Mcmahonreimer4640

62 N) than AH Plus group (728.29 N). However, no statistical significant difference was found between the two groups (P>0.05). The greatest mean fracture force was shown in the negative control group (913.915 N) with statistical significant difference between the other three groups (P<0.05).

Gutta-percha/TotalFill and gutta-percha/AH Plus did not reinforce the root canal treated teeth.

Gutta-percha/TotalFill and gutta-percha/AH Plus did not reinforce the root canal treated teeth.

Initial setting time is one of the most important properties of calcium silicate cements (CSCs) such as white mineral trioxide aggregate (WMTA). This study aimed to evaluate the effect of two methods used to reduce the particle size of WMTA, mechanical activation and chemical synthesis.

WMTA without bismuth oxide (WMTA-B) was provided and divided into four groups (n=5) including WMTA-B, WMTA-B+10 min milling, WMTA-B+30 min milling, and sol-gel. In groups 2 and 3, the milling was performed by using tungsten carbide balls in a ratio 115 (w/w) and a vibration frequency of 30 Hz together with absolute ethanol. For the fourth group, polyethylene glycol (PEG), calcium acetate (Ca(C

H

O

)

), SiO

, and aluminum oxide (Al

O

) were used for the sol-gel process. After preparation, sample powders were mixed with distilled water and placed in cylindrical molds, covered with water-moistened gauze, and incubated at 37°C for 24 hours. The Vicat needle test analyzed the initial setting time. Data were analyzed by ANOVA and Tukey tests at a significance level of P<0.05. The correlation between particle size and setting time was determined.

Initial setting time of the sol-gel and WMTA-B+30 min milling was significantly lower than in the other two groups (P<0.05). A significant correlation was noticed between particle size and initial setting time (P<0.05).

Sol-gel process introduces a promising alternative strategy for the reduction of initial setting time of CSC materials. While both methods increased surface area, mechanical activation was not as successful in reducing surface area and initial setting time as effectively as the sol-gel process.

Sol-gel process introduces a promising alternative strategy for the reduction of initial setting time of CSC materials. While both methods increased surface area, mechanical activation was not as successful in reducing surface area and initial setting time as effectively as the sol-gel process.

The purpose of this laboratory-based study was to compare the shaping forces and torques developed by the XP Shaper (FKG Dentaire SA, La Chaux-de-fonds, Switzerland) and OneCurve (Micro-Mega, Besancon, France) systems during shaping of narrow canals.

Mandibular premolars with a single canal were divided equally into two groups; XP Shaper and OneCurve (n=16 each). In both groups, the canals were shaped with XP Shaper file (30/01) or OneCurve file (25/O6) that was inserted three times until it reached the canal length. The tooth was surrounded by water under controlled simulated intracanal temperature throughout the experiment. The inward and outward peak forces and the peak torques were recorded and analyzed statistically using the Mann-Whitney test. The shaping times were analyzed using Student's t-test. The significance level was set at 5%.

In both groups, the developed forces in both directions and the torques increased with the successive insertions of the file. In the two groups, the inward peak forces ranged from 0.33 to 3.12 N, while the outward peak forces ranged from 0.09 to 1.96 N. In the three insertions, the XP Shaper showed significantly lower peak forces in both directions. The peak torque developed in both groups ranged from 0.12 to 1.52 N.cm. XP Shaper had significantly lower torque values in all the insertions than OneCurve. The XP Shaper system was able to completely shape the canals in 33.4 seconds while the OneCurve system was able to completely shape the canals in 32.8 seconds.

The XP Shaper system showed favorably lower force and torque values during canal shaping compared with the OneCurve system.

The XP Shaper system showed favorably lower force and torque values during canal shaping compared with the OneCurve system.

The objective of this ex vivo study was to evaluate canal transportation and centring ability of Reciproc and Reciproc blue systems in curved root canals with or without prior use of PathFile rotary system (PF) using Cone Beam Computed Tomography (CBCT).

One hundred and twenty curved root canals from maxillary and mandibular premolars were selected. Canals were divided randomly into 4 groups (n=30) Reciproc 25 (R25), (PF+R25), Reciproc Blue 25 (RB25), (PF+RB 25). Specimens were scanned before and after root canal preparation. Using CBCT, root canal transportation and centring ability was assessed by measuring the shortest distance from the edge of uninstrumented canal to the periphery of the root (mesial and distal) before and after preparation. Data were analysed using a one-way analysis of variance and Tukey test. The p value was set at 0.05.

Less transportation and better centring ability occurred when PF was used before R25 or RB25 (P<0.0001). There was no significant difference between R25 and RB25 groups.

Using PF before R25 and RB25 resulted in less root canal transportation and better centring ability. The specific thermo-mechanical treatment of RB25 did not provide better results when compared to R25.

Using PF before R25 and RB25 resulted in less root canal transportation and better centring ability. The specific thermo-mechanical treatment of RB25 did not provide better results when compared to R25.

The aim of this study was to evaluate the use of Self-adjusting file (SAF) system and Hedström (H) file for removing remaining filling material (RFM) from C-shaped canals.

20 C-shaped mandibular second molars with C1 configurations were instrumented, filled with tagger´s hybrid technique. Samples were divided into 2 groups (n=10). Reciproc R25 and a Mtwo 35/04 file were used for retreatment in both groups. Then, a 2.0 SAF file (group I) and a #35 H file (group II) were used as supplementary steps for RFM removal. Micro-CT scanning was performed after every procedure. Total volumes were calculated and converted into percentages. Also, the minimum wall thickness at 3, 5, 7 mm from apex was calculated. The Prism 7.0 software was used as the analytical tool with a significance of 5%.

Initial obturation removal was approximately 64% in group I and 67% in Group II. The apical third had the highest values of RFM. The use of a H file significantly reduced the RFM compared to SAF in the total canal length respectively (30% vs 18%) and at 1-3 mm and 3-6 mm when compared to the use of SAF. A statistically significant decrease of RFM and minimum wall thickness were observed in both groups (P<0.05).

None of the retreatment techniques completely removed RFM. GSK2879552 cost The apical region was the more unaffected area. Also, the SAF file was less effective than the H file in removing the RFM. Although C-shaped canals possesses thinner dentinal wall thickness, no excessive dentine removal was observed after each instrument use.

None of the retreatment techniques completely removed RFM. The apical region was the more unaffected area. Also, the SAF file was less effective than the H file in removing the RFM. Although C-shaped canals possesses thinner dentinal wall thickness, no excessive dentine removal was observed after each instrument use.

This study aimed to investigate the root canal system morphology of maxillary first molar mesiobuccal (MB) roots in a Brazilian sub-population using micro-computed tomography.

Ninety-six MB roots were scanned with a micro-CT (Skyscan 1173, Bruker). Three-dimensional images were analyzed regarding the number of pulp chamber orifices, the number and classification of the canals, the presence of accessory canals in different thirds of the root as well as the number and type of apical foramina.

A single entrance orifice was found in 53.0% of the samples, two in 43.9% and only 3.1% had three orifices. The second mesiobuccal root canal (MB2) was present at some portion of the root in 87.5% of the specimens. A single apical foramen was present in 16.7%, two in 22.9%, and three or more foramina in 60.4% of the roots. Only 55.3% and 76.1% of the root canals could be arranged by Weine's and Vertucci's classifications, respectively.

The number of orifices at the pulp chamber level could not work as a predictor of the MB2 presence. The most prevalent canal configuration was Weine type IV / Vertucci type V. The anatomical complexity of the MB root could not be entirely classified by the current most accepted classifications.

The number of orifices at the pulp chamber level could not work as a predictor of the MB2 presence. The most prevalent canal configuration was Weine type IV / Vertucci type V. link2 The anatomical complexity of the MB root could not be entirely classified by the current most accepted classifications.

This study aimed at exploring the usage of radiographic image-enhancement tools in Saudi dental practice when interpreting radiographs taken for root-canal-treatments' (RCTs) procedures and the influencing factors.

An online survey including questions related mainly to the usage of images enhancement tools and the reasons for no or low frequently usage was constructed. The survey was sent to 550 general dentists (GDs), randomly selected from the Saudi Dental Register, and all endodontists (185) in Saudi Arabia using the Google-Drive tool. A reminder email was sent two months later to encourage none-respondents to complete the survey. Data were analyzed using the Chi-square and Linear-by-Linear Association tests at p=0.05.

While the highest percentage of GDs (48.3%) never used the colour-coded tool, the highest percentage of endodontists (46.1%) used it sometimes (P<0.001). The majority (84.2%) used the contrast tool either generally (67.8%) or sometimes (16.4%) (P<0.001); with more endodontists (7reasons for not using the tools reported by GDs and endodontists, respectively. Further studies are required to determine the exact application for each tool and to investigate the impact of all image-enhancement tools on their diagnostic accuracy.

The contrast and magnification were the most common used image-enhancement tools in Saudi dental practice. Endodontists reported greater preferences on using all images-enhancement tools than GDs. Unawareness and lack of time were the dominant reasons for not using the tools reported by GDs and endodontists, respectively. link3 Further studies are required to determine the exact application for each tool and to investigate the impact of all image-enhancement tools on their diagnostic accuracy.

To report usage of full-digital-radiography (FDR) during root-canal-treatments (RCTs) in Saudi dental-practice and to explore factors and measures that obstacle/contribute to better implementation.

Following a pilot study, questions on demography, types of radiographic systems used during RCTs, advantages and disadvantages of FDR, reasons of not using it and measures that increase its implementation were included. The sample size was calculated considering the total number of general dentists (GDs) in Saudi Arabia and a 50-60% expected response rate. The questionnaire was emailed to 550 GDs and all endodontists in Saudi Arabia (185). A solo a reminder was emailed two months later. Data were analyzed by the Chi-square test at P=0.05.

Most participants (64.9%) used FDR for RCTs (P<0.001); with all endodontists (100%) and 52% of GDs (P<0.001). While all who were working in governmental-academia (100%) used FDR, 69.2% in private-academia did so (P<0.001); with no difference between private and governmental-clinics (60.