CATALINA IULIA SAVEANU, OANA DRAGOS, VLAD DANILA, CORINA CHEPTEA ULTRASTRUCTURAL ANALYSIS BY SCANNING ELECTRON MICROSCOPY OF DENTAL STRUCTURES CONDITIONING WITH ORTOPHOSPHORIC ACID AND ER.CR: YSGG LASER IRRADIATION This study evaluated the ultra-morphological effects of ortophosforic acid and Er.Cr: YSGGLASER on human dentin by means of a field emission in-lens scanning electron microscope. The study was conducted in vitro on human teeth extracted for orthodontic or periodontal reasons, after obtaining informed consent of patients. The samples were sectioned mesial-distal in the longitudinal direction (diamond discs) finished 400, 600, 1200 and 2400 grit SiC paper, polished with gums and abrasive paste 6, 3, 1 and 0,25 mm under continuous irrigation. The samples were divided in five groups depending on the type of conditioning as follows: GR.1= 5 s; GR.2= 10 s; GR.3= 15 s; GR.4= 20 s; GR.5= Er,Cr: YSGGlaser irradiating at 30% water and 60% air at 3W/15 Hz. The materials used for conditioning the teeth were SE™35% (Scotchbond™ Etchant Phosphoric Acid -3M ESPE-Seefeld, Germany) and MG6-MZ6 tipswith Er, Cr: YSGGlaser (Biolase Waterlase-MD), according to manufacturer’s instructions. The specimens were prepared for observation under SEM with ×1,000 and ×4,000 magnifications. The acid type, concentration and time of action determines dentin demineralization and modifying or removing smear layer. Er.Cr: YSGG laser treatment of non-carious dentin, a laser power of 3 W is found to be the optimal to improve the micromorphology of dentin.
Keywords: scanning electron microscopy, Er, Cr: YSGGlaser, phosphoric acid, dentin, ultra-structure, collagen fibriles