There are various methods and devices developed to remove separated instruments. However, each method and each device varies in separated file removal time and dentin sacrifice. None of them has been perfect for predictable outcomes due to the limitations of the usage. A novel file removal system was developed to maximize the success in separated file removal and minimize the iatrogenic events. This article illuminates the technique to remove a separated instrument with the newly developed system. Three difficult-looking cases were presented here for separated file removal and all of the three separated files were retrieved with the new technique, which would not have been possible if it had not been for the new file removal system. The postoperative radiographs in comparison with the preoperative radiographs show the minimum dentin sacrifice and safe removal in all the three cases. All the separated instruments were retrieved within 6 minutes, indicating the technique applied to those cases was efficient with predictable outcomes.

Traditionally, endodontic treatment on mandibular incisors is regarded as rather simple, thus it is widely considered that a less-than-experienced clinicians can perform the treatment satisfactorily. However, it has been evidenced that surprisingly more than 40% of the mandibular incisors have two canals; hence its treatment may not be as easy as widely considered.

The purpose of this article is to illustrate how complicated the mandibular incisors canal anatomy can be, and suggest several clinical implications on its treatment.

In response to patient requests, aesthetic restoration has succeeded metal restoration as the mainstream method of treating proximal cavity of the molar region. This method has been used in composite resin filling, ceramic inlay, composite resin inlay and other modes, but fine filling has been difficult to achieve in direct filling with composite resins using the naked eye. Here, we report the achievement of good 45 and 46 restorations using the rubber wedge method under microscopic observation for sound treatment.

Extensive surgical flaps in implant surgery were introduced by Branemark in 1970 to expose the underlying bone for better visualization of the surgical field. Over the past four decades, the flap design has undergone several modifications. Although flap reflection in the surgical field may reduce the risk of bone fenestrations and dehiscences, it is also associated with some degree of morbidity and discomfort and requires suturing to close the surgical wound. Recently, the concept of flapless implant surgery has been introduced in order to preserve the vascular supply and existing soft tissue contours with less morbidity. The flapless implant surgery is considered to be a blind technique with many limitations, such as inability to assess the implant site because there is no direct visualization of the bone, the inability to preserve keratinized mucosa, inability to prevent resorption of the facial crestal bone, inability to perform immediate loading, lack of proper drilling depth assessment, and inability to correct peri-implant defects as they are not exposed during surgery. However, despite these drawbacks, the flapless technique also has several potential advantages, including the reduction of morbidity, increased patient comfort, reduction of intraoperative bleeding, reduction of surgical time and minimal disruption of blood supply to the site. The aim of this study was to evaluate the efficacy of microscope-supported flapless surgery for dental implants.

Introduction: The goal of the present study was to improve the poor handling of calcium silicate cement (CSC) and to develop materials that can be used as root canal sealing materials by adding a radiopacity agent (RA), Bi₂O₃ or Ta₂O₅, and/or an anti-washout admixture (methylcellulose, MC) with different molecular weight of MC (MC4000, 400, 25). We examined the radiopacity, flow, and setting time according to ISO 6876-2012.

Methods: Samples for the radiopacity test were prepared by adding RA to Portland cement (PC) up to final concentrations (%) of 0, 5, 10, 15, 20, and 25, respectively. Samples for the flow and setting time tests were prepared using mineral trioxide aggregate as a control group. In test groups, final concentrations of 18% RA and 2% MC, or 20% RA alone were added to PC. All of the methods in the present study conform to ISO 6876-2012.

Results: A radiopacity test revealed that the radiopacity of PC containing over 10% volume of each RA was higher than or equal to standard radiopacity. PC containing Ta2O5 and the MC25 group passed a flow and setting time test.

Conclusions: Bi₂O₃ and Ta₂O₅ can be used similarly in radiopacity, flow value and setting time test. The flow and setting time of CSC varied significantly with the molecular weight of the added MC.

Metaplasia is a reversible change in which one adult cell type is replaced by another adult cell type, and this phenomenon is usually associated with inflammation and neoplasms. Although metaplasia is also observed in the dental pulp consisting of cementum-like and/or osteoid tissues, it is rarely observed in human dental pulp tissues. We evaluated the histopathological characteristics of cemental metaplasia in the non-treated human dental pulp tissues of surgical specimens to treat squamous cell carcinoma or ameloblastoma. The histopathological study revealed cementum-like tissues with embedded cells, a lamellar structure, and Sharpey’s fiber-like features adjacent to the dentin in the dental pulp, showing cemental hyperplasia of the root and/or root resorption by progression of ameloblastoma. The metaplastic cementum-like tissue was mixed with dystrophic calcification in some areas. These findings suggest that the presence of cemental metaplasia and dystrophic calcification in the dental pulp should be considered in endodontic clinics. In addition, these structures might be associated with chronic stimuli and/or aging.