|Baltic Dental and Maxillofacial Journal|
June, 2009, Vol. 11, No. 2
Stress distribution of an internal connection implant prostheses set: A 3D finite element analysis
Intra-articular injection of hyaluronic acid for temporomandibular joint osteoarthritis in elderly patients
Evaluation of tensile strength of different configurations of orthodontic retraction loops for obtaining
© 2009 Stomatologija
Stomatologija 2009; 11 (2): 66-69 239 KB
Evaluation of tensile strength of different configurations of orthodontic retraction loops for obtaining optimized forces
Miceli Beck Guimaraes Blaya, Graziela Henriques Westphalen, Magali Beck Guimaraes, Luciana Mayumi Hirakata
The aim of this study was to analyze the mechanical behavior of different orthodontic retraction loops. Two designs of orthodontic loops for closing space were analyzed: teardrop-shaped (T) and circle-shaped loop (C), of two different heights (6 and 8 mm), and two types of orthodontic wires (stainless steel 0.19’ × 0.25’; TMA titanium molybdenum alloy 0.016’ × 0.016’). The sample consisted of 80 loops, divided into 8 groups determined by the combination shape/height/type of wire, which were submitted to tensile testing at a speed of 2 mm/min., to measure the quantity of force generated when activated in the interval of 0.75 mm and 2.25 mm. The results were submitted to the ANOVA and Tukey statistical tests to compare the groups, and the Student’s-t test to compare the means of two groups. Statistically higher values were observed for the size 6 mm, circle shape and stainless steel composition. The group “teardrop-8 mm-TMA” together with the group “circle-8 mm-TMA” presented the lowest mean value, differing statistically from all of the other groups. It was concluded that the alloy of the wire and the height of the loop would be more important than the loop design.
Key words: orthodontics, orthodontic loop, retraction.
Received: 14 10 2008
Accepted for publishing: 19 06 2009
*Pontifical Catholic University of Rio Grande do Sul, Brazil
Miceli Beck Guimaraes Blaya* D.D.S, PhD Student
Graziela Henriques Westphalen* D.D.S, M.S., PhD Student
Magali Beck Guimaraes* D.D.S, M.S. Student
Luciana Mayumi Hirakata* D.D.S, M.S., PhD, Dental Material Professor.
Address correspondence to Dr. Luciana Mayumi Hirakata, Av. Ipiranga, 6681 - Building 6, Porto Alegre Rio Grande do Sul, Brazil, Zip code: 90619-900.