فهرست مطالب ali hamedi

In endodontics, glide path creation has been extensively considered a mandatory clinical step to improve the safety and efficiency of rotary nickel–titanium instruments. The high anatomic variations in the mesiobuccal (MB) root of the maxillary molars are observed in the form of canal configuration, number, and position.The aim of this study was to evaluate the negotiability of MB canals in maxillary molars using different pathfiling systems (ProGlider, R‑pilot, HyFlex electrical discharge machining [EDM], WaveOne Gold Glider, and C‑Pilot).

This in vitro study included 125 maxillary first molars with closed apex. Before preparation, all teeth were scanned by periapical radiograph for review of the presence of second MB (MB2) canals, without any resorption or calcification, and moderate curve of MB root canal. Subsequently, the access cavity was prepared with a Diamond Fissure Bur. Then, the samples were divided into five groups (ProGlider, R‑pilot, HyFlex EDM, WaveOne Gold Glider, and C‑Pilot). Certain relevant indices were recorded for analysis, such as the negotiability of the glide path file in the MB canals, file fracture rate, and negotiation speed. The level of significance P value was set at 0.05.

In this study, HyFlex EDM was the only path file that could not reach the full working length (WL) in some cases. The highest frequency of file fracture in the MB2 was observed with HyFlex EDM (24%); nevertheless, R‑Pilot presented an intermediate fracture rate (16%), and both ProGlider and WaveOne Gold Glider were the safest files (4%) in this regard. However, there were no significant differences between the groups (P = 0.065). The lowest and the highest average time of reaching full WL was observed with WaveOne Gold Glider and HyFlex EDM; nonetheless, there was no significant difference between the four rotary groups. The average number of pecks in HyFlex EDM was significantly higher in comparison to those reported for WaveOne Gold Glider and ProGlider.

Path files used for glide path preparation in the MB2 canals of maxillary molars should be flexible with low taper. The use of HyFlex EDM in the MB2 canals is not recommended due to its high taper.

Missed canals pose a potential risk in the treatment of teeth with anatomical variations, even when multi-angled radiographs have been used. Incomplete mechanical and chemical debridement of the root canal system can lead to treatment failure. Therefore, clinicians must have adequate knowledge of normal root canal systems as well as any possible variations in order to prevent any failure during or after the treatment of teeth with anatomical variations. Any case report of such rare variations would add to this critically required body of knowledge. The current case report presents the diagnosis and endodontic treatment of a maxillary first premolar with one root and three canals (one palatal and two buccal canals, all buccolingually positioned, bifurcating in the apical region), which was different from premolars with 3 canals reported up to now. This configuration describes an unusual root canal system for the maxillary first premolar and does not fit into any of the well-known root canal classification systems.

Paresthesia can result from some post-endodontic problems, including bacterial infections or mishaps which occur during the cleaning, shaping, and filling of the root canal. There are pharmacological and instrumental methods for the treatment of paresthesia; however, if presenting symptoms are suggestive of nerve injury, surgical approaches, such as intentional replantation, could be considered. In this case report study, we treated paresthesia that had occurred after endodontic treatment using intentional replantation. This case report describes the use of intentional replantation of a mandibular premolar as a successful technique to treat paresthesia involving the lower lip.

Our article aimed to present a curious case of a mandibular premolar with a C-shaped root canal and to review the available literature on this anatomical variation. Mandibular premolar teeth account for the greatest endodontic challenges in the course of treatment on account of the morphological variations in their root canal systems, including extra root(s)/canal(s) or a C-shaped configuration. A 20-year-old female patient was referred to the Department of Endodontics of Mashhad Faculty of Dentistry, suffering from abscess, and pain while chewing. On examination the culprit was found to be the left mandibular first premolar. Following special tests and periapical radiography, we found an amalgam restoration proximate to the non-vital pulp chamber, as well as an unusually complex root canal anatomy with periapical radiolucency. A non-surgical root canal treatment with the aid of a dental operating microscope was considered as the treatment plan. Clinicians should always anticipate the presence of a C-shaped configuration in mandibular premolars, and make use of all the available tools to locate and treat such cases. A substantial knowledge of root canal anatomy would be prudent to ensure a successful outcome ensuing surgical and non-surgical root canal treatments.

The errors in the preparation such as change in canal curvature especially in curved canals almost always happen in the preparation step. Nickel- titanium rotary files that have been designed for canal preparation can reduce these problems. Preparation time is also important in root canal therapy and a rotary system which can prepare the canal in a lesser time, is more appropriate. The purpose of this study was to compare the curvature change of canal after preparation and instrumentation time in three rotary system; Reciproc, ProTaper and ProTaper Next. Forty-five resin blocks were used in this study. Each canal had a curvature of 25o to 35o and 15 mm length. Pre-instrumentation images of all blocks were taken with stereomicroscope and blocks were divided into three groups and each group was prepared with one of these systems: Reciproc, ProTaper and ProTaper Next. Post-insrtumentation images of all blocks were as well taken and the canal images were overlapped, and the curvature change of canal after preparation was measured. Active instrumentation time was also calculated during the preparation. Statistical analysis was performed using SPSS, version 16. Data were analyzed by ANOVA and Tukey tests (α=0.05). The results showed that the active instrumentation time was significantly less in the Reciproc group (P=0.034, P<0.001). Curvature change of canal after preparation was not significantly significant. According to the results, the three files in this study prepare the canal properly and change canal curvature negligibly and are safe instruments for preparation of curved canals. Reciproc files need lesser time for preparation and can prepare the canal faster.

The present study was designed to investigate the effectiveness of mindfulness in the prevention of relapse in drug abusers. Using a quasi experimental design, 90 male drug abusers who had undergone detoxification were selected from among all detoxified individuals referred to drug rehabilitation centers in the City of Tehran. Patients were placed randomly in three groups: Mindfulness training intervention, behavioral drug reduction counseling and a control group in which no intervention was applied. Diagnosis of drug abuse was made using structured clinical interview for diagnosing axis I disorders on DSMIV (SCID-I) as well as tests to measure morphine levels in the blood. Fisher test was used to compare groups. Patients were assessed two weeks and two months after the intervention as follow up measure. Results show that both intervention groups were effective in preventing relapse as compared to the control group. Furthermore, the effectiveness of mindfulness training and BDRC was about the same. There were no significant differences between patients with and without experience of drug abuse and married and single patients. Both mindfulness training and BDRC may be considered effective practical methods in reducing the risk of relapse in male drug abusers.