Aim: to compare the effect of multiple usage and surface coarseness of diamond
burs on marginal microleakage of cervical resin composite restorations.
Materials and methods: sixty extracted premolars without caries were chosen. The
sample was rand
omly divided into three groups: n1=n2=n3=20. Group(1): class v cavities
were prepared using super coarse diamond burs, group(2): prepared by coarse diamond
burs, whereas group)3(: prepared by medium coarse diamond burs. All cavities were
restored by resin composite, then The teeth were thermocycled and immersedIn5%solution
of methylene blue dye for 12hours.Then the teeth were sectioned vertically, Dye
penetration was evaluated using a 10X stereomicroscope at the occlusal and gingival
margins. Data were collected and statistical analysis was conducted.
Results: The results showed that the multiple use of super coarse diamond burs
caused no significantly statistically affect on occlusal and gingival microleakage (P>0.05).
However, the multiple use of coarse and medium diamond burs caused significantly
statistically affect on gingival marginal microleakage (P<0.05).
