Elastomerik ölçü maddelerinin detay kopyalama özelliklerinin incelenmesi

The aim of this study was to evaluate the detail reproduction of dentin surfaces with hydrophobic and hydrophilic elastomeric impression materials and their ability to transfer the details onto models produced from such impressions.In this study, Garant L DuoSoft (IGL) with polyether structure, three different brands of polyvinylsiloxane (PVS) [Panasil ?nitial Contact Light (PIC), Panasil Contact Plus (PC) & PCNS having the same chemical structure as Panasil Contact Plus but excluding surfactant], three brands of Type IV gypsum model materials including Prostone 21, Fujirock, Duralit S) and polyurethane resin based model material (Alpha Die Top) were examined for surface roughness.Wettability properties of impression materials were determined during and after setting by contact angle measurement with sessile drop technique. Deionized water at a quantity of 4 ?l was used as test liquid. The contact angle measurements have been recorded on second basis during an evolution period of 135 seconds. For the detailed evaluation of reproduction 0.7-0.8 mm dentine segments were used as reference surfaces. In accordance with the examination methods, dentin surface preparation was made with 12 fluted tungsten carbide finishing bur [SEM (scanning electron microscopy), optic profilometer] or SiC paper, grit no.180-1200 [Atomic force microscopy (AFM)]. Moisture formation on dentin surfaces was provided via pulpal pressure simulation. Specimens (10 dentin specimens, 10 impression specimens for each of impression material from dry and wet dentin surfaces as well as 10 polyurethane resin specimens for each group) were analyzed with 3 dimensional optic profilometer. One specimen from each group was analyzed with SEM and AFM. Model specimens produced from Type IV reinforced gypsum were analyzed using optic profilometer and SEM. Objective analysis were performed by using average roughness value (Ra) with 3 dimensional optic profilometer.Contact-angle values were analyzed using 2-way analysis of variance (p<0,001) and Tukey HSD tests (p<0,05). Detail reproduction was tested with three wayviiianalyses of variance (p<0,05). Bonferroni correction, Tukey HSD tests (p<0,0125), Student?s t test with Bonferroni correction (p<0,0625) were used.During setting, initial contact angle values were measured as 67,5 ± 3,25º (IGL), 71,3 ± 10,7º (PIC), 74,3 ± 3,28º (PC), 88,1 ± 4,42º (PCNS), respectively. The contact angle values at 135th second were 14,6 ± 2,67º (IGL), 0 ± 0º (PIC), 58,7 ± 2,27º (PC), 78,3 ± 4,73º (PCNS). Contact angle measurements resulted in significant differences for the impression material used and time course of the measurement (p<0,001).After setting, initial contact angle values were measured as 64,4 ± 8,88º (IGL), 52,2 ± 2,47º (PIC), 103,4 ± 2,23º (PC) and 110,7 ± 0,73º (PCNS) respectively. The contact angle values at 135th second were 40,8 ± 1,96º (IGL), 40,8 ± 1,96º (PIC), 40,8 ± 1,96º (PC) and 110,1 ± 0,76º (PCNS). Contact angle measurements resulted in significant differences for the impression material used and time course of the measurement (p<0,001).Mean Ra value of dentin surfaces was 0,39 ± 0,12 ?m. Ra values of impression materials (0,48 ± 0,10 ?m for IGL, 0,36 ± 0,06 ?m for PIC, 0,32 ± 0,08 ?m for PC and PCNS 0,54 ± 0,23 ?m for PCNS) prepared from dry dentin surfaces were not different from dentin surfaces (p>0,0125). With regard to subjective and objective evaluation, Ra values of impression materials produced from moist dentin surfaces, (0,41 ± 0,06 ?m for IGL, 0,36 ± 0,08 ?m for PIC and 0,34 ± 0,06 ?m for PC) were not significantly different (p>0,0125). Hydrophobic PCNS impression material showed similar detail reproduction ability in dry field whereas detail looses with regard to subjective evaluation and increased roughness values (Ra=0,68 ± 0,35 ?m) with regard to objective evaluations were recorded (p=0,004).Polyurethane based model material successfully copied the surface texture produced by tungsten carbide bur (p>0,0625). However, Type IV gypsum material was unable to copy this texture to the same extent.Keywords: roughness, contact angle, pulpal pressure, moisture, polyurethane resin