Light Transmission Through Different Types of Zirconia-Ceramic Frameworks

^{Objectives: The purpose of this study was to quantify the light transmission of different zirconia-ceramic framework materials.}

^{Methods: Disk shaped specimens were fabricated in three clinical relevant thicknesses (0.3, 0.5, 1.0 mm) of various types of zirconia-ceramics with comparable color: ZPS) TZP-A porously sintered (Lava, 3M ESPE), ZHIP) TZP-A BioHIP (Metoxit), ZNAN) Nano Zr, ZACF) Zirluna (ACF). Light transmission through specimens (3/group) was determined in a spectrophotometer with an integrating Ulbricht sphere (Lamda35, UV-VIS, PerkinElmer) by measuring the transmission coefficient (tc) [%] for wavelengths from 400 to 700 nm. Overall tc was calculated by evaluating the integral ∫400-700 tc (l) dl [10-5].}

^{Results: Given as mean values of overall tc (SD):}

^{ANOVA showed significant (p<0.05) differences among overall tc values depending on zirconia-ceramic type (p<0.001) and thickness (p<0.001). Post-hoc test indicated statistic differences between the 3 different thicknesses (Student-Newman-Keuls). Statistic differences were detected between ZNAN, ZHIP and ZACF/ZPS (Student-Newman-Keuls).}

^{Conclusion: Especially Nano-Zirconia showed significantly lower translucency. Given to the high masking power ZNAN should be preferred in cases with severely discolored abutments.}

^{This study was partially supported by 3M ESPE}