The residual edentulous arches--foundation for implants and for removable dentures; some clinical considerations. A review of the literature 1954-2012.

The maxillary and mandibular arches are present before tooth eruption and will develop and mature with tooth activities. Following tooth extraction, the healing wound fills in, partly, the space occupied formerly by the natural tooth. The blood coagulum that occupies the healing wound will be replaced by the residual ridge, a scar tissue, which becomes part of the edentulous arch. After tooth loss, the resulting edentulous arches undergo extensive remodeling changes, but remain indispensable, vital oral structures. The resorptive process of the edentulous jaws is limited. The maxillary and mandibular bodies have never been known to recede completely. Furthermore, physiological spontaneous fracture of the jaws does not occur. One factor that helps preserve the jaws' integrity may be the enveloping muscle girdle attached to the external surfaces of the jawbones. The residual ridge develops after tooth extraction and continues to remodel, during the edentulous life of the individual. The ridge resorption is a chronic, progressive, irreversible process. The residual ridge may even disappear as an anatomic entity following an extended edentulous period, systemic and/or local factors. Resorption of the residual tissues seems to be hastened by, systemic affections, edentulousness time, denture wear, tobacco consumption and other unknown factors. In the edentulous patient, the maxillary ridge migration is centripetal and apical, whereas in the mandible, the remaining ridge shifts centrifugally and apically. Consequently the resulting edentulous maxillary arch is, mostly, internal or at the same vertical level with the facing toothless mandibular arch. The different individual inter arch spatial relations are to be considered for the positioning of the artificial teeth, for optional ridge augmentation procedures and for insertion of dental implants.