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Objective: The present study evaluated the pulp tissue response following direct pulp capping (DPC) with several materials in dogs' teeth. Methods: This study was performed on four doges with 64 mature healthy premolars and molars. The teeth randomly received the following materials: platelet-rich plasma (PRP), propolis, MTA, and glass-ionomer cement (GIC, negative control group). Afterwards, the teeth were restored with light cure GIC. Half of the animals were sacrificed after seven and half after 30 days. Histologic samples were prepared (n=8 per material/interval), and the levels of inflammation, and fibrous and calcified tissue formation were compared between the groups and intervals. Results: After seven days, inflammation and calcified tissue levels were comparable among the groups (P> 0.05). The MTA group showed significantly more fibrous tissue formation than the GIC samples (P<0.05). After 30 days, propolis and MTA showed significantly lower inflammation than GIC (P<0.05). PRP and MTA groups showed significantly higher fibrous tissue formation than the GIC group (P<0.05). Moreover, GIC showed the lowest calcification level among the groups, and PRP had lower calcification than MTA (P<0.05). Inflammation levels of the experimental groups decreased after 30 days, but the change was not significant (P>0.05). Fibrous tissue formation in the MTA and propolis groups decreased significantly after 30 days (P<0.05). Calcification levels of the experimental groups increased significantly over time (P<0.05). Conclusions: The findings suggest that propolis might be a favorable substitute for MTA in DPC procedures, as it produced comparable results to MTA in reducing inflammation and enhancing calcification. [ABSTRACT FROM AUTHOR]

Background: Electrochemical disinfection of the root canal system (RCS) is introduced as an alternative to conventional irrigation. The aim of this study was to assess the efficacy of depotphoresis method in the disinfection of accessible and inaccessible RCSs. Materials and Methods: In this comparative in vitro study disinfection of Enterococcus faecalis infected RCS using two methods, (1) depotphoresis and (2) sodium hypochlorite (NaOCl) irrigation plus passive ultrasonic agitation (PUA) took place on 40 extracted maxillary anterior teeth. Decoronation was done with a diamond disc, and the canals were instrumented. The roots were divided into two phases: the specimens with canal obstruction and the specimens without canal obstruction. The smear layer was removed, and the specimens were infected for 21 days with E. faecalis. After disinfection procedures, bacterial samples were taken using two sterile #35 paper points, and colony forming units (CFU) were counted. Data were analyzed statistically using the Kruskal--Wallis test, with a significance level at P < 0.05, to indicate differences between depotphoresis and NaOCl plus PUA groups. Results: In both phases, Log CFU after depotphoresis treatment was significantly lower than NaOCl irrigation plus PUA treatment (P < 0.05). Conclusion: Treatment with depotphoresis was significantly more effective than NaOCl irrigation plus PUA treatment. [ABSTRACT FROM AUTHOR]

Background: Mineral trioxide aggregate (MTA) becomes a hard mass after setting and making it difficult to remove and can cause significant problems in the retreatment process. The aim of this study was to evaluate the effect of different concentrations of hydrochloric acid (HCl) on MTA dissolution and its effect on dentin. Materials and Methods: In this in vitro study, 45 single-root premolars were selected. Artificially open apex was created in all samples with similar process. The samples were randomly divided into 4 experimental groups of 10, and a control group of 5. Four-millimeter thick apical plugs of Root MTA were placed in all samples in an orthograde manner. HCl was used at concentrations of 3.75%, 7.5%, 15%, and 22.5% (w/v) for the experimental groups and normal saline for the control group. Each sample was exposed to the desired solution for 15 min. Then, MTA retrieval and reaching the working length were attempted with k-file # 30. The times of each sample were recorded. Furthermore, after longitudinal incision of the roots with a disc, the dentin surfaces of canals were examined with a Dino-Lite microscope (x50). Results were analyzed by Shapiro-Wilk test and one-way analysis of variance tests. The level of significance P value was set at 0.05. Results: The lowest average time of reaching working length was observed with group 22.5% that was significantly lower than 15% and 7.5% concentrations (P = 0.005 and P = 0.011). Furthermore, by examining with x50 of Dino-Lite microscope, no difference was observed on the canal walls. Conclusion: The optimum concentration of HCl was 7.5%. Furthermore, different concentrations of HCl had no significantly different effect on the dentinal canal wall using Dino-Lite microscope with x50. [ABSTRACT FROM AUTHOR]

Statement of the Problem: One of the rare adverse effects in patients who take bisphosphonates is the osteonecrosis of the jaw in the oral cavity following any trauma such as tooth extraction. Purpose: The aim of this study is the histopathological evaluation of the jaw following intra-ligament anesthesia injection in Zoledronate-treated rats. Materials and Method: In this descriptive-experimental study, rats weighing 200-250 g were divided into 2 groups. The first group received a 0.6 mg/kg dose of zoledronate and the second group received normal saline. Five injections with a 28-day interval were performed. At the end of the injection, the animals were sacrificed. Then, five-micrometer histological slides were prepared from the first maxillary molars and the surrounding tissues. Hematoxylin and eosin staining was performed to evaluate osteonecrosis, infiltration of inflammatory cells, fibrosis, and root and bone resorption. Results: There was no difference between the macroscopic and clinical features in both groups and no evidence of osteonecrosis of the jaw was observed in the samples. From the histological point of view, all the samples had normal tissues and none of them showed any evidence of inflammation, tissue fibrosis, disorder, or pathological root resorption. Conclusion: According to the histological findings, the periodontal ligament space, the bone adjacent to the roots, and the dental pulp conditions were similar in both groups. Osteonecrosis of the jaw did not develop in the rats that took bisphosphonates after intraligamental injection. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the outcome of apexogenesis with mineral trioxide aggregate (MTA) in traumatised anterior and carious posterior teeth over 5 years. A comprehensive chart review was performed to obtain a retrospective of sequential previously completed cases with recalls. Clinical and radiographic data were collected for 97 vital immature teeth (40 traumatised anterior and 57 carious posterior teeth) pulpotomised (partial or full pulpotomy) using MTA with an average follow‐up time of 5 years. Chi‐squared test and Fisher's exact test were implemented to analyse data. The success rate in anterior teeth and posterior teeth was 82.5% and 96.4% respectively. Crown discolouration was observed in 25 (62.5%) anterior teeth. There was a significant difference between the number of successful and unsuccessful cases (P < 0.05) and there was no correlation between type of treatment and success/failure (P > 0.05). The success rate of apexogenesis using MTA in immature teeth was relatively high. [ABSTRACT FROM AUTHOR]

The housing sector is an important part of every community. It directly affects people, constitutes a major share of the building market, and shapes the community. Meanwhile, the increase of developments in hazard-prone areas along with the intensification of extreme events has amplified the potential for disaster induced losses. Consequently, housing recovery is of vital importance to the overall restoration of a community. In this relation, recovery models can help with devising data-driven policies that can better identify pre-disaster mitigation needs and post-disaster recovery priorities by predicting the possible outcomes of different plans. Although several recovery models have been proposed, there are still gaps in the understanding of how decisions made by individuals and different entities interact to output the recovery. Additionally, integrating spatial aspects of recovery is a missing key in many models. The current research proposes a spatial model for simulation and prediction of homeowners' recovery decisions through incorporating recovery drivers that could capture interactions of individual, communal, and organizational decisions. RecovUS is a spatial agent-based model for which all the input data can be obtained from publicly available data sources. The model is presented using the data on the recovery of Staten Island, New York after Hurricane Sandy in 2012. The results confirm that the combination of internal, interactive, and external drivers of recovery affect households' decisions and shape the progress of recovery. [ABSTRACT FROM AUTHOR]

Although postdisaster housing recovery is an important player in community recovery, its modeling is still in its infancy. This research aims to provide a spatial regression model for predicting households' recovery decisions based on publicly available data. For this purpose, a hierarchical Bayesian geostatistical model with random spatial effects was developed. To calibrate the model, households' data that were collected from Staten Island, New York, in the aftermath of Hurricane Sandy were used. The model revealed that on the scale of census tract, residents with higher income or larger household size were significantly less likely to reconstruct. In contrast, odds of reconstruction rose with increase of long‐term residents. The model outputs were also employed to develop a reconstruction propensity score for each census tract. The score predicts probability of reconstruction/repair in each tract versus others. The model was validated through comparison of the propensity scores with the distribution of Community Development Block Grant Disaster Recovery assistance and its resultant reconstruction. The validation indicated capability of the model to predict the potential hotspots of reconstruction. Accordingly, the propensity score can serve as a decision‐support tool to tailor recovery policies. [ABSTRACT FROM AUTHOR]