Soldering in Dentistry: An Updated Technical Review.

Introduction: The need to permanently join two or more pieces of metal using heat is a frequent condition in various fields of medicine such as dentistry. Welding, brazing and soldering are permanent joining techniques between different metals that require in-depth background knowledge in order to obtain predictable results.

Aim: This review examines the different methods of joining metals using heat and their fields of application.

Filter Masks during the Second Phase of SARS-CoV-2: Study on Population.

During the SARS-CoV-2 pandemic, the most common countermeasure are the use of masks, which are supposed to filter inhaled and exhaled air to reduce the spread of the virus. The masks, which are medical devices, must be used by providing appropriate instructions for correct use. This study, which examined the population during the advanced stage of the pandemic, highlighted a substantial improvement in the management and choice of masks, even though the information disseminated to the population probably should be even more detailed and precise in order to avoid incorrect behavior that could compromise the effectiveness of these devices; in fact a high percentage of subjects had behaviors that can facilitate the spread of the virus, such as the continuous attempts to correct the incorrect positioning of the mask on the face or the need to move it because it is annoying.

Alternative Methods of Sterilization in Dental Practices Against COVID-19.

SARS-CoV-2, and several other microorganisms, may be present in nasopharyngeal and salivary secretions in patients treated in dental practices, so an appropriate clinical behavior is required in order to avoid the dangerous spread of infections. COVID-19 could also be spread when patients touches a contaminated surface with infected droplets and then touch their nose, mouth, or eyes. It is time to consider a dental practice quite similar to a hospital surgery room, where particular attention should be addressed to problems related to the spreading of infections due to air and surface contamination.

Monitoring blood biomarkers to predict nivolumab effectiveness in NSCLC patients.

Background: We investigated whether early dynamic changes of circulating free (cfDNA) levels as well as the neutrophil to lymphocyte ratio (NLR) could predict nivolumab effectiveness in pretreated patients with advanced non-small cell lung cancer (NSCLC).

Methods: A total of 45 patients receiving nivolumab 3 mg/kg every 2 weeks were enrolled. Patients underwent a computed tomography scan and responses were evaluated by the response evaluation criteria in solid tumors.

Evaluation of marginal leakage after mechanical fatigue cycling of composite inlays luted with different cements.

This in vitro study evaluated the marginal microleakage of composite inlays luted with 3 different cement systems. The null hypothesis was that the luting materials would not influence dye penetration, showing the same degree of microleakage. Thirty-six sound molars were selected, mesio-occlusodistal cavities were prepared, and the teeth were randomly divided into 3 groups (n = 12).

Assessment of root canal enlargement using Mtwo and BioRace rotary files.

Objective: To evaluate root canal enlargement following mechanical shaping using 2 nickel titanium rotary systems.

Material And Methods: Forty single-rooted teeth were immersed in resin and sectioned perpendicular to the long axis at 4, 8, and 12 mm from the apex. Digital capture of sections was performed before and after canal instrumentation using Mtwo and BioRace instruments.

TEM morphological characterization of a one-step self-etching system applied clinically to human caries-affected dentin and deep sound dentin.

Purpose: To examine morphologically the hybrid layer of one-step self-etching adhesive, Clearfil S3 Bond (S3bond), in caries-affected dentin (CAD) and deep sound dentin (DSD) cavities performed clinically. For a comparative group, the two-step self etching adhesive Clearfil Protect Bond (Pbond) was used in a similar clinical situation.

Methods: This study was carried out on carious and sound teeth clinically selected for extraction.

System B, Endo-Twinn and E-Fill. True temperatures inside the canal.

Background: The aim of this study is to verify the variations of the temperature inside the root canal with three different gutta-percha heating systems.

Materials And Methods: A split-tooth model was built with a lateral groove at 3.5-mm from working length (WL) in order to insert a Chromel-Alumel K-type thermocouple placed in contact with gutta-percha.

Short-term response of three resin-based materials as desensitizing agents under oral environmental exposure.

Objective: This paper focuses on clinical responses after 7 days of oral exposure to two resin-based materials as desensitizing agents compared to a fluoride varnish and on morphological and analytical study as a means to elucidate the mechanism of action.

Materials And Methods: The elemental composition of Vertise™ Flow (VF), Universal Dentine Sealant (UDS) and Flor-Opal® Varnish (FOV) were investigated by using an X-ray energy dispersive spectrometer (EDX) in conjunction with a scanning electron microscope (SEM). SEM morphology of the material-treated dentine surfaces and pain reduction ability according to the Visual Analogue Scale (VAS) were evaluated in selected hypersensitive teeth.

Innovations in endodontic filling materials: guttapercha vs Resilon.

One of the goals of endodontic treatment is to achieve a complete, tridimensional, hermetic sealing of the root canal system to prevent the entry of microorganisms or their products through both the coronal and apical pathways. Gutta-percha is the most widely used material for root canal filling and despite its numerous properties, such as biocompatibility and thermoplasticity, it has however an important limit: the lack of adhesion to the canal walls. Attempts to address this problem have been made over the years by using endodontic cements capable of bonding to canal dentine but their tendency to resorption in time can compromise the quality of treatment.

Current dental adhesives systems. A narrative review.

Adhesive dentistry is based on the development of materials which establish an effective bond with the tooth tissues. In this context, adhesive systems have attracted considerable research interest in recent years. Successful adhesive bonding depends on the chemistry of the adhesive, on appropriate clinical handling of the material as well as on the knowledge of the morphological changes caused on dental tissue by different bonding procedures.

In vitro evaluation of the antibacterial activity of cured dentin/enamel adhesive incorporating the antimicrobial agent MDPB.

The aim of this study was to investigate in vitro the antibacterial effect of a dentin/enamel adhesive containing MDPB (Clearfil Protect Bond) after curing and to compare it with an adhesive not containing MDPB (Clearfil SE Bond). The antibacterial effect of the cured adhesives was tested on Enterococcus faecalis by the evaluation of growth inhibition in a 48-h microplate direct contact test (DCT). The presence of antibacterial activity due to soluble components was also investigated by an agar diffusion test (ADT) performed with the adhesives cured on the surface of dentin disks.

How can droplet formation occur in endodontically treated teeth during bonding procedures?

Purpose: The aim of this in vivo study was to clarify how blistering formation occurs along intraradicular dentin bonded interfaces.

Materials And Methods: Patients were selected and post space was prepared in vivo in endodontically treated teeth. Post space was etched, dried with ethanol, and bonded with one of the following adhesive systems: All Bond 2, XP-Bond, Clearfil SE Bond, Xeno III.

Ultrasound effects after post space preparation: An SEM study.

The aim of this study was to evaluate the effect of ultrasonic treatment on occlusion of dentine tubules in root canal walls after post space preparation in endodontically treated teeth. Twenty-four premolars were instrumented and filled using warm vertical condensation; after post space preparation, they were divided into two groups. The control group was treated using the etching procedure.

In vitro antibacterial activity of endodontic sealers.

Objectives: To evaluate the antibacterial activity of four endodontic sealers: one epoxy resin sealer (AH Plus), two zinc oxide eugenol (ZOE)-based sealers (Endomèthasone, Pulp Canal Sealer), and one sealer containing both ZOE and orthophenilphenol (Vcanalare).

Methods: A direct contact test (DCT) was performed. A 10 microl suspension of Enterococcus faecalis was placed on the test material 20 min, 24 h and 7 days after mixing.

Surface debris of canal walls after post space preparation in endodontically treated teeth: a scanning electron microscopic study.

Purpose: To evaluate surface cleanliness of root canal walls along post space after endodontic treatment using 2 different irrigant regimens, obturation techniques, and post space preparation for adhesive bonding.

Study Design: Forty teeth, divided into 4 groups, were instrumented, using Ni-Ti rotary files, irrigated with NaOCl or NaOCl+EDTA and obturated with cold lateral condensation (CLC) or warm vertical condensation (WVC) of gutta-percha. After post space preparation, etching, and washing procedure, canal walls were observed using a scanning electron microscope (SEM).