By considering five-dimensional cosmological models with a bulk filled with a pressureless scalar field or equivalently dust matter, and a negative cosmological constant, we have found a regular instantonic solution which is free from any singularity at the origin of the extra coordinate. This instanton describes the five-dimensional asymptotically anti-de Sitter wormhole, when the bulk has a topology R × S⁴. Compactified braneworld instantons which are built up from such an instantonic solution describe either a single brane or a string of branes. Their analytical continuation to the pseudo-Riemannian metric can give rise to either four-dimensional inflating branes or solutions with the same dynamical behaviour for extra dimension and branes, in addition to multitemporal solutions. Dust braneworld models with arbitrary dimensions (D ≥ 5) as well as other spatial topologies are also briefly discussed.