adam

INTRODUCTION:

The purpose of this study was to compare in vitro the canal and isthmus debridement of manual-dynamic, passive ultrasonic, and laser-activated irrigation with an Er:YAG laser in mesial roots of human mandibular molars.

METHODS:

Fifty extracted mandibular molars with an isthmus were embedded in resin and sectioned axially 4 mm from the apex. The teeth were reassembled with guide pins and bolts, and the mesial canals were instrumented up to a ProTaper F2 rotary file (Dentsply Maillefer, Ballaigues, Switzerland). Teeth were randomly assigned to the following irrigant activation groups (n = 10): conventional needle irrigation (NI), manual-dynamic irrigation with a ProTaper F2 gutta-percha cone, ultrasonically activated irrigation using a size 20 Irrisafe (Satelec Acteon, Mérignac, France), and laser-activated irrigation (LAI) with an Er:YAG laser and a conical 400-μm fiber tip in the canal entrance or a 600-μm tip over the canal entrance. Root cross-sectional images were taken before and after final irrigation, and the area occupied by debris in the main canal and the isthmus was determined using image analysis software. Differences in debris before and after activation were statistically compared within and across groups.

RESULTS:

Significant reductions in debris levels were observed in all groups, except for NI and manual-dynamic irrigation (canal only). None of the methods rendered the canal systems debris free. In the canal, LAI with an Er:YAG laser and a 600-μm tip over the canal entrance removed significantly more debris than NI. In the isthmus, LAI with an Er:YAG laser and a conical 400-μm fiber tip in the canal entrance removed significantly more debris than NI.

CONCLUSIONS:

Within the limitations of this in vitro study, canal and isthmus cleanliness significantly improved after irrigant activation.

Dear Editor:

In clinical dermatology, abscesses are generally caused by secondary impetiginization of a previous furuncle or a ruptured epidermal cyst. We encountered a rare case of cutaneous abscess in the maxillo-mandibular region, complicated by bisphosphonate-related osteonecrosis of the jaw.

Since 2011, the World Health Organization has encouraged a global phase-down of the use of dental amalgam and actively supported the use of alternative, resin-based dental materials. The resins consist of (meth)acrylate monomers derived from Bisphenol A (BPA), such as Bisphenol A glycidyl methacrylate (BisGMA) and Bisphenol A ethoxylate methacrylate (BisEMA) or triethylene glycol dimethacrylate (TEGDMA) and urethane dimethacrylate (UDMA) which lack the BPA backbone. Besides monomers, other compounds such as photoinitiators and stabilizing agents can be present in the dental resin matrices. The current study consists in the development of an analytical method for the separation and identification of dental material components using LC-QTOF-MS. The developed method was applied on several dental material ingredients, unpolymerized composite resins, and a common dental sealant. The acquired high resolution accurate-mass data was analyzed using suspect screening with an in-house developed library. Next to the main components, various isomers and impurities related to the production of the main component have been detected and identified in the dental material ingredients. In total, 39 chemicals have been identified in the analyzed dental materials. On average 15 chemicals have been identified. Major components, such as BisEMA, BisGMA and TEGDMA were identified although they were not always stated in the material safety data sheets. Minor components included photoinitiators, such as ethyl 4-dimethyl aminobenzoate (EDMAB) and (meth)acrylates impurities originating from production of main ingredients.

The current paper published in Brain, Behavior, and Immunity by Kuhlman and colleagues demonstrate that even mild inflammatory responses following vaccination with the influenza vaccine are sufficient to induce depressed mood and cognitive impairments in healthy young adults (Kuhlman et al., 2018).  The authors found that following vaccination participants demonstrated changes of varying magnitude in serum IL-6 levels measured pre- and 1 day post-vaccination, and that larger increases in circulating IL-6 were associated with greater mood disturbances and cognitive symptoms.  Changes in mood and cognitive function were measured the week prior to and the week after vaccination by the analysis of daily diaries that consisted of the 15-item Profile of Mood States (POMS-15) and 3-item POMS-Confusion subscale (inability to concentrate, forgetfulness, and confusion).

Endodontic therapy aims at eliminating the existing infection and also inhibiting re-infection. Endodontic failures attribute almost 30-40% of dental failures. Microorganisms are recognized worldwide as the etiological agent for the majority of endodontic infections. The current day medicine emphasizes on understanding the etio-pathogenesis of disease process rather than just symptomatic approach. The limitations of conventional culture techniques like low sensitivity, non-specificity etc has paved way for more potential molecular biology techniques. The molecular techniques are highly sensitive & highly specific making it an integral part of modern day medicine and research. This tool gives insight to the interactions of molecules like DNA, RNA and proteins that are the key factors for life process. A significant contribution of molecular biology methods to medical microbiology relates to the identification of previously unknown human pathogens. More than 50 % of previously uncultivable oral bacteria have been identified by this advanced technique. The techniques can be applied extensively for diagnosis, management and prevention of pathology. This review intends to familiarize various molecular techniques and underlying concepts. This in turn facilitates in implementing them to various contemporary areas of research.