A beautiful tiara, I'd love to see this and other noble jewels more often! The bride has three unmarried siblings, so there is hope!
The pic Stig posted is from the wedding of Prince Manuel of Bavaria & Princess Anna of Sayn-Wittgenstein-Berleburg in 2005. The Princess of Oettingen wore the tiara again a few weeks later at the wedding of Duchess Elisabeth in Bavaria & Daniel Terberger. Same dress with an added necklace: