A less expensive alternative to either a veneer or a crown for a front tooth, is a process called bonding. A tooth-colored filling material is applied to the tooth, shaped, hardened and polished. Bonding can be used to improve the color of a tooth, or close unsightly gaps.
Bonding is not as permanent a process as a crown or a veneer, and can be vulnerable to the same kind of staining your natural teeth are prone to. Bonding can also be more prone to chips, cracks and breakage.
Veneers or crowns are generally preferred to bonding.