Objectives: This study quantified the light transmission through all-ceramic frameworks dependent on two luting materials (LM). Methods: Disk shaped specimens (16x0.9mm) were made of various ceramics of shade A3 (Vident): A) Densely sintered Al2O3, EX) Experimental (OHSU-RWTH,IvoclarVivadent(IV)), IA) Infiltrated Al2O3 (In-Ceram(IC) Alumina,Vident), IS) Infiltrated MgAl2O4 (IC Spinell), IAZ) Infiltrated Al2O3/ZrO2 (ICZirconia), L) Lithium disilicate (Empress2,IV), Z) ZrO2-Y2O3 (LAVA,3MESPE). Ceramic disks were covered with a 0.1 mm layer of 1) zinc phospate (Harvard Dental) or 2) dual cured resin cement (Variolink transparent,IV). As reference (
3)), uncovered 1 mm ceramic disks were employed. Samples (3/group) were tested after 30 days storage in artificial saliva. Light transmitted through the specimen was determined in a spectrophotometer (DU-7,Beckman) by direct transmission coefficient (tc) [%] for wavelengths (l ) from 400 to 700 nm. Results: Values are given as overall tc, calculated as integral 400-700 tc (l )dl ,means (SD):|
A |
EX |
IA |
IS |
IAZ |
L |
Z |
|
|
1) |
37.2 (3.0)ab |
42.9 (3.8)b |
21.6 (1.6) |
46.6 (3.2)b |
5.6 (0.7)I |
31.8 (2.8)a |
34.1 (2.3)a |
|
2) |
61.8 (5.0)c |
400.6 (34.6) |
32.4 (1.5) |
81.8 (4.0)d |
6.3 (0.9)I |
77.3 (4.9)d |
51.2 (5.8)Zc |
|
3) |
55.2 (4.4) |
301.7 (47.8) |
26.1 (0.3) |
78.5 (3.6) |
4.9 (0.6)I |
66.7 (3.0) |
45.3 (1.1)Z |
Conclusions: ANOVA showed significant (p<0.05) differences among the overall tc values dependent on type of ceramic and LM (n.s.=same superscript). Overall tc increased significantly when LM-2 was used. Higher translucency ceramics showed greater sensitivity to luting material type than the more opaque ceramics.