QCD sum rules for<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mi>D</mml:mi></mml:mrow></mml:math>and<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mi>B</mml:mi></mml:mrow></mml:math>mesons in nuclear matter

QCD sum rules for $D$ and $B$ mesons embedded in cold nuclear matter are evaluated. We quantify the mass splitting of $D\ensuremath{-}\overline{D}$ and $B\ensuremath{-}\overline{B}$ mesons as a function of the nuclear matter density; extrapolated to saturation density it is in the order of 60 and 130 MeV, respectively, driven essentially by the condensates $\ensuremath{\langle}{q}^{\ifmmode\dagger\else\textdagger\fi{}}q\ensuremath{\rangle}$, $\ensuremath{\langle}{q}^{\ifmmode\dagger\else\textdagger\fi{}}g\ensuremath{\sigma}\mathcal{G}q\ensuremath{\rangle}$, and $\ensuremath{\langle}\overline{q}q\ensuremath{\rangle}$. The poorly known condensate $\ensuremath{\langle}{q}^{\ifmmode\dagger\else\textdagger\fi{}}g\ensuremath{\sigma}\mathcal{G}q\ensuremath{\rangle}$ may leave room for an even larger $D\ensuremath{-}\overline{D}$ mass splitting. The genuine chiral condensate $\ensuremath{\langle}\overline{q}q\ensuremath{\rangle}$, amplified by heavy-quark masses, enters the Borel transformed sum rules for the mass splitting beyond linear density dependence. The inclusion of strange quark condensates reveals a numerically smaller and opposite effect for the ${D}_{s}\ensuremath{-}{\overline{D}}_{s}$ mass splitting.