Evaluation and comparison of surface characteristics of commercially available TMA wires using scanning electron microscopy and optical profilometer.

AIM: The aim of this study was to evaluate and compare the surface characteristics of colored titanium molybdenum alloy archwires (purple-coated TMA and honey dew-coated TMA) and the regular titanium molybdenum alloy archwires. MATERIALS AND METHODS: The experiment comprised three groups, Group I - regular TMA archwires, Group II - purple-coated TMA archwires, Group III - honey dew-coated TMA wires involving 21 samples each. The surface characteristics were assessed using scanning electron microscopy and optical profilometer. RESULTS: The results were statistically analyzed using analysis of variance wherein Group I regular TMA wires exhibited a root mean square value of 148.071 nm and a standard deviation of 9.0027 nm followed by group II (purple-coated TMA wires) which showed a root mean square value of 84.095 nm with a standard deviation of 2.6005 nm, while group III (honey dew-coated TMA wires) was found to have a root mean square value of 71.681 nm with a standard deviation of 1.4645 nm on subjecting to optical profilometry. CONCLUSION: The surface roughness is higher for regular TMA wire exhibiting superior characteristic of color-coated TMA wires, especially honey dew-coated TMA wires over the regular and purple-coated TMA wires. This property of the archwires details regarding its application in both sliding and frictionless mechanics in retraction phase of fixed orthodontic treatment.

Evaluation of kinetic friction between regular and colored titanium molybdenum alloy archwires.

AIM: The aim of this study was to evaluate the kinetic frictional properties of colored titanium molybdenum alloy (TMA) archwires (purple-coated TMA and honey dew-coated TMA) and the regular TMA archwires. MATERIALS AND METHODS: The experiment comprised of three groups, Group I - Regular TMA archwires, Group II - Purple-coated TMA archwires, Group III - Honey dew-coated TMA wires involving 21 samples each that were evaluated for their frictional properties using Instron Universal Testing Machine. RESULTS: The results were subjected to statistical analysis using analysis of variance wherein Group I Regular TMA wires revealed mean kinetic frictional value of 8.236 N and a standard deviation of 0.4038 N, while Group II (purple-coated TMA wires) showed a mean value of 5.297 N, standard deviation of 0.3128 N and Group III (honey dew-coated TMA wires) showed a mean value of 4.206 N and a standard deviation of 0.5353 N. CONCLUSION: The kinetic frictional values are higher for regular TMA wire exhibiting superior characteristic of color-coated TMA. Wires exhibiting superior characteristics are color-coated TMA wires, especially honey dew-coated TMA wires over the regular and purple-coated TMA wires. These superior properties of newly introduced wires can be considered for its application in both details friction and frictionless mechanics in retraction phase of fixed orthodontic treatment.

Evaluation of Soft Tissue Landmark Reliability between Manual and Computerized Plotting Methods.

AIM: The aim of the study is to evaluate the reliability of soft tissue landmark identification between manual and digital plot-tings in both X and Y axes. MATERIALS AND METHODS: A total of 50 pretreatment lateral cephalograms were selected from patients who reported for orthodontic treatment. The digital images of each cephalogram were imported directly into Dolphin software for onscreen digi-talization, while for manual tracing, images were printed using a compatible X-ray printer. After the images were standardized, and 10 commonly used soft tissue landmarks were plotted on each cephalogram by six different professional observers, the values obtained were plotted in X and Y axes. Intraclass correlation coefficient was used to determine the intrarater reliability for repeated landmark plotting obtained by both the methods. RESULTS: The evaluation for reliability of soft tissue landmark plottings in both manual and digital methods after subjecting it to interclass correlation showed a good reliability, which was nearing complete homogeneity in both X and Y axes, except for Y axis of throat point in manual plotting, which showed moderate reliability as a cephalometric variable. Intraclass correlation of soft tissue nasion had a moderate reliability along X axis. Soft tissue pogonion shows moderate reliability in Y axis. Throat point exhibited moderate reliability in X axis. CONCLUSION: The interclass correlation in X and Y axes shows high reliability in both hard tissue and soft tissue except for throat point in Y axis, when plotted manually. The intraclass correlation is more consistent and highly reliable for soft tissue landmarks and the hard tissue landmark identification is also consistent. CLINICAL SIGNIFICANCE: The results obtained for manual and digital methods were almost similar, but the digital landmark plotting has an added advantage in archiving, retrieval, transmission, and can be enhanced during plotting of lateral cephalograms. Hence, the digital method of landmark plotting could be preferred for both daily use and research because of the advantages.

Clinical Utilization of M Spring for the Space Closure of Midline Diastema - Clinical Case Reports.

People approach orthodontist mainly for aesthetic purpose, midline diastema is one of the condition which causes aesthetic compromise. The midline diastema can be caused by various reasons such as high frenal attachment, midline pathology, etc. In the field of orthodontics, relapse rate is high while treating midline diastema. This relapse can be reduced only when there is bodily movement of the incisors in mesial direction. In this article, two cases of midline diastema are selected. Both the cases were treated using "M" spring which has three coils; two at periphery and one at the center and each coil was of 3mm diameter. "M" spring was fabricated using round 0.018" AJ Wilcock wire for one case and 0.017 X 0.025 TMA for another case. For both cases the duration of treatment was for six weeks. IOPA was taken after six weeks, the case in which rectangular wire was used; there was bodily movement of the central incisor in mesial direction. Whereas in round wire technique, predominantly tipping type of tooth movement was seen. The rectangular wire has two point contacts, because of which bodily movement was obtained. This technique of using rectangular wire to fabricate "M" spring has less inventory and chair side time.