Fig. 1

Flow-chart of participants. One hundred six participants were included for the study. Due to administrative protocol deviations, three patients from both groups were immediately excluded. Three additional patients of the MB group received wrong implant. Forty-seven patients in the MB and 50 patients in the FB group were available for the baseline data. Forty-two patients in the MB group and 48 patients in the FB group were available for the 5-year follow-up