PURPOSE The purpose of this in vitro study was to evaluate microleakage of pit and fissure sealants after using three different pit and fissure preparation techniques: (1) traditional pumice prophylaxis and acid etching, (2) fissure enameloplasty and acid etching and (3) air abrasion and acid etching. METHODS Sixty extracted third molars with no clinical evidence of caries were randomly divid...

Multi-mode universal adhesives (UA) are indicated as either self-etch or etch-and-rinse adhesives, and manufacturers also recommend an alternative ‘selective enamel etch’ technique. Currently available laboratory data support phosphoric acid selective etching of enamel prior to use of UA to improve bond strength. In another way to improve adhesion to enamel of UA without the use of phosphoric a...

Hydrofluoric (HF)/nitric (HNO3)/acetic (CH3COOH) acid, normally referred to as the HNA method, is a widely utilized technique for performing isotropic etching on silicon (Si) in industrial Si-based processing and device construction. Here, we reported a novel etching strategy based on a HF/HNO3 process with the assistance of silver (Ag) nano-seeds, offering good controllability in preparing div...

Sacrificial etching is one of the most important process steps in micro-electro-mechanical systems technology, since it enables the generation of free-standing structures. These structures are often the main part of micro-mechanical devices, intended to sense or induce a mechanical movement. The etching process transforms an initial multi-segmented geometry and depends on material properties an...

objectives: this study aimed to compare the microleakage beneath metallic brackets following two different methods of enamel preparation and light curing. materials and methods: a total of 120 bovine deciduous lower incisors were randomly divided into four groups of 30 teeth. the preparations were as follows: group i: acid etching + transbond xt primer + direct illumination, group ii: acid etch...

Aim: To assess the influence of dental etching on the shear strength of different glass ionomer cements. Methods: The crown of 60 bovine incisors was prepared to obtain a flat, smooth surface, were attached to a PVC tube and randomly divided into six groups: Group 1 – Riva Self Cure without etching; Group II – Riva Self Cure with pre-etching; Group III – Maxxion R without etching; Group IV – Ma...

In this work, an accelerating etching method for glass named thermal electrical modified etching (TEM etching) is investigated. Based on the identification of the effect in anodic bonding, a novel method for glass structure micromachining is proposed using TEM etching. To validate the method, TEM-etched glasses are prepared and their morphology is tested, revealing the feasibility of the new me...

OBJECTIVES This in vitro study evaluated the shear bond strength (SBS) of resin composite to feldspathic porcelain after acidulated phosphate fluoride (APF) gel treatment over different periods of time. METHODS One hundred and fifty-six feldspathic specimens were divided into 12 groups. Group C received no treatment (control group). Groups APF1 through APF10, ten experimental groups, were tre...

statement of problem: hemostatic agents may affect the micro-leakage of different adhesive systems. also, chlorhexidine has shown positive effects on micro-leakage. however, their interaction effect has not been reported yet. objectives: to evaluate the effect of contamination with a hemostatic agent on micro- leakage of total- and self-etching adhesive systems and the effect of chlorhexidine a...