Immediate versus early loading of flapless-placed implants supporting maxillary full-arch prostheses: a randomised controlled clinical trial

Purpose: To evaluate the efficacy of flapless placed implants immediately or early loaded at 2 months with full-arch prostheses. Materials and methods: Thirty patients were randomised: 15 to the immediately loaded group and 15 to the early loaded group. All implants had to be inserted with a minimum torque > 48 Ncm. Outcome measures were prosthesis and implant failures, biological and biomechanical complications, peri-implant marginal bone level changes, patient satisfaction and implant stability quotient (ISQ) assessed with a resonance frequency analysis instrument. Results: Ninety implants were placed in the immediately loaded and 87 in the early loaded group. Four localised flaps had to be elevated. Six implants in five patients did not reach the planned insertion torque. Four were immediately replaced by larger diameters ones, one was early loaded and another removed just after placement. After 1 year no drop-out occurred. One implant failed in the immediately loaded group versus three early loaded implants in two patients. There were no statistically significant differences between groups for implant losses, complications, and mean marginal bone level changes. There were borderline significant differences for mean ISQ values, and patients in the immediately loaded group were significantly more satisfied than those early loaded. When comparing mean ISQ values taken 2 months after placement with year 1 data within each group, values increased significantly. Conclusions: Maxillary cross-arch prostheses can be successfully loaded the same day of flapless implant placement, increasing patient satisfaction while decreasing treatment time and patient discomfort. No apparent advantages were seen when loading implants at 2 months. Parole chiave: dental implants, edentulous maxillae, early loading, flapless, immediate loading