Background: Nickel-titanium rotary files with thermomechanical treatment were developed to allow greater flexibility when instrumenting the root canals. The instruments allowed operators to deal with duct curvatures more easily. Manufacturers are trying to produce files that work better efficiently and safely. Knowing the properties of marketed files is especially important in helping you choose an appropriate file system. The objective of this study was to evaluate the flexibility of three different nickel-titanium (NiTi) files with thermomechanical treatment at two different points along the file. Materials and methods: The flexibility of three NiTi files with thermomechanical treatment (Protaper Gold, 2Shape and V-Taper Fanta Gold) was measured. Each file was clamped at 3 mm and 7 mm (n = 10 / length / file) and a universal testing machine was used to bend the files to a maximum stren...

The objective of this research was to compare the solvent action of orange oil, eucalyptol and experimental lemongrass oil on gutta-percha cones for cold technique and thermoplastic technique. Methodology: The sample consisted of 80 gutta-percha cones No. 80 Endomedic and F3 ProTaper Universal. The cones were divided into 4 groups (n = 20) according to the type of solvent, and each one was divided into two subgroups (n = 10) according to the exposure time (5 min and 10 min). The cones were immersed in the respective solvent for 5 or 10 minutes. Then, they were washed with 5 ml of alcohol for 5 minutes and rinsed with water. Finally, after drying at room temperature for one hour, the solvent action was recorded in grams (g) of weight loss. The results were analyzed and compared using Tukey's test (p<0.05). Results: The Endomedic cone exposed for 5 min to eucalyptol obtained the lo...

Objective: The purpose of this study was to determinate the bacterial contamination of Beta (β) gutta-percha cones at 0, 24, 47 and 72 hours of the different supplies of the Universidad Científica del Sur, Lima 2020. Materials and Methods: 16 β-type gutta-percha cones were obtained of sealed packages under aseptic measurements, they were placed in vials with 2ml BHI and subsequently planted in BHI agar plates as well as in selective medias as Salted mannitol agar and MacConkey agar after 24 hours of incubation at 37 ° the plates were read and  count in CFU , the same procedure was performed for the other times evaluated 24, 48 and 72 hours, giving a total of 64 β-type gutta-percha cones. Results: It was observed that the level of bacterial contamination was the same among the different supplies in all the establish times of in this study 0, 24, 48 and 72 hours. Therefore, there...

External cervical resorption is a pathological process, with an etiology that is not completely understood. Possible predisposing factors are orthodontic treatment, trauma, internal whitening, bruxism, etc. Internal whitening is an effective and minimally invasive method for the whitening non-vital teeth. This method is associated with a risk of resorption, which if not treated, can lead to tooth loss. This case report describes the management of two upper incisors with external cervical resorption, with a previous history of root canal treatment and internal whitening.