Objectives. This study aimed to validate the accuracy of working length (WL) measurements obtained with the newly introduced Propex IQ apex locator and to compare it with the latest generations of other electronic apex locators, CBCT, and conventional periapical radiographs by using the actual WL measurements obtained by using an endodontics microscope as a reference. Materials and Methods. Thirty-five extracted single-rooted human mandibular first premolars with curvatures from 10° to 20° were selected according to the inclusion and exclusion criteria and cut at the cementoenamel junction to achieve a standard reference point for WL determination. The actual WL was obtained by inserting a size-15 k-file in the root canal until the tip of the file was visible under an endodontic microscope. The definitive WL was measured using Propex IQ (Dentsply Sirona), Raypex 6 (VDW Dental), Root ZX (Morita), and Apex ID (Kerr Dental). In addition, radiographic WL was obtained using periapical radiographs and CBCT. One-way ANOVA was used for comparisons of the WL values, with a value < 0.05. The percentage of success of each method for determination of the definitive WL was assessed using cross-tabulation and chi-square tests. Results. CBCT radiographs and Propex IQ apex locator yielded the most accurate WL measurements in comparison with the actual WL measurements ( ). Raypex 6, Root ZX, and Apex ID yielded more accurate WL measurements than conventional periapical radiographs ( ). Periapical radiographs yielded the least accurate WL measurements in comparison with the actual WL values ( ). Conclusions. Within the limitations of this study, the Propex IQ apex locator showed higher accuracy than Raypex 6, Root ZX, and Apex ID for WL determination in the root canal. Nevertheless, CBCT radiographs yielded the maximum accuracy for WL measurements.

Objectives. Particle size and shape can influence the properties of materials. However, to improve the physicochemical and biological properties of mineral trioxide aggregate (MTA), silicate‐based hydraulic cements were introduced. This study aimed to evaluate and compare the major constituents and crystalline structures along with the surface morphology of different types of calcium silicate‐based cement (CSC). Materials and Methods. Six different types of CSC (white Portland cement, white ProRoot MTA, white MTA Angelus, Biodentine, and Endosequence, both putty and paste) were used in this study. Five samples of each material were analyzed in both uncured and cured cement using scanning electron microscopy/energy‐dispersive X‐ray (SEM/EDX), X‐ray diffraction (XRD), and Fourier transform‐infrared spectroscopy (FTIR). Results. SEM analysis showed that the surfaces of all materials consisted of particle sizes ranging from 0.194 μm to approximately 51.82 μm. The basic elements found in both uncured and cured cement of all tested materials using EDX were carbon, calcium, silicon, and oxygen. A difference was observed in the presence or absence of magnesium, aluminum, bismuth, zirconium, and tantalum. XRD showed that all tested materials were composed mainly of tricalcium silicate and dicalcium silicate, which are the main components of Portland cement. FTIR analysis showed aromatic rings, phosphine PH, alkyl halides, and alcohol O‐H groups in all tested materials but at different wavenumbers. Conclusions. The different types of CSCs tested in this study were primarily modified types of Portland cement with the addition of radiopacifiers. ProRoot MTA and MTA Angelus contained bismuth oxide, Biodentine contains zirconium oxide, whereas Endosequence root repair materials (both putty and paste) contained zirconium oxide and tantalum oxide. Endosequence root repair materials showed smaller particle sizes than the other groups. White PC had the most irregular and large particle sizes. CSC had a smaller particle size, except for MTA Angelus. Clinical Relevance. The composition of CSC has a direct influence on the properties of these cements, which may affect the clinical outcome of the treatment.

The effectiveness of remineralizing agents in reducing dentine permeability by tubule occlusion using fluid filtration device functioning at 100 cmH₂O (1.4 psi) pressure and SEM/EDX analysis were evaluated and compared. Seventy (n = 70) dentine discs of 1±0.2 mm width were prepared from sound permanent human molars. Fifty (n = 50) dentine discs were randomly divided into 5 groups (n = 10): Group 1: GC Tooth Mousse Plus (Recaldent GC Corporation Tokyo, Japan), Group 2: Clinpro™ White Varnish (3M ESPE, USA), Group 3: Duraphat® Varnish (Pharbil Waltrop GmbH, Germany), Group 4: Colgate Sensitive Pro-Relief™ dentifrice (Colgate Palmolive, Thailand), and Group 5: Biodentine™ (Septodont/UK). Dentine permeability was measured after treatment application at 10 minutes, artificial saliva immersion at 7 days, and citric acid challenge for 3 minutes. Data were analyzed by two-way repeated measures ANOVA. Dentine specimens (n = 20) were used for SEM/EDX analyses to obtain qualitative results on dentine morphology and surface deposits. Each treatment agent significantly reduced dentine permeability immediately after treatment application and created precipitates on treated dentine surfaces. All agents increased permeability values after 7 days of artificial saliva immersion except Clinpro White Varnish and Biodentine. Clinpro White Varnish exhibited significant resistance to acid challenge compared to others. Colgate Sensitive Pro-Relief dentifrice has a dual mechanism of action in reducing the dentine sensitivity.

Purpose: This study aims to retard the setting reaction of CSC by mixing it with 2% chlorhexidine gel (CHX) which will be used as an intracanal medicament, and to evaluate the removal of the experimental medicaments from the root canal. Materials and Methods: White Portland cement, white ProRoot MTA and Biodentine were mixed with 2% CHX. The setting time, flowability and film thickness of the CSC/CHX mixture (experimental medicaments) were assessed and measured following the standards of ISO specification. Calcium ion release was measured using ICP-OES, while pH was tested using a pH meter. Moreover, twenty single-rooted teeth were filled with the experimental medicaments for seven days, then the medicaments were removed and the samples analyzed using SEM. Calcium hydroxide paste was used as a control. Results: The setting time of the experimental medicaments was inhibited until 84 days. The calcium ion release of the experimental medicaments was significantly higher compared to the control over the period of 14 days (P< 0.001). The mean pH value was above 11.45 for all tested materials over a period of 14 days, with no significant difference between them (P< 0.05). There was no significant difference in film thickness of the experimental medicaments compared to the control (P> 0.05). However, the flowability of the experimental medicaments was significantly higher than the control (P< 0.05). SEM showed no significant differences in the removal of the intracanal medicaments between all the tested groups. Conclusion: The addition of 2% CHX to CSCs retarded or inhibited its setting reaction over a period of 84 days. The calcium ion release and flowability of these experimental medicaments was found to be better than calcium hydroxide. Removal of the intracanal medicaments from the root canal was successfully achieved in all groups. Therefore, these experimental medicaments have the potential to be used as an enhanced root canal medicament.

Objective: This study aimed to examine the shaping ability of six rotary and reciprocating file systems, as well as hybrid techniques in simulated S-shaped root canals.Methods: A hundred and twenty S-shaped radiopaque thermosetting epoxy resin blocks were grouped according to the system used for biomechanical preparation. Six groups of 15 canals each were prepared using TruNatomy, Procodile, VDW Rotate, Hyflex CM, OneCurve, and WaveOne Gold, respectively. Two additional hybrid (Procodile/Hyflex CM and Procodile/TruNatomy) groups (n=15 each) were added after evaluating the results of individual systems. All canals were enlarged to 0.25 mm apically. Canal transportation, centering ability, diameter increase, and iatrogenic errors were assessed by superimposed pre-operative and post-operative images. AutoCAD was used for data analysis. All groups were statistically compared with analysis of variance and Tukey honest significant difference test (p