Implants and sinus-inlay graft in a 1-stage procedure in severely atrophied maxillae: Prosthodontic aspects in a 3-year follow-up study

The aim of this 3-year prospective study was to evaluate the prosthetic tre atment in 2 groups of maxillary edentulous patients with similar age and ge nder distribution: a study group of 39 patients treated with intra-sinus bl ock bone grafts and implants in a 1-stage procedure, and a control (referen ce) group of 37 patients treated with implants and no grafting. In the stud y group, bone volumes were regarded as insufficient for implant treatment u nless a bone grafting procedure was performed (posterior alveolar bone heig ht was less than 5 mm). Self-tapping Nobel Biocare implants were used in bo th groups of patients. In the study group, 35 fixed partial dentures and 4 overdentures were placed, and in the control group 34 fixed partial denture s and 3 overdentures were placed. All patients were followed for at least 3 years. The 3-year follow-up examination included examination of a number o f clinical parameters as well as the type of abutment and evaluation of sta bility of prosthesis retention screws and abutment screws. During the follo w-up period, 2 patients were lost from the study group and 4 patients from the control group, giving a total of 70 patients available for examination after 3 years (8% dropout rate). Both the amount of plaque and gingival ble eding were significantly lower in the study group than in the control group . The presence of attached gingiva was 25% in the study group and 35% in th e control group. The number of angulated abutments was significantly higher in the study group than in the control group. There was no significant dif ference in the number of prosthetic complications in the 2 groups of patien ts. Neither was there any significant difference in prosthesis screw or abu tment screw stability between the 2 groups. The type of abutment did not si gnificantly influence the stability of prosthesis retention screws or abutm ent screws in either of the groups. However, prosthesis screw stability was significantly greater than abutment screw stability in both groups of pati ents. It can be concluded that the prosthetic outcome was similar in the 2 groups of patients, regardless of whether or not a bone grafting procedure was used.