The Observation Of Different Polishing Methods Upon Teeth Surface By Scanning Electron Microscopy After The Treatment Of Ultrasonic Scaling

[Objective]Effectively removing plaque and calculus is an essential measure to the treatment of periodontal disease, which also plays a key role in the prevention of periodontal diease. Ultrasonic scaling is one of the most fundamental treatments of it. But there are some shortcomings of this treatment such as causing scratchs and the rough of the surface of the enamel, thereby resulting in rapid plaque and calculus deposition, consequently the self-cleaning of the teeth impaired. As a result, additional polishing becomes inevitable. There are two polishing methods employed in clinic currently: rubber cups polishing and sandblasting polishing. There still remains controversy about what effectiveness of two polishing methods are and whether it is necessary to polish with rubber cups dipping polishing paste after ultrasonic scaling +sandblasting. People hold on different ideas about it; someone finds out the surface of the enamel becomes smoother after scaling + sandblast-ing, combined with the form of the enamel rod and small circular arch of the enamel rully increasingly identifiable, there are no scratch on the surface of the enamel. While others insist: it's true that the surface of the teeth become smoother while many shallow scratch can be detected after the treatment, most of which are small point assembled irregularly, consquently, imported fine particles polishing paste or silicone particles should be applied to the teeth with a intention to improve teeth smoothness after treatment.But whether it is necessary to use rubber cups dipping polishing paste to polish after sandblasting still remains controversy: someone believes although the surface of the teeth is smoother and delicate after sandblasting, and there is no damage to the structure of the teeth, still, there are minor worn can be detected after polishing. Others hold that the surface of the teeth become rougher than before after sandblasting, but it can be smoothed further after polishing with polishing paste.We made a comparison of the effectiveness of the two polishing methods, with a intention to confirm whether it is necessary to polish the surface of teeth with rubber cups dipping polishing paste after ultrasonic scaling +sandblasting and sandblasting alone and to offer reference for clinical therapy.[Material and methods]42 extracted teeth from orthodontic patient needed were randomly divided into seven groups with 6 teeth each, control group; ultrasonicscaling group; ultrasonic scaling + polished group; ultrasonic scaling + sandblasting group; ultrasonic scaling + sandblasting + polished group; sandblasting group; sandblasting + polished group. After different treatments , cleanness of the teeth and defection of the surface as well as its depth were scaned by electron microscope ,the roughness of enamel were tested by profilometer, the data were analyzed for ANOVA & LSD-t test by SPSS 15.0.[Results]The teeth from control group were clean, flat under naked eye-observation,and the enamel was flat with a distinctive pattern of enamel rod as well as small circular arch under the observation of electron microscope, there were no scratch on the surface of the enamel can be seen.The teeth of ultrasonic scaling group was clean, rough under naked eye-observation and the surface of the enamel seems like rugged peaks which was unflat with deeper scratch on the surface of the enamel when observed with electron microscope. Normal enamel surface structure was invisible.The teeth from ultrasonic scaling + polished group,ultrasonic scaling + sandblasting group , ultrasonic scaling+ sandblasting + polished groups were observed with naked eyes as well as electron microscope either, there were no significant differences to be detected on the surface of the teeth,which means the surface is clean, depth of scratch became shallow, some small spots defection could be seen.The teeth of sandblasting group , sandblasting + polished group were observed in the same way as above only found out the surface of teeth was clean, flat and the pattern of enamel rod and small circular arch rully visible, there were no scratch on the surface of the enamel.LSD-t test show the significant differences between the control group and ultrasonic scaling group(p<0.05), no significant differences between the control group and the other groups; the significant differences between the ultrasonic scaling group and the other groups(p<0.05) ; no significant differences between the groups within ultrasonic scaling + polished group, ultrasonic scaling + sandblasting group,ultrasonic scaling+ sandblasting + polished group(P>0.05); no significant differences between the sandblasting group and sandblasting + polished group(P>0.05).[Conclusion]1. Polishing is needed after ultrasonic scaling of the teeth.2.There are no statistical significance differences between groups with ultrasonic scaling + polished group and ultrasonic scaling + sandblasting treatment, the effectiveness of the two polishing methods is same.3. It is no longer needed that of polishing with rubber cup dipping polishing paste after ultrasonic scaling + sandblasting.4.There are no statistical significance differences between groups withsandblasting group and sandblasting + polished treatment, it is no longer needed that of polishing with rubber cup dipping polishing paste after sandblasting alone.