Assessment of Superficial Rugosity of Cast Titanium in Fluoride Solutions and Artificial Salive

Cylindrical specimen (20 mm x 5 mm, n = 5) consisting of commercially pure titanium ASTM/grade 2 (Ti2 – Dentaurum J.P. Winkelstroeter KGPforzheim, Germany) were casted in the Rematitan system (Rematitan, Dentaurum J.P. Winkerstroeter KG, Pforzheim, Germany) by Vaiazzi Dental Laboratory (São Paulo SP, Brazil). All specimens were cold mounted with epoxy resin and then received the standard metallography procedure for titanium. The specimens were mechanically polished on wet SiC paper grade 1001000 (Strues, Denmark), and on successively finer grades of diamond paste 6, 3 and 1 μm (Strues, Denmark). Exposed surface areas of the specimens were 90 to 100 mm. They were then degreased in ethanol and rinsed with distilled water. The polished surfaces were examined by optical microscopy (BX600, Olympus) before fluoride attack. All test solutions were prepared by Mil Fórmulas pharmacy (Rio de Janeiro RJ, Brazil). The specimens (n = 5) were divided into 5 groups (one for each group) of different tested solutions: Group 1) synthetic saliva with pH 7.0 (control); Group 2) 1.23% acidulated phosphate fluoride (APF) gel with pH 3.5; Group 3) 2% NaF gel with pH 6.5; Group 4) 0.05% NaF solution with pH 4.0; and Group 5) 0.05% NaF solution with pH 7.5. The specimens were exposed to these solutions for 16 minutes. To simulate an intra oral condition, after attack the specimens were immersed in synthetic saliva waved for 96 hours in magnetic stirrer. The composition of