RESUMEN
Objective The study examined the influence on marginal bone levers at implants which implants were assigned to open healing and implant-abutment connection restored according to a platform-switching concept. Methods One implant were placed in the first molar of mandible of 48 patients , randomly assigned to open (OH) or submerge (SH) healing. Standardized radiographs were obtained after implant surgery, when implant transfer and crown mounting, and 6 ,12 and 24 months after implants restoration, then evaluated for implant-bone-lever alterations(ΔIBL). Results After 6 months after implants restoration,ΔIBL were (-0.25 ± 0.08)mm mm(OH)and (-0.26 ± 0.12)mm(SH). After 12 months follow-up, ΔIBL were (-0.29 ± 0.13)mm (OH)and (-0.31 ± 0.14) mm(SH), and after 24 months later, ΔIBLwere (-0.34 ± 0.15)mm(OH)and (-0.33 ± 0.11)mm (SH). Conclusions Platform-switched implants showed very limited peri-implant bone-lever alterations. The healing-mode neither affected the total amount nor the temporal patterns of ΔIBL.