Objectives: The aim of this prospective study was to evaluate clinical and radiographic outcomes of four implants placed in extraction sockets or healed residual ridges and immediately loaded with maxillary All on 4 fixed restorations
Materials and methods: The study group comprised 6 patients who had terminal dentitions in the maxillary jaw and received 4 immediate implants (according to the All-on-4 protocol) in extraction sockets and the gap between implants and sockets was filled with bone graft. Control group composed of 6 participants who had completely edentulous healed maxillary ridges and case matched to study group, then received 4-implants without any bone grafting. For both groups immediate loading of the implants was performed by modified maxillary dentures. Six months later, final porcelain fused to metal fixed screw retained prosthesis was constructed. Clinical and radiographic outcomes of the implants were collected after, 6 months and 12 months after insertion.
Results: Implant survival rate was 91.7% and 95.9% for test and control groups respectively. For both groups, plaque and gingival scores significantly increased from base line to 6 months, then significantly decreased again. Implant stability significantly decreased from baseline to 6 months, then significantly increased later. Depth of probing and peri- implant bone loss significantly increased with time. Study group recorded significant higher plaque scores, depth of probing and peri- implant bone loss than control group after 6 and 12 months. Control group recorded significant higher implant stability than study group after 6 months