Surgical and Prosthetic Rehabilitation of Combination Syndrome

The aim of this report is to analyze the clinical symptoms, ethologic factors, and prosthetic rehabilitation in a case of Combination Syndrome (CS). The treatment of CS can be conventional or surgical, with or without the bone reconstruction of maxilla. The correct prosthetic treatment helps this kind of patients to restore the physiologic occlusion plane to allow a correct masticatory and aesthetic function. Management of this kind of patients can be a challenge for a dental practitioner. 1. Introduction The seventh edition of the Glossary of Prosthodontic Terms defines Combination Syndrome (CS) as “the characteristic features that occur when an edentulousmaxilla is opposed by natural mandibular anterior teeth, including loss of bone from the anterior portion of the maxillary ridge, overgrowth of the tuberosities, papillary hyperplasia of the hard palate’s mucosa, extrusion of the lower anterior teeth, and loss of alveolar bone and ridge height beneath the mandibular removable partial denture bases—also called anterior hyperfunction syndrome” [1, 2]. This matches the findings of Kelly on the pattern of residual ridge resorption as observed in a group of patients completely wearing maxillary dentures opposing distal extension removable partial dentures (RPD). Saunders noted an associated loss of vertical dimension of occlusion, occlusal plane discrepancy, anterior repositioning of the mandible, poor adaptation of the prostheses, epulis fissuratum, and periodontal changes [3]. Kelly considered the early bone loss in the anterior maxilla to be the key to the other changes and noted that as resorption of the premaxilla progressed, further tissue damage and denture instability followed proportionately [2, 4, 5]. The changes in tissue form and health seen in Combination Syndrome can be attributed to several factors. When mandibular anterior teeth are present, patients tend to favor these teeth functionally because of the ability to produce maximum force. Excessive anterior functional and parafunctional forces, particularly when not counterbalanced posteriorly in excursive movements, constantly overload the anterior ridge to result in alveolar bone resorption [2, 6, 7]. As bone and ridge height are lost anteriorly, tuberosities in the posterior site will often enlarge and grow downward. One theory suggests that negative pressure within the maxillary denture pulls the tuberosities down as the anterior ridge is driven upward by the anterior occlusion. The functional load will then direct stress to the mandibular distal extension and cause bony resorption of the