ABSTRACT
OBJECTIVE: The purpose of this study was to evaluate the surface roughness (SR) of 2 types of orthodontic archwires made by 4 different manufacturers. METHODS: This in vitro experimental study was conducted on 35 specimens of 7 different orthodontic archwires, namely, 1 nickel-titanium (NiTi) archwire each from the manufacturers American Orthodontics, OrthoTechnology, All-Star Orthodontics, and Smart Technology, and 1 stainless steel (SS) archwire each from the manufacturers American Orthodontics, OrthoTechnology, and All-Star Orthodontics. After analyzing the composition of each wire by energy-dispersive X-ray analysis, the SR of each wire was determined by scanning electron microscopy (SEM) and surface profilometry. Data were analyzed using the Kruskal-Wallis and Mann-Whitney U tests (alpha < 0.05). RESULTS: The average SR of NiTi wires manufactured by Smart Technology, American Orthodontics, OrthoTechnology, and All-Star Orthodontics were 1,289 +/- 915 Adegrees, 1,378 +/- 372 Adegrees, 2,444 +/- 369 Adegrees, and 5,242 +/- 2,832 Adegrees, respectively. The average SR of SS wires manufactured by All-Star Orthodontics, OrthoTechnology, and American Orthodontics were 710 +/- 210 Adegrees, 1,831 +/- 1,156 Adegrees, and 4,018 +/- 2,214 Adegrees, respectively. Similar to the results of profilometry, the SEM images showed more defects and cracks on the SS wire made by American Orthodontics and the NiTi wire made by All-Star Orthodontics than others. CONCLUSIONS: The NiTi wire manufactured by All-Star Orthodontics and the SS wire made by American Orthodontics were the roughest wires.
Subject(s)
Microscopy, Electron, Scanning , Orthodontics , Stainless SteelABSTRACT
The main goal of this research was to evaluate the sagittal and vertical effects of Hyrax [tooth born] and Haas [tooth-tissue born] rapid palatal expanders on dentoskeletal structures of patients with maxillary constriction characterized by bilateral posterior cross bite. A nonrondomized clinical trail of 22 patients 12 to 14 years old [mean age 12.5 years] with maxillary constriction who were divided into two groups, was undertaken. Group-l consisted of 11 patients who received treatment by Hyrax type rapid palatal expander [RPE]. Group- II composed of 11 patients who received treatment by Haas RPE. Two lateral cephalograms were taken, one before and the other after the palatal cusps of the upper posterior teeth reached the buccal cusps of lower posteriors consequent to expansion. The activation period lasted from 12-16 days with a mean value of 13.5 days. On each lateral cephalogram 8 linear and 10 angular parameters were measured, recorded and compared to a nearest of 0.5 mm and 0.5 degree respectively. Statistical analyses were performed using Kolomogrovsmirnov and paired t-test. A student t-test was used for comparison of two group. In both groups significant increases in lower anterior facial height were observed. The value [ANS-ME] was increased 1.30mm in Hyrax [P=0.009] and 1.80mm in Haas group [P=0.032].Statistically neither of the appliances showed a significant effects on sagital position of the maxilla. The mandible was rotated downward and backwards. SNB angle decreases 0.65 and 0.43 degrees in Hyrax and Haas group respectively. ANB angle was increased by means of 0.60 degree [p= 0.030] in Hyrax and 0.53 degree [p=0.08] in Haas group.The maxilla kept its position sagitally, pre to post treatments, but showed inferior displacement in both groups. The mandible displayed a tendency to rotate downward and backward in both groups.Upper anteriors tipped palatally