significant difference in the microleakage between the two tested materials (P > 0.05). Conclusion Biodentine is a promising material as an indirect pulp capping agent and exhibits superior sealing ability than Dycal.

Purpose Of this study was to compare the antimicrobial efficacy of green tea (0.5%) mouth rinse to that of chlorhexidine (CHX) (0.125%) against Streptococcus mutans and Lactobacilli spp. Participants and methods Forty-two children had early childhood cairns were recruited in this study, and randomly divided, using lottery method, into three groups; group A: children using green tea mouthwash; group B: children using CHX (0.12%) mouthwash; group C: children using colored flavored nonsweetened tape water. They were instructed to rinse the mouth for 1 min using 5 ml of the respective mouth rinse 30 min after the tooth brushing for 2 weeks. A volume of 2 ml saliva samples were collected prior to the commencement of mouth rinsing, and after 2 weeks rinsing, data were collected and statistically analyzed. Results Revealed both CHX and green tea mouth rinses showed a statistically significant fall in the colony counts of S. mutans and Lactobacilli spp. (P < 0.001 and <0.001), while in the third group not statistically significant (P = 0.003 and 0.183) for S. mutans and Lactobacilli spp., respectively). When the antimicrobial efficacy of CHX and green tea was evaluated against both S. mutans and Lactobacillus spp., no statistically significant difference was found (P = 0.462 and 0.824, respectively).

Objective The objective of this study was to synthesize and characterize inorganic zirconium oxide (ZrO₂), organic [bisphenol A diglycidyl ether dimethacrylate (Bis-GMA)+triethylene glycol dimethacrylate (TEGDMA)+polyethylene glycol dimethacrylate (PEGDMA)] and hybrid (ZrO₂+ Bis-GMA + TEGDMA) nanofibers and the use of these nanofibers for improving flexural strength (FS) and flexural modulus (FM), fracture toughness (FT) and impact strength (IS) of polymethyl methacrylate (PMMA) resin. Materials and methods Inorganic, organic and hybrid nanofibers were synthesized by wet electrospinning technique. The study was divided into four groups according to the type of added nanofibers (6%) to the heat-curing PMMA denture base resin; control group: PMMA without nanofibers, inorganic group: PMMA with silanized ZrO₂ nanofibers, organic group: PMMA with Bis-GMA/TEGDMA/PEGDMA nanofibers and hybrid group: PMMA with ZrO₂/Bis-GMA/TEGDMA nanofibers. According to ISO FDIS 20795-1:2013, three-point bending test was used to measure FS, FM and FT for each group (n = 10). According to ISO 197-A1: 2005, impact tester was used to measure IS for each group (n = 10). One-way analysis of variance was used for statistical significance between groups and post-hoc (Tukey's test) was used for multiple comparisons. P value less than or equal to 0.01 was considered significantly different. Results The synthesized pure forms of three types of nanofibers were characterized by scanning electron microscope and Fourier transform infrared spectroscopy. Nanofibers-reinforced groups (ZrO₂, hybrid and organic, respectively) recorded high means % than that of the control group as follows: 205, 184 and 170% for FS (MPa), 184, 149 and 120% for FM (GPa), 210, 189 and 177% for FT (MPa m^1/2) and 151, 180 and 176% for IS (KJ/m²). In each of the four tested mechanical properties, one-way analysis of variance revealed a significant differences between the studied groups (P = 0.000) and post-hoc (Tukey's test) revealed that nanofibers-reinforced groups were markedly significantly higher than control group (P = 0.000). Conclusion ZrO₂, Bis-GMA/TEGDMA/PTEGDMA and ZrO₂/Bis-GM/TEGDMA hybrid nanofibers synthesized by electrospinning technique improved significantly FS, FM, FT and IS of PMMA resin (P = 000).

Aim To evaluate the apical seal for two different adhesive sealers used with two different rotary systems. Materials and methods Forty extracted single-canaled premolars were cleaned, decoronated into equal length root specimens and randomly divided into two equal groups (n = 20). Root canals of root specimens in group 1 were prepared using iRace rotary files while those of group 2 were prepared using ProTaper Next files. Specimens of each group were further subdivided into two equal subgroups (n = 10). Specimens in subgroup 1 were obturated using bioceramic sealer while those of subgroup 2 were obturated using resin sealer. Microleakage test was conducted using dye penetration and longitudinal sectioning technique. Collected data were statistically analyzed using one-way analysis of variance and Tukey's comparison to stand over the difference between the tested subgroups at significance level of P value less than 0.5. Results There were no statistically significant difference between the tested subgroups and the sealers showed a comparable and satisfactory sealability. Conclusion Both bioceramic and resin sealers are comparable in their sealing ability when used for obturating root canals that were prepared with either iRace or ProTaper Next rotary files.

Introduction This study investigated the influence of nano-silver fluoride (NSF), nano-hydroxyapatite (N-HAP), and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) paste treatments on the enamel surface microhardness (SMH) after dental bleaching in vitro. Materials and methods A total of 60 samples were randomly divided into four groups (n = 15) according to the surface treatment material as the following: (a) control (no treatment), (b) NSF, (c) N-HAP, and (d) CPP-ACP paste. Baseline SMH test of the samples in each group was tested by Vickers microhardness tester. The samples were bleached with 40% hydrogen peroxide for three times (20 min each time). Then NSF, N-HAP, and CPP-ACP paste were applied for 10 days and 2 min/day. The SMH was measured after 24 h and the data were statistically analyzed by one-way analysis of variance. Results Postbleaching SMH values decreased in all groups (P ≤ 0.00.1). Post-treatment SMH values significantly increased in comparison to postbleaching values (P ≤ 0.001) except for control group which was not different statistically (P = 0.68). The highest SMH values were observed in NSF group (mean: 238.84 ± 20.31). Statistically significant differences were shown between all groups (P ≤ 0.05). Conclusion The use of the remineralizing materials is important in clinical practice to reduce the undesirable changes of enamel surface after bleaching procedures.

Aim This study compared the amount of debris extrusion of different irrigation activation techniques. Materials and methods Sixty single rooted maxillary incisor human teeth with single and straight canals were used. The crowns were flattened to obtain a standardized working length. The specimens were placed into Eppendorf tubes to collect the debris. The root canals were instrumented using the ProTaper Next system. The specimens were randomly divided into four equal groups in terms of the irrigation activation techniques; group I, no activation; group II, manual dynamic agitation; group III, passive ultrasonic irrigation; and group IV, Xp-endo Finisher. A total of 10 ml of distilled water was used during the irrigation procedures of each specimen. The tubes were stored in incubator for 5 days. The amount of debris extrusion was calculated by subtracting the initial weight from the final weight of the tube. The distribution of the data was examined using the Shapiro–Wilk test. Mann–Whitney U- test was used for post-hoc group comparisons. Results Debris extrusion was recorded for all specimens. The no activation group demonstrated significantly less amount of debris extrusion compared to all activation groups (P < 0.05). No differences were found between other groups (P > 0.05). The mean values for manual dynamic agitation, passive ultrasonic irrigation, and Xp-endo Finisher groups were found as 0.00114733 g, 0.00091733 g, and 0.00100 g, respectively. Conclusion Although activation techniques caused a higher amount of debris extrusion, their benefits and limitation of in-vitro conditions to reflect clinical situations should be well considered.

Objective Insulin-like growth factor binding protein-3 (IGFBP-3) has been linked to the pathology of multiple inflammatory diseases of immunological background. Till now, no data is available on the involvement of IGFBP-3 in oral lichen planus (OLP) pathogenesis. Thus we aimed to gather preliminary data concerning salivary levels of IGFBP-3 and its binding protein transferrin (Tf) in patients suffering from OLP compared to normal controls and correlate it with clinical picture, this is to investigate: (a) a possible role in pathogenesis and (b) its validity as a biomarker for disease activity. Patients and methods Salivary samples from 40 patients suffering from OLP (clinically evaluated using REU scoring system) and 40 controls were collected and Tf and IGFBP-3 levels were estimated using enzyme-linked immunosorbent assay, for statistical analysis, analysis of variance followed by Turkey's post hoc and Pearson's correlation tests were used. Results Significantly higher salivary levels of IGFBP-3 and Tf (2533.45 ± 290.35 and 13.91 ± 2.23 ng/ml, respectively) were recorded in OLP compared to controls (1215.3 ± 428.92 and 3.33 ± 0.24 ng/ml, respectively, P < 0.0001). A positive correlation between IGFBP-3 and Tf levels with REU in OLP was detected. Conclusion Our data suggests that IGFBP-3 and Tf seem to play a role in pathogenesis of OLP and could be considered as a reliable marker in monitoring disease activity. However, further studies are required to further elucidate the role of the TGFBP-3/Tf binding system in the pathogenesis of OLP.

Objective The aim of this study was to assess impact of cyclic loading on screws attached to four different abutments to internally connected implants. Materials and methods Four groups (seven implants each) of dissimilar abutments were included in this study. Abutments were connected to Straumann tissue-level implants. Each implant was rigidly secured in a stainless steel cylindrical jig. A torque controller was used to tighten the abutments at 35 N cm. A 150 N cyclic load for 1 million cycles was applied to the implant at a 30° angle to the long axis to the implants. Periotest values (PTVs) were measured before and after cyclic loading and a digital torque gauge used to detect the removal torque values (RTVs) of abutments. The data were analyzed statistically using SPSS and Kruskal–Wallis tests and one-way analysis of variance were used to compare RTVs and PTVs after application of equal loads for each group. The Spearman correlation coefficient was applied to compare RTVs and PTVs after loading. Results The Straumann solid abutment and the Southern solid abutment showed no mechanical failures. Screws fracture was noted in nearly 85% of Implant Direct abutment, and 55% of the Blue Sky Bio abutments. The final mean PTV of the Blue Sky Bio abutments, the Southern Implants, and Implant Direct straight abutment was considerably higher than the final mean PTVs of Straumann solid abutment. Conclusion Abutments from the different manufacturers have different physical and chemical characteristics. So there was a potential risk of mechanical failure when the interchangeable abutments are used. Thus, the use of an abutment manufactured by the same implant company is highly recommended for the avoidance of loosening of the abutment screws.

Aim To evaluate the effect of irrigation solutions [sodium hypochlorite (NaOCl), chlorhexidine (CHX), and normal physiological saline] and different irrigation techniques (conventional needle, EndoVac, and CanalBrush) on push-out bond strength of AH Plus resin-based sealer. Materials and methods Ninety mandibular freshly extracted premolars were selected and divided into three groups according to the irrigation solutions; group I: 5.25% NaOCl, group II: 2% CHX, group III: normal physiological saline solution. Then each group was subdivided into three subgroups according to the irrigation techniques; subgroup A: 27 G side beveled needle, subgroup B: EndoVac irrigating system, subgroup C: medium-sized CanalBrush (30/0.04). Root canals of all groups were prepared using ProTaper Universal Ni-Ti rotary system up to file F4 (40/0.06) and filled by single cone technique using AH Plus sealer. 2 mm thick horizontal sections from the coronal, middle and apical thirds of each root were sliced for the push-out bond strength measurement and tested using universal testing machine. Data were analyzed using one-way analysis of variance in a level of significance (P ≤ 0.05). Results The highest mean push-out bond strength values were recorded for EndoVac system followed by CanalBrush and Needle in all groups and at all root canal levels. In comparison of irrigation solutions in needle subgroup; the highest values were recorded for CHX and least for NaOCl at coronal and middle root levels. While in the apical section, the highest and least mean push-out bond strength values were recorded for CHX and saline respectively. Regarding EndoVac and CanalBrush; the highest push-out bond strength values were recorded for CHX followed by saline and NaOCl at all root canal levels. Conclusions Whenever root canal obturation using AH Plus sealer, it is preferred to use 2% CHX solution throughout and after instrumentation via EndoVac system for improved bond strength. The coronal sections showed higher bond strength than middle and apical sections.