Research Project Submitted to the Faculty of Oral and Dental Medicine Cairo University

Abstract

This is an in vitro study to evaluate and to compare the frictional force between 0.018" & 0.022" stainless steel, titanium, and glass re-inforced composite brackets with three types of archwire alloys. A total of 144 brackets and archwire specimens were used. A simulating canine retraction system was constructed to measure the frictional force between archwire I bracket combination using universal testing machine (Lloyd Instrument.) • under dry state. A new bracket wire combination was used for each test and each process was repeated six times.

B-titanium archwire had significantly highest frictional force than stainless steel archwire in each 0.018" and 0.022" brackets type except 0.018" stainless steel bracket and 0.022" glass re-inforced composite

.• bracket B-titanium archwire reveal• no significant difference in frictional force in comparison with all archwire alloys tested

0.016" x 0.022" stainless steel archwire produced higher frictional force in 0.018" slot glass re-inforced composite bracketthan 0.018" slot stainless steel and titanium brackets. Additionally 0.017" x

0.025" nickel titanium archwire produced higher frictional force in

0.018" slot titanium brackets than glass reinforced composite brackets.

The frictional forces in all 0.022" brackets type were comparable regardless of bracket material. There is no significant difference in frictional force of all 0.022" brackets with all archwire alloys tested. . Additionally there is no significant difference in frictional force between 0.018" stainless steel and titanium bracket with all archwire alloys tested.