different techniques have been introduced for the removal of ceramic brackets. since the early 1990s, lasers have been used experimentally for debonding ceramic brackets. the goal of this study is to give a comprehensive literature review on laser-aided ceramic bracket debonding. pubmed and google scholar databases were used to identify dental articles with the following combination of key word...

BACKGROUND AND OBJECTIVES The purpose of this in vitro study was to evaluate the bond strength of the laser-etched base bracket, site of bond failure, and evaluate for enamel remnants on the bracket base after debonding, when compared to foil mesh base bracket. MATERIALS AND METHODS Sixty noncarious, human premolar extracted for the orthodontic treatment were used for this study. The teeth we...

Orthodontic torque expression is the result of axial rotation of rectangular archwires within a rectangular bracket slot. This study investigates the effect of bracket material on torque expression. Torque exerted by a rotating archwire on each bracket will be measured as well as the relative deformation of each bracket slot. A total of 60 tests were performed where archwires were rotated withi...

Objectives: The study aimed to investigate the effect of direction light curing on bond strength and adhesive polymerization orthodontic metal brackets. Material Methods: In this in vitro investigation, 75 extracted human upper premolars were randomly divided into three groups according direction: Group A (20 s from occlusal side bracket), B (10 10 gingival), C (5 four corners bracket). After b...

OBJECTIVE The purpose of this study was to evaluate the effects of three different surface conditioning methods on the shear bond strength (SBS) of metal brackets bonded directly to gold alloy with chemically cured resin. METHODS Two hundred ten type III gold alloy specimens were randomly divided into six groups according to the combination of three different surface conditioning methods (alu...

Kishino's knot is not detected by the fundamental group or the bracket polynomial; these invariants cannot differentiate between Kishino's knot and the unknot. However, we can show that Kishino's knot is not equivalent to unknot by applying either the 3-strand bracket polynomial or the surface bracket polynomial. In this paper, we construct two non-trivial virtual knot diagrams, K D and K m , t...

Objective: To evaluate the shear bond strength of lingual orthodontic brackets with resin or metal pads, the location of bond failure and the adhesive remnant index (ARI). Methods: A total of 40 extracted upper premolars were randomly divided into two groups of 20 each: bonding with brackets having (1) pads with extended resin directly on the lingual surface of teeth, and (2) pads with metal...

Various aspects of the Nahm equations in 3 and 7 dimensions are investigated. The residues of the variables at simple poles in the 7dimensional case form an algebra. A large class of matrix representations of this algebra is constructed. The large N limit of these equations is taken by replacing the commutators by Moyal Brackets, and a set of non trivial solutions in a generalised form of Wigne...

A supersymmetric Lorentz invariant mechanism for superspace deformations is proposed. It is based on an extension of superspace by one λ a or several Majorana spinors associated with the Penrose twistor picture. Some examples of Lorentz invariant su-persymmetric Poisson and Moyal brackets are constructed and the correspondence: θ mn ↔ iψ m ψ n , C ab ↔ λ a λ b , Ψ a m ↔ ψ m λ a mapping the brac...