Effect of Prophylactic Pastes on Surface Gloss of Ceramics
Objectives: To evaluate the effect of prophylactic pastes on the surface gloss of two commonly used ceramic materials and human enamel. Methods: A total of forty specimens, composed of two types of ceramics, were prepared to test the hypothesis. Twenty specimens were assigned to each ceramic group: lithium disilicate (LiSi2) (e.max CAD MT, A2, IvoclarVivadent) and feldspathic ceramic (FP) (VITABLOCKS Mark II, A2C, Vita). They were prepared by sectioning the CAD/CAM blocks into 2-mm-thick slices (12x14 mm), and finished/polished gradually down to 1,200 grit size. They were ultrasonically cleaned, dried, and glazed using their respective glazes according to manufacturers’ instructions. Four intact human enamel surfaces (E) served as a control group. Baseline surface gloss was measured with a Glossometer (Novo-Curve, Rhopoint Instruments, East Sussex, UK) from 3 spots on each specimen. Five specimens from each group were randomly assigned to one of the four groups of the following prophylactic polishing pastes: Proxyt coarse/fine (PC/PF) (IvoclarVivadent), Nupro coarse/fine (NC/NF) (Dentsply). They were applied to the specimens by a calibrated/blind operator using un-impregnated prophylactic cups according to the manufacturers’ instructions for 40s (10 second intervals) under a constant load of 400gr at 3,000rpm. Surface gloss of the specimens were re-measured. A mixed, general linear model was used for statistics, and significance was accepted at p <0.05. Post-hoc comparisons were conducted using Tukey test. Results: A significant difference was found between ceramic surfaces [F(2, 32) = 17.71, p = 0.041, η2 = 8%] and prophy pastes [F(3, 32) = 76.37, p < 0.001, η2 = 40%], but no difference between the interaction of material by prophylactic pastes [F(6,32) = 1.04, p = 0.416, η2 = 5%]. Reviewing the effect size estimates (eta-squared) indicates that prophylactic paste had the greatest effect on gloss. Conclusions: Nupro Coarse reduced gloss significantly on all materials, particularly on LiSi2. Proxyt Fine reduced the least amount of gloss on all surfaces, particularly on enamel.
IADR/PER General Session
2018 IADR/PER General Session (London, England) London, England
2018 0105 Dental Materials 7: Color and Appearance (Esthetics)
Alsharari, Thani
( Nova Southeastern University
, Ft. Lauderdale
, Florida
, United States
)
Garashi, Mehdi
( Kuwait Ministry of Health
, Hollywood
, Florida
, United States
)
Hardigan, Patrick
( Nova Southeastern University
, Ft. Lauderdale
, Florida
, United States
)
Antonson, Sibel
( Nova Southeastern University
, Ft. Lauderdale
, Florida
, United States
)
NONE
Oral Session
Color and Appearance (Esthetics) I
Wednesday,
07/25/2018
, 09:30AM - 11:00AM
Table 1
Substrate
Prophylactic Paste
Mean Gloss Difference
Significance
E
PF
-0.8
a
FP
PF
-1.25
a
FP
NF
-1.39
a
LiSi2
PF
-1.74
a
LiSi2
NF
-2.08
a
FP
PC
-2.21
a
E
NF
-2.63
ab
FP
NC
-3.29
ab
LiSi2
PC
-3.41
ab
E
PC
-3.83
ab
E
NC
-4.43
ab
LiSi2
NC
-6.23
b
Groups not connected by the same letter are significantly different