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Evaluation of the Curing of Adhesive Systems by Rheological and Thermal Testing
Published on: July 3, 2020
Comparative study of excess glue around metallic APC™ Flash-Free adhesive system
Roula Akl1, Joseph Ghoubril1, Geneviève Zgheib1
1Département d’Orthodontie, Faculté de Médecine Dentaire, Université Saint-Joseph, 650 rue de Damas, B.P. 11-5076 Riad El Solh, Beyrouth, Liban
Introduction:
The aim of this in vitro study was to determine if there is a significant difference in the excess adhesive flash between the metallic APC™ Flash-Free adhesive system, the APC™ pre-coated adhesive system and a conventional uncoated system.
Materials And Methods:
One hundred eighty-six freshly extracted human premolars were randomly and blindly divided into three groups according to the type of brackets. Group A (control group n=60): The conventional uncoated metallic bracket (Victory, 3M Unitek®) with a Transbond XT™ Light Cure Adhesive Paste was used. Group B (n=60): The APC™ II metallic maxillary precoated premolar brackets was used. Group C (n=66) : The metallic APC™ Flash-Free adhesive system without flash clean up was used. Images were taken at 40 magnifications in a dental microscope (Leica M320 for dental, Wetzlar, Germany) then analyzed with the ImageJ software and the area of excess adhesive flash was measured.
Results:
The mean percentage was significantly different between the three groups (p<0.001; ANOVA). It was significantly smaller for brackets in the APC Flash-Free group (p<0.001), and the difference was not significant between conventional brackets and APC (p=0.224).
Discussion:
The new technique seems to reduce the amount of excessive adhesive around orthodontic brackets.

