27262
document
Effect of enamel preparation method on in vitro marginal microleakage of a flowable composite used as pit and fissure sealant . OBJECTIVES The aim of this in vitro study was to evaluate the microleakage in occlusal surfaces , after preparation with Er : YAG laser and compared to the diamond-bur conventional technique . METHODS Thirty premolars were divided into three groups : I - high-speed handpiece + 37 % phosphoric acid ; II - Er : YAG laser ( 350 mJ , 4 Hz and 112 J/cm ( 2 ) ) + 37 % phosphoric acid ; and III - Er : YAG laser ( 350 mJ , 4 Hz and 112 J/cm ( 2 ) ) + Er : YAG laser ( 80 mJ , 4 Hz , and 25 mJ/cm ( 2 ) ) . All cavities received the same adhesive system and were restored with flowable composite according to manufacturer 's instructions . Teeth were submitted to thermal cycling and immersed in 50 % silver nitrate solutions for 8 h in total darkness . Specimens were sectioned longitudinally in the bucco-lingual direction , in slices of 1 mm thick . Each slice was immersed into photo developing solution and was photographed , and microleakage was scored from 0 to 7 , by three calibrated examiners . RESULTS A statistically significant difference ( P < 0.0001 ) was observed between Er : YAG laser prepared and etched specimens and those in the other groups . CONCLUSIONS It can be concluded that no significant difference was noted between the two types of enamel preparation when etching was performed . Preparing and treating the enamel surface exclusively by Er : YAG laser resulted in the highest degree of leakage .
27263
Intervention_Pharmacological
enamel preparation method
27264
Intervention_Physical
Er : YAG laser
27265
Intervention_Physical
diamond-bur conventional technique
27266
Intervention_Pharmacological
high-speed handpiece
27267
Intervention_Pharmacological
37 % phosphoric acid
27268
Intervention_Pharmacological
Er : YAG laser ( 350 mJ
27269
Intervention_Pharmacological
37 % phosphoric acid
27270
Intervention_Pharmacological
Er : YAG laser
27271
Intervention_Pharmacological
Er : YAG laser ( 80 mJ , 4 Hz , and 25 mJ/cm ( 2 ) )
27272
Intervention_Physical
thermal cycling
27273
Intervention_Pharmacological
silver nitrate solutions
27274
Intervention_Pharmacological
enamel preparation
27275
Intervention_Physical
Er : YAG laser
27276
Outcome_Physical
marginal microleakage
27277
Outcome_Physical
microleakage in occlusal surfaces
27278
Outcome_Physical
microleakage
27279
Outcome_Physical
degree of leakage .
27280
Participant_Sample-size
Thirty