Overhanging margins of proximal restorations are a well-known, iatrogenic cause of periodontal pathology. The high incidence of such findings in Western societies should arose the concern of the dental community. However, overhanging margins represent only part of the iatrogenic problem created by the misuse of wedges in restorative procedures. Other causes include incorrect proximal contouring, inadequate contact points and under- or overfilling the restorative material. The understanding of the variables associated with wedge selection and positioning has a major role to play in the prevention of iatrogenic periodontal pathology associated with restorative procedures. It is concluded that: (i) the occlusion of the matrix band to the remaining healthy tooth structure of the gingival cavosurface line angle should be achieved solely by the correct application of the wedges; (ii) the effect of the wedges on the proximal contour and contact area should be carefully re-evaluated prior to insertion of the restorative material; (iii) various sizes and shapes of wedges and a sharp knife for carving must be readily available.