Early marginal bone loss around immediately loaded one-piece and two-piece dental implants following immediate or delayed loading. A prospective study

Aim This study was conducted to evaluate the marginal crestal bone loss around immediately loaded one-piece vs. two-piece dental implants associated with two different loading protocols during the first year after implant insertion.  Materials and methods Eighty-six patients participated in the study; 90 dental implants (Zimmer Dental) were used. Of those, 30 were Tapered Screw Vent (TSV) implants with an immediate loading protocol (TSVi), 30 TSV with delayed loading (TSVd), and 30 were one-piece implants with an immediate loading protocol (OP). Crestal marginal bone loss in the coronal area of dental implants was evaluated radiographically at three months and one year post-implant insertion.  Results Marginal bone loss was significantly higher after one year post-surgery compared to three months post-surgery in all the study groups. The mean values of marginal bone loss obtained by TSV implants were higher than those obtained with OP implants at both follow-up points. TSVd implants experienced the higher crestal marginal bone loss among all the study groups at both three months and one year.  Conclusions Crestal marginal bone loss in the most coronal part of one-piece implants  is significantly less than the marginal bone loss observed in tapered screw vent  implants with either immediate or delayed prosthetic loading protocols with single implant crown rehabilitations. However, further studies with a longer observational time and  larger sample  are necessary.