Prof. Angela Harris

Permanent URI for this collection

https://hdl.handle.net/10566/1895

Prof. Angela Harris

Position: Head of Orthodontics
Department: Orthodontics & Paediatric Dentistry
Faculty: Dentistry
Qualifications: PhD FCD(SA) Orthodontics, MChD, Hons BSc (Epidemiology), BChD, Dipl Tertiary Education
My publications in this repository
More about me: here, and here
Tel: 021 937 3105
Fax: 021 931 2287
E-mail: ampharris@uwc.ac.za

Browse

Browsing by Author "Grobler, Sias Renier"

Now showing 1 - 1 of 1
  • Thumbnail Image
    Item
    Orthodontic molar brackets: the effect of three different base designs on shear bond strength
    (Master Publishing Group, 2011) Hudson, Athol; Grobler, Sias Renier; Harris, Angela
    The purpose of the study was to assess the relative base designs of three different maxillary molar stainless steel brackets with reference to the shear bond strength of three different adhesive resins. The molar brackets used were Victory series (3M Unitek), Upper Molar (GAC) and Optimesh XRT (Ormco). The adhesives used were Transbond XT (3M Unitek), Enlight (Ormco) and Sure Ortho Light Bond (Sure Orthodontics). The human enamel specimens (144) were randomly divided into nine groups and each group (n=16) was allocated to a bracket/adhesive combination. The contact surface of each of the bracket bases was measured three dimensionally using a reflex microscope. The base designs were also subjected to further microscopic investigations. The brackets were bonded to the enamel, temperature cycled and the shear bond strength was measured. The size and design of each of the brackets was different. The base size, surface treatment, mesh strand diameter and aperture size of the bracket base mesh have a significant effect on the shear bond strength at the bracket/adhesive interface. The shear bond strengths of all three Ormco bracket/adhesive resin combinations (5.8-6.8 MPa) were significantly lower (p<0.05; Kruskal-Wallis) than the other six bracket/adhesive combinations (9.4-12.1 MPa). The different adhesive types (3 types) could not be mainly responsible for the low shear bond values found for the Ormco bracket. The 3M Unitek combination of the Victory series bracket and Transbond XT adhesive proved to have a high shear bond strength without enamel damage.