جستجوی مقالات مرتبط با کلیدواژه "fluid filtration" در نشریات گروه "پزشکی"

Apical surgery aims to eradicate the apical part of the root and the lesion to enhance the healing. The sealing ability of retrograde filling material is an essential factor affecting the success rate of the surgery. Mineral trioxide aggregate (MTA) is thegold standard of retrograde filling materials, with approved sealing capability and biocompatibility. Newly introduced root repair material with an approved antibacterial effect similar to MTA is Nano-fast cement (NFC) which should be investigated for its sealing ability. This study aimed to evaluate the sealing ability of NFC vs. MTA.

Root apices of 48 single-rooted teeth were resected at 90 degrees and were prepared at 3 mm depth. The teeth were randomly divided into 2 experimental groups (n=21), negative control group (n=3), and positive control group (n= 3). MTA and NFC plugs were condensed as retrograde filling material. The samples were evaluated by a modified fluid filtration device for 1 hour. The measurement was conducted at 24 h, 1, and 3 months. Data were analyzed by Friedman Test and Kruskal-Wallis test.

According to the results, NFC at 3-months interval showedthe least microleakage, and MTA had the highest at the baseline. However, the results between the two groups were not statistically significant in all intervals. NFC reached the ideal sealing ability within 1 month, which was reached for MTA after 3 months.

The results of this in vitrostudy showed that the microleakage value of NFC is comparable to MTA.In light of current findings, NFC shows characteristics of a suitable calcium silicate-based cement. Further clinical researches are needed to introduce the NFC as retrograde apical plug or for other endodontic applications.

The quality of root canal treatment depends on the sealing ability of root canal obturation materials. Sealers help create an impenetrable seal. This study aimed to compare the sealing ability of AH Plus and Sure-Seal Root sealers by the fluid filtration technique. This in-vitro study evaluated 80 extracted human mandibular second premolars. After initial preparation, the teeth were randomly divided into two experimental groups (n=35) and positive and negative control groups (n=5). The experimental groups were obturated with AH Plus sealer and Sure-Seal Root sealer. The AH Plus and the Sure-Seal Root groups were obturated with the lateral condensation technique and the single-cone technique, respectively. Apical leakage was assessed at two intervals of 1 week and 3 months, evaluated by the fluid filtration technique, and compared between the two groups using Student’s t-test. No significant differences were observed between the two groups in 7 days. However, after 90 days, the AH Plus group exhibited significantly less leakage than the Sure-Seal Root group. The microleakage of AH Plus decreased over time (P<0.05). In this study, AH Plus exhibited significantly better sealing ability than Sure-Seal Root in the long term.

AH26, Master-Dent, and Endoseal mineral trioxide aggregate (MTA) are three different types of sealers. The purpose of this study was to assess and compare THE apical seal of the root canal-treated teeth with the above-mentioned sealers in the presence and absence of moisture using the fluid filtration method.

To this end, 54 freshly extracted single root canal human canines were selected for this study. The canals were prepared using rotary instruments, and then sodium hypochlorite was applied as an irrigation solution in this protocol. The specimens were randomly divided into three groups of 18. One group was obturated with the gutta-percha by the cold lateral compaction technique. Half of one of the aforementioned sealers belonged to the group of moistened teeth and the other half to the group of the dried teeth. Microleakage in all groups was assessed 3 months after the obturation of canals by the fluid filtration method. The data were analyzed using ANOVA and Tukey’s post hoc tests, and the level of significance was set at P<0.05.

The results showed that the minimum and maximum micro-leakage belonged to Masterdent dry (mean leakage = 1.7778 μL/ min/CmH20) and Endoseal-MTA dry (mean leakage = 3.5000 μL/min/CmH20), respectively. All three groups of sealers exhibited a significant difference in apical micro-leakage between dry and moist conditions (PMasterdent <0.001, PAH26=0.002, and PEndoseaL-MTA =0.007).

The findings of this experimental study demonstrated that Masterdent provided the least apical micro-leakage under dry conditions while Endoseal-MTA had the highest micro-leakage under these conditions. There was a significant difference between dry and moist conditions in all groups.

 The present study aimed to evaluate the sealing ability of three different calcium silicate-based materials in furcation perforations.

 Seventy-six human mandibular molar teeth were selected. Perforations were created in the center of the pulp chamber floor. The experimental teeth were randomly divided into three groups (n=22). Perforations were repaired with MTA Angelus, Endocem MTA, or EndoSequence BioCeramic Root Repair Material Fast Set Putty (BC-RRM Putty). Microleakage of the different repair materials to be tested was measured by computerized fluid filtration method at 24- and 72-hour intervals.

 For each time interval, no statistically significant difference was observed between the groups. For Endocem MTA and BC-RRM Putty groups, the difference between the leakage values measured at both periods was not statistically significant (P>0.05). However, there was a significant difference for the MTA Angelus group (P<0.05).

 All the calcium silicate-based materials used in the present study showed similar performance in repairing furcation perforations at 24- and 72-hour intervals.

  Endodontic treatment failure is caused by the leakage of microorganisms and endotoxins, which leads to pathological lesions. Adequate seal of the root canal is essential to preventing recontamination and ensuring the long-term clinical success rate. Mineral trioxide aggregate (MTA) and calcium-enriched mixture cement (CEM) are common types of cement with adequate sealing capability in endodontics. The present study aimed to compare the microleakage in the root canals filled with ProRoot MTA and CEM cement using fluid filtration. This experimental, in-vitro study was conducted on 46 root canals of extracted mandibular premolars. After preparation and disinfection with 3% sodium hypochlorite, the crowns were resected from the cervical region. The teeth were randomly divided into two experimental groups of 20 based on the tested materials (ProRoot MTA and CEM cement), as well as two negative and positive control groups of three. All the samples were instrumented and obturated using the step-back technique, and fluid filtration was used to evaluate sealing ability and leakage inhibition. Data analysis was performed using the Mann-Whitney U test (α=0.05). Mean microleakage in the ProRoot MTA and CEM cement was 2±0.79 and 3.02±1.38 µL/8 min, respectively. In addition, a significant difference was observed between the two groups in this regard (P<0.011). According to the results, ProRoot MTA provided significantly less microleakage compared to the CEM cement. Therefore, the sealing ability of ProRoot MTA was higher than the CEM cement, which makes MTA a better material than CEM cement for canal obturation.

Statement of the Problem: Alkaline pH can affect the physical and chemical properties and sealing ability of apical plug material. Calcium hydroxide is used in non-vital teeth as an intracanal medication to complete disinfection of root canals. It raises the pH of environment to alkaline value.
The aim of this in vitro study was to evaluate and compare the effect of alkaline pH on the sealing ability of calcium-enriched mixture (CEM) cement and mineral trioxide aggregate (MTA) apical plugs.
Seventy single-rooted human maxillary anterior teeth were randomly divided to two experimental groups for Angelus MTA and CEM cement (n=30) and two control groups (n=5). Each group was divided into two subgroups of 15 for neutral and alkaline pH, and 1 negative and 1 positive control groups of 5. The root canals were cleaned and shaped by using ProTaper rotary system (Dentsply Maillefer; Ballaigues, Switzerland) and the terminal 3mm of the roots were resected. Then, MTA and CEM cement were condensed in apical region with 3mm thickness. The samples were exposed to two environments with different pH values of 13 and 7.4. The leakage was assessed by using the fluid filtration technique at 1, 7, 14, 30 days intervals. Data were analyzed by the repeated measures MANOVA.
There was no statistically significant difference in the rate of microleakage between neutral and alkaline pH of CEM cement and MTA (p> 0.05). The sealing ability of MTA in an alkaline pH of 13 was significantly less than CEM cement in this pH (p An environment with alkaline pH had no adverse effect on the sealing ability of MTA and CEM cement used as apical plugs. CEM cement had better sealing ability in alkaline pH.

The purpose of this laboratory study was to evaluate the effect of acidic pH on the sealing ability of calcium-enriched mixture (CEM) cement and mineral trioxide aggregate (MTA) apical plugs. Methods and Materials: Seventy single-rooted human maxillary anterior teeth were recruited. The teeth were randomly divided into 4 experimental groups (n=15), and 1 negative and 1 positive control groups of 5. The root canals were cleaned and shaped and the terminal 3 mm of the roots were resected. Then MTA and CEM cement plugs were condensed in apical region with 3 mm thicknesses. The samples were exposed to pH values of 5.5 and 7.4. Leakage was evaluated by the fluid filtration technique at 1, 7, 14, 30 day intervals. Data were analyzed by the repeated measures MANOVA, one-way ANOVA and MANOVA/Bonferroni test. Acidic pH significantly reduced the sealing ability of MTA after 1, 14 and 30 days (P<0.05). The rate of microleakage in CEM cement samples in acidic pH was significantly greater than that in neutral pH in day 30 (P<0.05). There was no significant difference between the sealing property of MTA and CEM cement at both pH levels (P>0.05). It can be concluded that the CEM cement exhibited similar sealing ability as MTA at both pH levels. In addition, an acidic pH environment reduced the sealing ability of MTA and CEM cement after 30 days.

Sealing ability of root-end filling materials is of great importance. It can be investigated by measuring microleakage. The purpose of this in vitro study was to evaluate microleakage of calcium enriched mixture (CEM) cement in two different media including phosphate buffer solution (PBS) and distilled water. Twenty single-rooted human teeth were selected. All teeth were root-end filled with CEM cement. Samples were divided into two groups of 10 each and were placed in PBS or distilled water. The microleakage was measured after 12 and 24 h, 14 and 30 days with Fluid Filtration device. Data were statistically analyzed by repeated measures test. Sealing ability of CEM cement was significantly superior in PBS compared to distilled water (P<0.05). This study also showed that time had no significant effect on the sealing ability of CEM cement. Media can significantly affect the microleakage of CEM cement. PBS can provide more phosphorous ions for hydroxyapatite formation of CEM cement; therefore, CEM cement can seal more effectively with PBS.

There are several methods for evaluating microleakage in dentistry, for example dye or bacterial leakage, electro-chemical methods, radioisotope labeling and fluid filtration. The purpose of this study was to assemble the fluid filtration system for quantitative evaluation of microleakage in dental materials. The roots were connected to a tube filled with an underwater pressure supply. A bubble was introduced into the water to measure endodontic leakage. A digital camera and professional software were utilized to record and measure the bubble displacement. Our system was constructed successfully and functioned correctly. In this pilot study we found this system efficient for the evaluation of microleakage of dental materials.