[Microscopic comparison of the miniscrew's surface used in orthodontics: before and after use].
BACKGROUND
The aim of our work is to study the modifications affecting the surface condition of miniscrews retrieved from patients following an orthodontic treatment and comparing these miniscrews to unused ones.


METHODS
This study involved ten miniscrews placed in seven patients after orthodontic treatment for various indications. These miniscrews of the same manufacturer (Dual Top Anchor System® [Jeil Medical Corporation, Seoul, Korea]) were observed under optical microscope (Leica DM2500M) in order to examine their surface. Four new Miniscrews of different manufacturers, including the manufacturer of Miniscrews trademarks patients (Abso Anchor [Dentos, Daegu, South Korea] Infiniti [DB Orthodontics, Silsden, West Yorkshire, UK], Dual Top(®) [Jeil Medical Corporation, Seoul, Korea], IMTEC(®) [Ardmore, Okla]) were examined under the same microscope to compare with the used miniscrews.


RESULTS
The study of the new miniscrews showed an irregular surface with machining and polishing defects, in the form of stripes that could constitute election's point for electrochemical attacks. Compared with the new one, the miniscrew used showed pitting corrosion attacks and cracks, mainly in the machining defects. These attacks were localized over the whole of miniscrews.


CONCLUSIONS
It is suggested that improving the surface finish can increase the corrosion resistance of these miniscrews.
Département d'Orthopédie Dentofaciale, Faculté de Médecine Dentaire, Université Hassan II Ain Chok, Casablanca, Maroc. mouradsebbar@hotmail.com
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M
Sebbar
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Bourzgui
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Lazrak
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B
Aazzab
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El Quars
D001863:Bone Screws; D003343:Corrosion; D003799:Dental Stress Analysis / Q000379:methods; D019544:Equipment Failure Analysis / Q000379:methods; D006801:Humans; D008853:Microscopy; D009018:Morocco; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation; D016382:Orthodontic Appliance Design; D009970:Orthodontics / Q000295:instrumentation* / Q000379:methods; D013499:Surface Properties