Objective: The objective of this study is to evaluate and compare the shaping ability of ProTaper Next (PTN) and Navigator EVO (N-Evo) rotary file systems in L- and S-shaped simulated resin root canals. Materials and Methods: A total of forty L-shaped (n = 20) and S-shaped (n = 20) resin block root canals were randomly assigned into four groups (n = 10) based on the PTN and N-Evo rotary file systems. Before the instrumentation, simulated root canals were filled with the India blue ink and preinstrumentation images were taken using a digital camera. Each canal was prepared to the standard working length 16 mm, 0.15 mm apical foramen diameter, and 0.2 initial tapers. After the canal preparation, red India ink was filled in each canal and postoperative images were obtained. The two images were superimposed, five points were selected, and canal widths were measured with image analysis software. Canal preparation time, file failure, and presence of aberrations were recorded and compared between the two systems. Descriptive statistics of mean and standard deviation and inferential statistics of Independent samples t-test and analysis of variance tests were applied to the data. Results: PTN file system showed significantly lesser preparation time (L-shape, 2.55 ± 0.38 min, and S-shape, 2.57 ± 0.44 min) in comparison to N-Evo file system (L-shape, 5.01 ± 0.37 min, and S-shape, 5.21 ± 0.30 min) (P < 0.001). N-Evo file removed significantly less resin in many positions and exhibited lesser canal straightening in both S- and L-types of canals compared to the PTN file system (P < 0.05). Both file systems created danger zone and outer widening of the canal. Three N-Evo files fractured in L-shaped canals. Conclusions: N-Evo file system demonstrated better shaping ability compared to PTN in L- and S-shaped simulated canals. PTN file system prepared the canal in less time and maintained the original curvature. An almost similar number of canal aberrations found between tested file systems. However, three N-Evo files broke in L-shaped canals indicating possible limitation in this area.

Purpose: The purpose of the research was to quantify the expressions of substance P (SP) in sensory nerve cells contained in the dental pulp of Wistar rats following the application of Escherichia coli lipopolysaccharide (LPS). Materials and Methods: Forty-two male Wistar rats were divided into six groups (n = 7): Groups C1 and C2 received no treatment and served as negative controls; Groups C3 and C4 only had cavity preparation; and Groups T1 and T2 received cavity preparation and treated with LPS. All teeth were subjected to immunohistochemistry analysis of SP expression at 24 h (C1, C3, and T1) and at 72 h (C2, C4, and T2). Results: There was a significant increase in the SP of the T1 group compared to the C1 and C3 groups and of the T2 group compared to the C2 and C4 groups. While there was no significant difference in the expression of SP between the C1 and C2 groups, a significant increase was found in T1 group compared to that of the T2 group and in the C3 group compared to the C4 group (P < 0.05). Conclusion: The application of LPS to teeth resulted in the highest expression of SP after 24 h which then decreased after 72 h.

Aim: This study was aimed to determine the use of calcium hydroxide (Ca(OH)₂) intracanal medicament effect on the push-out bond strength of RelyX Unicem self-adhesive cement onto the root canal wall. Materials and Methods: A total of 50 extracted human maxillary permanent incisor teeth were randomly divided into control and experimental groups (n = 25 for each group). The control group was prepared for routine root canal treatment followed by post space preparation. RelyX Unicem self-adhesive cement is used for the cementation of fiber post in the root canal, as in experimental group, Ca(OH)₂intracanal dressing was placed into the root canal for a week, followed by root canal filling, post space preparation, and cementation of fiber post using RelyX Unicem cementation. Each sample was divided into coronal, middle, and apical root sites. They were horizontally sliced and examined using scanning electron microscope (SEM). Three slices from each of the three sites were subjected to push-out test for bond strength measurement. Independent t-test was used to compare the push-out bond strength of RelyX Unicem on the root canal wall. One-way analysis of variance and pairwise comparison test were used for the statistical analysis. The significant level was set as P < 0.05. Results: The significant differences in bond strength were demonstrated between the different sites of the root, where the coronal and apical with the P value 0.031 and 0.020, respectively. However, the middle third of the root showed no statistically significant difference, where P = 0.072. Conclusions: Intermediate Ca(OH)₂dressing has an effect on the bond strength of RelyX Unicem self-adhesive resin cementation on the root canal wall.

Aim: An in vitro evaluation of the antimicrobial efficacy of 5% sodium hypochlorite (NaOCl), 2% chlorhexidine (CHX), and herbal extracts of neem and Aloe vera in disinfection of gutta-percha cones for 3 min. Materials and Methods: Ninety gutta-percha cones were used for the study. They were divided into four groups (Group A, Group B, Group C, and Group D) based on the decontaminant used. Each group had 20 cones which were further divided into two subgroups. The microbial species used were Enterococcus faecalis and Staphylococcus aureus. Ten cones in each subgroup were contaminated with E. faecalis and S. aureus, respectively. From the remaining 10 cones, five were contaminated with E. faecalis and five with S. aureus and were disinfected with normal saline which was used as a control. These concentrated extracts were obtained using Soxhlet extraction procedure and were tested for their antimicrobial efficacy by counting the colony-forming units (CFU). The count was taken on day 0 (immediately after disinfection) and day 7 (after incubation for 7 days) for each organism. Results: The number of CFU on day 0 was not more than five for both E. faecalis and S. aureus for all the disinfectants used. However, on day 7 after incubation, only the neem group showed full growth of colonies for the E. faecalis. Conclusion: Long-term effects of A. vera were found to be superior and comparable to 5% NaOCl and 2% CHX. However, the long-term effect of neem as a disinfectant for gutta-percha needs further investigation.

Aim: The aim of this study was to compare the cyclic fatigue resistance of endodontic files of different manufacturers operated in disparate motions. Materials and Methods: Six different brands of nickel–titanium instruments, such as ProFile Vortex™, Vortex Blue™, Twisted File™, HyFlex™, WaveOne™, and S1™ all with a tip size ISO 25 with 0.06 taper, except for WaveOne™ tip size ISO 25 with 0.08 taper, were included in the study. Six groups of 20 rotary files from each system were tested for cyclic fatigue resistance. All files were rotated in a simulated root canal with a certain diameter, angle of curvature, and a radius of curvature of a specific cyclic fatigue testing device until fracture occurred. Time to fracture was recorded for each instrument in each group in seconds. The mean values and standard deviation were then calculated. Data were compared using repeated measures ANOVA for individual comparisons followed by Bonferroni's correction for multiple comparisons. Significance was set at the 95% confidence level. Results: Time of fracture had statistically significant differences among all groups tested (P < 0.5) except between Group 1 (PV) and Group 4 (HF) and between Group 2 (VB) and Group 3 (TF); there was no statistically significant difference (P > 0.5). Thus, the S1 file offered a long life span, followed by WaveOne™, ProFile Vortex™, HyFlex™, Twisted Files™, and then Vortex Blue™. Conclusion: The reciprocating instruments (S1 and WaveOne™) had a higher cyclic fatigue resistance than all rotary files used in this study. However, the Profile Vortex (M-wire) and HyFlex (CM) showed better cyclic fatigue resistance than other rotating files in this study. Hence, the blue and R-phase heat treatments did not enhance the cyclic fatigue resistance for rotating instruments.

Objective: The aim of this study was to compare the degree of crown discoloration induced by a novel bioceramic and conventional endodontic sealers. Materials and Methods: Thirty extracted maxillary central incisors were selected and randomly divided into three groups (n = 10), according to the assigned sealer: G1 – TotalFill, G2 – Apexit Plus, and G3 – AH Plus. Baseline color of the labial surfaces was obtained using a spectrophotometer. Standardized root canal preparation and obturation were completed using ProTaper system and gutta-percha with sealer cement. Access openings were sealed using light-cured resin composite. Specimens were stored in saline and placed in an incubator at 37°C until testing. Crown color was reassessed after 1 week, 1 month, and 3 months. Color change from baseline was calculated using the following equation: ΔE* = ([ΔL*]² + [Δa*]² + [Δb*]²)½. Data were analyzed using ANOVA, t-test, and Tukey post hoc test (at P≤ 0.05). Result: In the three groups tested, the highest mean value of color change was found after 3 months, whereas the lowest was at 1 week. Changes were significant in all groups (P < 0.001 in G1 and G2, P= 0.009 in G3). At all assessment times, no significant difference was found between the three groups of sealers tested (P = 0.593, P= 0.185, and P= 0.33 at 1 week, 1 month, and 3 months, respectively). Nevertheless, G1 showed the highest and G3 the lowest color changes at both 1 and 3 months. Conclusion: It was concluded that all sealers tested result in a measurable and gradual tooth color change. While the bioceramic sealer resulted in a slightly higher color change compared to calcium hydroxide- and resin-based sealers, the difference was not considerable.

Aim: The aim of the study is to determine the techniques and materials used by South African dental practitioners who perform endodontic treatment in private practice and evaluate their compliance to the 2006 European Society of Endodontology (ESE) quality guidelines. Materials and Methods: An online survey was distributed to all dentists registered with the South African Dental Association (n = 3191) and prosthodontists registered with the Academy of Prosthodontics (n = 61), practicing in South Africa. Fourteen subject areas related to endodontic materials and techniques were assessed. Responses were evaluated using simple descriptive and analytical statistics. Results: The overall response rate was 7% (n = 215/3252; specialist prosthodontists 18% and general dentists 6%). Sixty-three percent of respondents (n = 122/193) did not routinely use rubber dam. The use of rubber dam and magnification was positively correlated with postgraduate endodontic qualifications (P < 0.05). Antibiotic prescription for irreversible pulpitis without systemic involvement was reported in an average of 31% of cases. Formaldehyde-containing sealers were used by 5% (n = 9/193). The majority of respondents (89%, n = 171/191) used sodium hypochlorite as a primary irrigant. Cold obturation techniques (82%, n = 159/193) were preferred over warm techniques (18%, n = 34/193), with the single-cone technique the most popular (58%, n = 112/193). Almost half preferred steroid-containing medicaments (48%, n = 92/193). Conclusion: Surveyed practitioners largely complied with the 2006 ESE guidelines. Notable exceptions including low rubber dam use, inappropriate antibiotic prescription, and the continued use of formaldehyde-containing medicaments and sealers were reported. Improved compliance to established guidelines may be achieved through the use of these results when planning ducational activities.

Aim: This study aimed to compare the fracture resistance of endodontically treated premolars restored by alkasite cement (Cention N), composite resin, and glass ionomer cement (GIC). Materials and Methods: Fifty freshly extracted mandibular and maxillary premolars with typical morphology were selected and mounted on acrylic cylinders. Five groups were made with ten teeth in each group as follows: Group A: intact teeth with no restoration (control); Group B: unfilled teeth with prepared mesio-occluso-distal (MOD) cavity; Group C: teeth with MOD cavity restored with nanohybrid composite; Group D: teeth with MOD cavity restored with type IX GIC; and Group E: teeth with MOD cavity restored with Cention N. Root canal treatment was done for groups B, C, D, and E after MOD cavity and before placement of the coronal filling. The specimens were mounted on a universal testing machine, and load was applied until the specimen fractured. The values were tabulated and subjected to statistical analysis. Results: The mean value of fracture resistance was highest in Group A (2015 N) followed by Group C (1504 N) and Group E (1319 N). Groups D and B showed the lowest reading. However, there was no statistical difference between Groups C and E. Conclusions: Within the limitations of the study, it can be concluded that composite is the material of choice for restorations in endodontically treated tooth. Alkasite cement can be used as an alternative to composite resin due to ease of manipulation.

Aim: The aim of this study was to evaluate the root canal preparation abilities of two nickel–titanium (NiTi) instrument systems, namely WaveOne (WO) and ProTaper Next (PTN), using cone-beam computed tomography (CBCT), on human extracted teeth. Materials and Methods: Eighty mesiobuccal root canals of the maxillary and mandibular first molars with a curvature of 10°–39° were chosen. CBCT images were captured before instrumentation using special silicone molds to ensure that the teeth are positioned at the same place before and after instrumentation. The root canals were divided into two groups, namely Group 1 and Group 2 (40 root canals in each group with similar root canal curvatures). Group 1 and Group 2 were prepared using WO and PTN, respectively. Teeth were inserted again into the previous silicone molds at the right positions. Postinstrumentation CBCT images were captured with the same parameters. Pre- and postinstrumentation CBCT images were analyzed using Invivo 5 software provided by the CBCT machine manufacturer. Results: There was no difference between the two groups of root canals instrumented by two NiTi instrument systems in root canal transportation, centering ratio, straightening, and volume changes (P > 0.05). Conclusions: Both NiTi instrument systems can be used effectively and safely in root canal instrumentation.

Effective and successful endodontic treatment requires dentists to have adequate information on the clinical variations in root canal anatomy. The maxillary first premolars usually have two roots; however, rarely, the occurrence of three root canals has been reported. Existence of such variations should be considered and noted, to be managed well and not missed. Herein, we illustrate the diagnosis and clinical management of four clinical cases presented with three root-canaled maxillary first premolars.

A case of 51-year-old female reported with pain of failed root canal treatment of the mandibular right second premolar. Periapical lesion, mobility, and deep periodontal pocket were detected during examination. Intentional replantation was discussed with the patient. The tooth was atraumatically extracted followed by root end resection and retrograde cavity preparation and filling with MTA. Curettage in conjunction with irrigation of the alveolus was considered to eliminate the inflammatory tissue. The tooth was replanted back into its socket and splinted to the adjacent tooth. The total extraoral treatment time was ≤15 min. One- and three-month follow-up revealed no clinical symptoms and progressive periapical healing. After 2 years and 7 months, complete periapical healing was evident. The success rate of intentional replantation is very promising when the procedural techniques are applied properly.

Autotransplantation of teeth is an option, which is not often taken into account by dentists, for managing early loss of teeth. It is a possible less-cost viable alternative to dental implantation when the case is well selected, and the surgical procedures are properly performed. This case report presents a 15-year-old female with infected badly destroyed mandibular right first molar making it nonrestorable. The maxillary left third molar was selected and evaluated for compatibility as a donor's tooth. Subsequently, atraumatic extraction of the compromised tooth, debridement, and disinfection along with preparation of its socket and transplantation of the donor's tooth into the receiving site was done. Radiological and clinical follow-up shows treatment success for 4 years without any considerable complications or patient's complaints. Immediate autotransplantation of tooth satisfactorily restored the functional condition of the patient, principally after good healing of periodontal and pulp tissues.

Cone beam computed tomography (CBCT) imaging can be used as a reliable aid to identify root canal system configurations and guide their treatment. The aim of this case report is to describe the root canal treatment of maxillary first molar with an unusual morphology diagnosed by CBCT. The tooth had a canal that started with a single canal orifice and ended with two apical foramina.