Maurício Mezomo

Maxillary canine retraction with self-ligating and conventional brackets

OBJECTIVE To measure space closure during the retraction of upper permanent canines with self-ligating and conventional brackets. MATERIALS AND METHODS Fifteen patients who required maxillary canine retraction into first premolar extraction sites as part of their orthodontic treatment completed this study. In a random split-mouth design, the retraction of upper canines was performed using an elastomeric chain with 150 g of force. The evaluations were performed in dental casts (T0, initial; T1, 4 weeks; T2, 8 weeks; T3, 12 weeks). The amount of movement and the rotation of the canines as well as anchorage loss of the upper first molars were evaluated. RESULTS There was no difference between self-ligating and conventional brackets regarding the distal movement of upper canines and mesial movement of first molars (P > .05). Rotation of the upper canines was minimized with self-ligating brackets (P < .05). CONCLUSION Distal movement of the upper canines and anchorage loss of the first molars were similar with both conventional and self-ligating brackets. Rotation of the upper canines during sliding mechanics was minimized with self-ligating brackets.

Indirect bonding with thermal glue and brackets with positioning jigs.

In orthodontics the precise location of bracket placement on the teeth is a goal in order to individualize and optimize treatment outcome. The authors will describe the indirect bonding procedure with thermal glue transfer tray and brackets with positioning jigs for precise bracket placement.

TEMPERATURE RISES IN THE PULP CHAMBER WITH DIFFERENT TECHNIQUES OF ORTHODONTIC ADHESIVE REMOVAL

Introduction: The aim of this in vitro study was to compare the temperature rises in the pulp chamber and time spent with different techniques for orthodontic resin adhesive removal. Methods and Materials: Adhesive removal was performed in 20 extracted human maxillary second premolars with five techniques: high-speed tungsten carbide burs with water-cooling (BurH-cool) and without cooling (BurH), low-speed carbide burs (BurL), low-speed aluminum-oxide discs (DiscL), and low-speed fiberglass burs (BurFGL). Pulp chamber temperature was measured with a thermocouple probe and time spent was recorded with a digital stopwatch. Comparisons of temperature rise and time between the techniques were performed with Analysis of variance and Tukey’s Honestly test. Correlation between variables was investigated with Pearson’s correlation coefficient. Results: Temperature rise and time were statistically different between techniques and showed a positive correlation between them (r=0.826) (P<0.01). BurH-cool provoked the lowest temperature rise and BurFGL the highest (P<0.01). Temperature rises were higher with DiscL than with BurH and BurL (P<0.01), which showed no statistical differences between them (P>0.05). The fastest technique was BurH-cool followed by BurL, BurH, DiscL and BurFGL (P<0.01). Conclusion: BurH-cool, BurH and BurL are safe adhesive removal techniques, whereas DiscL and BurFGL may damage pulp tissues. Time spent on adhesive removal has direct effect on temperature rise in the pulp chamber.