تقييم أمان و أزمان نبضة مختلفة من ليزر الإريبيوم ياغ و فعاليتها في أثناء نزع الحاصرات الخزفية

Abstract EN

Background and Objective: The application of Er: YAG laser has been considered a good choice for orthodontic bracket deboning among laser-aided debonding methods.

A protocol for this application has been adopted after conducting several studies.

However, the influence of pulse duration during the removal of the ceramic brackets with the aid of Er: YAG laser has not been addressed in the previous published work.

The goal of this research is to evaluate the effect of several durations of Er: YAG laser pulses on ceramic bracket debonding.

Thus, if is to complete the appropriate parameters in the adopted protocol for effective debonding of ceramic brackets.

Materials and Methods: The sample consisted of 60 non-carious premolar teeth extracted for orthodontic purposes.

A ceramic bracket was bonded to each tooth.

The sample was divided into four groups: the first group (15 teeth) for pulse duration of 50 microseconds, the second group (15 teeth) for pulse duration of 100 microseconds, the second group (15 teeth) for pulse duration of 300 microseconds, and the fourth group (15 teeth) is a conventional bracket debonding.

All ceramic brackets in the first three groups were exposed to Er: YAG Laser for 6 seconds by laser scanning method, with the same air and water cooling conditions, pulse energy, and frequency.

The tooth temperature was monitored during the brackets debonding by a thermal camera, the ceramic brackets were removed after 18 seconds.

In the fourth group, the ceramic brackets were removed without the application of laser.

Broken brackets during the removal were counted in all samples.

Results: The results showed a statistically insignificant difference between the pulse durations of 50, 100 and 300 microsecond in terms of the temperature rise of enamel surface.

However, a statistically significant difference has been found in terms of ceramic bracket failure between the laser groups and the conventional group, with statistically insignificant difference among laser groups.

Conclusions: Within the limitations of this study, all pulses durations investigated can be used safely and effectively for ceramic bracket debonding..