O Glide Path na Endodontia Contemporânea: Revisão de Literatura / The Glide Path in Contemporary Endodontics: Literature Review

Por meio deste estudo é possível analisar que a instrumentação dos canais radiculares após o uso do Glide Path traz inúmeros benefícios, incluindo o melhor deslizamento dos instrumentos, redução do número de fraturas e menor intercorrências intrarradiculares. Além disso, essa preparação inicial do canal radicular com o uso do Glide Path realiza uma desobstrução, criando um “caminho” livre para o melhor deslize dos instrumentos no canal radicular. Os instrumentos possuem características e particularidades que levam ao mesmo objetivo de preparar o conduto para uma segura instrumentação, destaca-se aqui o WaveOne Gold, R-Pilot e o PathFile. É uma técnica que vem sendo difundida e utilizada na endodontia contemporânea com o intuito de realizar um procedimento eficaz.---Abstract: Analyze the use of instruments to prepare the Glide Path and understand how this endodontic instrument brought advantages in instrumentation techniques. This is a literature review with selected articles from the last 10 years, in order to achieve the objectives proposed by the theme. Articles in English and Portuguese were used, with all information pertinent to the topic extracted. Through this study, it is possible to analyze that the instrumentation of root canals after the use of the Glide Path brings numerous benefits, including better sliding of the instruments, reduction in the number of fractures and less intra-radicular complications. In addition, this initial preparation of the root canal using the Glide Path performs clearance, creating a clear “path” for the best glide of the instruments in the root canal. The instruments have characteristics and particularities that lead to the same objective of preparing the conduit for safe instrumentation, the Wave One Gold, R-Pilot and PathFile stand out here. It is a technique that has been disseminated and used in contemporary endodontics with the aim of performing an effective procedure. Through this bibliographical study, it is possible to consider that the use of the Glide Path favors the preparation of the root canal and proves to be effective and safe when used before instrumentation, thus, with the creation of a more favorable environment for instrumentation, the chances of success in endodontic treatment.

Improving Lidar Windshear Detection Efficiency by Removal of “Gentle Ramps”

The Doppler Lidar windshear alerting system at the Hong Kong International Airport (HKIA), the first of its kind in the world, has been in operation since 2006. This paper reports on an enhancement to the automatic windshear detection algorithm at HKIA, which aims at filtering out alerts associated with smoother headwind changes spread over longer distances along the aircraft glide path (called “gentle ramps”) which may nonetheless exceed the well-established alerting threshold. Real-time statistics are examined over a 46-month study period between March 2016 and December 2019, covering a total of 2,017,440 min and over 1500 quality-controlled pilot reports of windshear (PIREP). The “gentle ramp removal” (GRR) function is able to effectively cut down the alert duration over the 5 major runway corridors, inclusive of both landing and take-off, which together account for over 98% of the PIREP received at HKIA during the study period. In all 5 runway corridors this is achieved with a proportionately smaller decrease—even with no changes in 2 cases—in the hit rate, highlighting the efficiency of the GRR function. The difference in statistical behaviour across the runway corridors also echo literature findings about the differences in length scale of wind disturbances at different locations within HKIA. This study serves as a unique documentation of the state-of-the-art in operational Lidar windshear detection and can provide useful reference to airports and aviation meteorologists around the world.

Comparison of Canal Transportation and Centering Ability of One-G, EdgeGlidePath, and Neolix: A MicroComputed Tomography Study of Curved Root Canals

Aims. A glide path is created prior to root canal instrumentation by nickel-titanium (NiTi) rotary files to increase the efficiency and safety of cleaning and shaping. This study aimed to assess root canal transportation in use of different glide path files in curved canals. Materials and Methods. 30 sound mesiobuccal root canals of mandibular molars with 20° to 40° curvature were selected and randomly assigned to 3 groups of EdgeGlidePath (EGP, EdgeEndo), One-G (Micro-Mega), and Neolix (Neoniti). The specimens were scanned before and after glide path creation by microcomputed tomography (micro-CT). The pre- and postoperative micro-CT scans were superimposed, and the degree of canal transportation and centering ratio were measured at 1, 3, 5, and 7 mm distances from the apical foramen. Statistical Analysis. The data were analyzed by two-way and one-way ANOVA. Results. The effects of distance from the apical foramen and instrument type and the interaction effect of the two were not significant on the centering ability of the files or canal transportation. Conclusion. EdgeGlidePath, One-G, and Neolix files fabricated from the conventional NiTi alloy or heat-treated M-Wire alloy showed similar performance regarding centering ability and canal transportation in glide path preparation in curved canals.

Alteration in surface roughness of reciprocating endodontic instruments

Background: Surface roughness is one of the most important characteristics of endodontic instruments, correlating to instrument fracture. The purpose of this study was to measure the surface roughness values of these instruments before and after resin root canal preparation without previous glide path preparation, with the new method. Data was obtained from field emission scanning electron microscopes (FE-SEM) combined with independent ImageJ software (NIH, Bethesda, MD, USA). Methods: A total of 20 simulated J-shape resin blocks with a radius of 4.5 mm, length of 16 mm, and angle of inflection of 600 were chosen and distributed into two equal groups. Each group was prepared by the WaveOne Gold Primary (Dentsply Sirona, Maillefer, Ballaigues, Switzerland) or the Reciproc Blue R25 (VDW, Munich, Germany) instruments, without glide path preparation. Special molds were used to confirm the same areas on the cutting blade at 3 mm and the instruments’ tips were scanned by FE-SEM, at different observed times. The parameters of Ra, Rq, and Rz in each sample were collected using the ImageJ software for analyses. The data was processed using the paired t-test with a significance level of 0.05. Results: Right after the first resin canal instrumentation, the surface roughness parameters of the two reciprocating investigated instruments were decreased. Conclusions: The FE-SEM images processed using the ImageJ software offered a trustworthy and suitable method for assessment of the NiTi endodontic file surface roughness.