ABSTRACT
Objectives: Computer-aided design (CAD) and manufacturing (CAM) allows the milling
of high strength zirconia fixed partial dentures (FPD), however bonding to an inert
ZrO2 ceramic surface may effect the marginal integrity of the FPDs. The aim of this
investigation was to evaluate the marginal adaptation of zirconia FPDs at the interfaces
between zirconia, cement, and tooth.
Methods: Methods: 32 3-unit FPDs were fabricated of the CAD/CAM Y-TZP zirconia (Lava,
3M Espe, Germany) according to the manufacturers’ instructions. Resin cements with
corresponding primer and bonding systems were used to lute the FPDs: Compolute/EBS
multi (3M Espe, Germany), Panavia F/ED (Kuraray, Japan), Variolink 2/Syntac classic
(Ivoclar-Vivadent, FL) and RelyX Unicem/without treatment (3M Espe, Germany). Au-alloy
FPDs (BioPontostar, Bego, Germany) were cemented with RelyX Unicem and Harvard (Harvard,
Germany) as the control. Marginal adaptation was evaluated with scanning electron
microscopy using replica specimen before and after artificial aging. After aging,
microleakage tests were performed with fuchsine solution. The interfaces between cement-tooth
and cement-FPD were examined.
Results: At the interfaces (cement-tooth and cement-FPD), the systems showed a 95%
or higher perfect margin before and after aging. Only Variolink2/Syntac had a marginal
adaptation, lower than a 70% perfect margin. Generally, the fuchsine penetration was
below 20%, only BioPontstar/Harvard and Lava/Variolink2 showed penetration results
between 80% and 100%.
Conclusion: The success of the adhesive cementation of zirconia FPDs depends on the
cement system. Under the conditions of this study, zirconia FPDs showed good to sufficient
marginal integrity in combination with Panavia/ED, Compolute/EBS and RelyX Unicem.
(Eur J Dent 2007;1:25-30)
Key words
CAD/CAM - Marginal integrity - Microleakage - Zirconia