Clinical experiences of CNC-milled titanium frameworks supported by implants in the edentulous jaw: 1-year prospective study.

Abstract

A new type of titanium framework has been introduced, but so far no clinical reports have been made in this treatment modality. The aim of this study was to report the clinical performance of implant-supported prostheses with computer numeric controlled (CNC)-milled titanium frameworks in the edentulous jaw and to compare the results with prostheses provided with conventional cast frameworks during the first year of function. A consecutive group of 65 patients with 67 prostheses were provided with CNC-milled titanium frameworks in 23 upper and 44 lower jaws. During the same period, 61 consecutive patients were treated on a routine basis with 31 upper and 31 lower conventional gold alloy casting prostheses. Clinical and radiographic 1-year data were collected for both the test and control groups. A total of 14 of 729 inserted implants were lost during the follow-up period (1.9%). All prostheses were functioning after 1 year except a conventional prosthesis with a cast framework, which was replaced by an implant-supported over-denture due to implant loss. The 1-year cumulative survival rate (CSR) was 100% and 97.8% for CNC prostheses and implants, respectively. The corresponding CSR for the control group was 98.3% and 98.3%, respectively. Few problems were reported in both groups, and the clinical and the radiologic performances were similar for both groups. No mechanical complications except some resin veneer fractures (n = 6) were observed. The mean marginal bone loss for the test group during the first year in function was 0.4 mm (SD = 0.35) and 0.4 mm (SD = 0.33) in the upper and lower jaws, respectively. A similar pattern of bone reaction was also observed in the control group. CNC-milled titanium frameworks can be used as an alternative to conventional castings in the edentulous jaw, presenting similar clinical and radiologic performances as conventional cast frameworks during the first year of function.