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Aim. We investigated the long-term effects of exposure to concentrated growth factors (CGFs) on the regenerative properties of dental pulp stem cells (DPSCs) in the presence and absence of lipopolysaccharide (LPS) as a proinflammatory agent. Methods. DPSCs were cultured with CGF at different concentrations of LPS (0.1, 1, and 10 µg/ml) for 21 days. Then, using MTT and scratch assays, the cell viability and migration were examined. Osteogenic stimulation was evaluated by alkaline phosphatase (ALP) staining and Sirius Red staining, which determined the ALP activity and collagen levels, respectively. The expression levels of osteogenic markers were quantified using the qRT-PCR method. One-way analysis of variance (ANOVA) and Tukey’s HSD test were used to analyze differences between groups. Results. Long-term treatment of DPSCs with CGFs reduced LPS-induced cell death. Moreover, CGF and LPS (1 µg/ml), either in combination or alone, improved the DPSC migratory ability and caused a significant increase in osteogenic stimulation through the upregulation of collagen levels and ALP activity. Additionally, CGFs significantly upregulated RUNX2, DSPP, OCN, and OPN mRNA levels (as osteogenic markers), while LPS (1 µg/ml) only significantly increased OCN overexpression. Conclusion. Our findings are evidence that CGF could be a promising agent to induce dentin-pulp complex healing in long-term chronic inflammation.

Introduction: Dentin bond strength of the perforation repair materials is one of the effective factors on the materials sealing ability and success of the treatment. The aim of this study was to evaluate the effect of phosphate-buffered saline (PBS) on the push-out bond strength of White Mineral Trioxide Aggregate (WMTA) in the presence of blood contamination in simulated furcation perforations. Materials and Methods: This study was performed in Dental and Periodontal Disease Research Center in Tabriz Dental Faculty with the ethics code of IR.TBZMED.REC.B1396.819 in 2017. The furcation perforation measured with 1.3 mm diameter and 2 mm height was created in the 60 mandibular molars, and then the specimens were divided into four groups of 15 samples. In groups 1 and 3, only irrigation with normal saline after perforation establishment was done. In groups 2 and 4, blood contamination was created in the walls of perforation. Afterward, one Gel tamp was placed under the perforations in all the teeth, and WMTA was placed in the perforations. The moistened cotton with normal saline was placed on the MTA in groups 1 and 4, and moistened cotton with PBS was placed on the MTA in groups 2 and 3. Instron test was done after 1 week using universal testing machine. Due to the normal distribution of the samples, the two-way analysis of variance was used for statistical analysis. P-value less than 0.05 was considered statistically significant. Results: In the presence and absence of blood contamination, the mean bond strength of WMTA in saline proximity was significantly higher than PBS (PPConclusion: The presence of PBS does not have any positive effect on the increase of the bond strength of WMTA.

Background. The aim of this study was to investigate the effect of different mixing methods (ultrasonic, amalgamator, and conventional) on the bacterial microleakage of white Portland cement (WPC) and white MTA (Tooth-colored Formula, Dentsply, Tulsa Dental, Tulsa, OK). Methods. A hundred human single-rooted permanent teeth were decoronated to obtain 14 mm of root length in all the samples. The root canals were cleaned, shaped and obturated. Three millimeters of each root apex were cut off and randomly divided into 6 groups of 15 each (3 groups for WMTA and 3 groups for WPC, each with 3 different mixing methods) and 2 positive and negative control groups (each containing 5 samples). Brain-heart infusion agar (BHI) suspension containing the bacterial species Enterococcus faecalis (ATCC 29212) was used for leakage assessment. Statistical analysis was carried out using descriptive statistics and Kaplan Mayer survival analysis with censored data and log rank test using SPSS 18. Statistical significance was set at P0.05). Conclusion. Bacterial microleakage in the studied samples was not significantly different in terms of the type of the mixing method.

Objectives: To investigate association between Polypharmacy and socio-demographic factors (including age, sex, education, and smoking) between the elderly residents of Kahrizak Charity Foundation (KCF). Methods & Materials: In a descriptive analytic cross-sectional study, 237 (134 female) elderly residents of KCF, aged 60 and more, included trough randomized cluster sampling, were studied for the number of medications used and the association between polypharmacy (concurrent use of 5 or more medications) and socio-demographic factors, including age, sex, education, and smoking. Results: The mean number of medications used by any resident and the prevalence of polypharmacy were 5.1(±3.22) and 52.3% respectively. Compared with the 60-69 age group, the odds of polypharmacy, insignificantly increased in 70-79 age group (OR=1.09, 95%CI: 0.53-2.25) and decreased in 80 and more age group (OR=0.68, 95%CI: 1.24-0.37). The prevalence and odds of polypharmacy were insignificantly lower in men (OR=0.68, 95% CI 0.37-1.24) and significantly lower in smokers (OR=0.36, 95% CI 0.79-0.17). There was a significant direct association between polypharmacy and more formal education years (OR=1.09, 95%CI: 1.18-1.01). Conclusion: The mean number of medications for any resident and the prevalence of polypharmacy were high in KCF. Increase in years of official education and non-smoking were risk factors of polypharmacy in this population. There was no significant association between age and sex with polypharmacy. The future well-designed national studies among older people living in nursing homes are highly suggested.

Introduction: The aim of this in vitro study was to compare polymicrobial microleakage of calcium enriched mixture (CEM) cement, mineral trioxide aggregate (MTA), amalgam, and composite resin as intra-orifice sealing materials. Materials and Methods: Seventy single-rooted mandibular premolars were instrumented and obturated by cold lateral compaction technique. The teeth were randomly divided into four experimental groups according to used material: CEM, MTA, amalgam and composite resin (n=15) and two control groups (n=5). In experimental groups, 2 mm of coronal gutta-percha was removed and replaced with the study material. All the teeth were mounted in a two-chamber apparatus and the coronal portion was exposed to human saliva. The day the turbidity occurred was recorded for each sample. Data were analyzed using one-way ANOVA. Results: The negative control group showed no leakage while the average microleakage time in the positive control group was 3.5 days. The average bacterial leakage times for amalgam, composite resin, MTA, and CEM groups were 27.42±3.6, 29.35±3.15, 52.57±2.87, and 50.42±2.73 days, respectively. There was no significant difference between CEM and MTA groups (P=0.27) and also between amalgam and composite resin groups (P=0.36). However, in term of average leakage time, MTA and CEM groups exhibited significant differences with amalgam and composite resin groups (P

Background and aims. The knowledge of variations in root canal morphology is critical for a successful endodontic treatment. The purpose of this study was to investigate variations in the root canal system of human mandibular first permanent molars in an Iranian population. Materials and methods. In this study, 209 mandibular first molar teeth were decalcified, dye-injected, and cleared in order to determine the number and configuration of the root canals. Results. The results demonstrated that 65.56% of the mandibular first molars under study had three, 31.57% had four and 2.87% had two canals. Conclusion. According to the results of this study and considering variations in the root canal systems of the mandibular first molars, it seems that great care should be taken in the root canal treatment of these teeth.

Background and aims. It is critical to have a proper knowledge of the normal anatomy of the pulp and its variations for the success of endodontic treatment. The aim of this study was to determine the canal configuration and the prevalence of C-shaped canals in mandibular first and second premolars in a North-Western Iranian population. Materials and methods. A total of 163 extracted mandibular first and 103 mandibular second premolars were injected with India ink and demineralized . They were made clear and transparent with methyl salicylate and the anatomy of their canal(s) was studied. Results. The results showed that 98% of mandibular first premolars had one root, 2% had two roots, 70.6% had one canal, 27.8% had two canals, 1.2% had three canals and the prevalence of C-shaped canals was 2.4%. All mandibular second premolars had one root, 80.5% had one canal, 17.5% had two canals and the prevalence of C-shaped canals was 2%. Conclusion. It is important that clinicians, before treatment of mandibular first and second premolars, pay complete attention to radiographs, have a true concept of the number of root(s) and canal(s), and prepare a correct access cavitiy.

Background and aims. It is critical to have a proper knowledge of the normal anatomy of the pulp and its variations for the success of endodontic treatment. The purpose of this study was to investigate variations in the root canal system of maxillary first permanent molars in an Iranian population. Materials and methods. In this study, 137 maxillary first molars were decalcified, dye-injected, cleared and studied. Results. The results demonstrated that 37.96% of the maxillary first molars under study had three canals, 58.4% had four canals and 3.64% had five canals. Conclusion. According to the results of this study and considering variations in the root canal systems of maxillary first molars, it seems that great care should be taken in the root canal treatment of these teeth.