2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/229810We use the spanning tree model for Khovanov homology to study Legendrian links. This leads to an alternative proof for Ng's Khovanov bound for the Thurston-Bennequin number and to both a necessary and a sufficient condition for this bound to be sharp.This is the version published by Algebraic & Geometric Topology on 21 October 2006Geometric TopologySymplectic Geometry57M25, 57R17text