Publications by authors named "Thomas Gerard Bradley"

Introduction: The purpose of this study was to compare galvanic currents generated by different combinations of commonly used brackets and archwires.

Methods: As-received stainless steel, nickel-titanium, and beta-titanium wires were coupled to stainless steel and titanium brackets in an artificial saliva medium. The galvanic current and amount of charge transferred for each pair were monitored with a zero resistance ammeter for 10 hours.

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Objective: To evaluate and compare the shear bond strengths of two adhesives using two types of brackets: a conventional and a self-ligating bracket system.

Materials And Methods: Sixty extracted human premolars were collected. The premolars were randomly divided into three groups of 20 teeth.

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Objective: To compare as-received copper-nickel-titanium (CuNiTi) archwires to those used in patients by means of differential scanning calorimetry (DSC). Also, the thermal or phase properties of 27 degrees C, 35 degrees C, and 40 degrees C CuNiTi archwires were studied to ascertain if their properties match those indicated by the manufacturer.

Materials And Methods: Six wires of 27 degrees C, 35 degrees C, and 40 degrees C CuNiTi were tested as-received, and six each of the 27 degrees C and 35 degrees C wires were examined after use in patients for an average of approximately 9 and 7 weeks, respectively.

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Thermocycling simulates the temperature dynamics in the oral environment. With direct bonding, thermocycling reduces the bond strength of orthodontic adhesives to tooth structure. The purpose of this study was to evaluate the shear bond strengths (SBS) of one direct and two indirect bonding methods/adhesives after thermocycling.

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The purpose of this study was to evaluate and compare the shear bond strength and the sites of bond failure for brackets bonded to teeth, using two indirect-bonding material protocols and a direct-bonding technique. Sixty extracted human premolars were collected and randomly divided into three groups. The direct-bonded group (group 1) used a light-cured adhesive and primer (Transbond XT).

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The purpose of this study was to evaluate the alteration in surface characteristics after orthodontic debonding of two types of porcelain systems commonly used in prosthetic dentistry. For this purpose, porcelain specimens were fabricated from low-fusing (n = 20) and high-fusing (n = 20) porcelain. The baseline surface roughness, color, and gloss were evaluated using profilometry, color shade index, and gloss study.

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