Fully vs. partially rough implants in maxillary sinus floor augmentation: a randomized-controlled clinical trial

Objectives: To compare implants with a rough surface in their whole length (FR) with implants having a 2 mm coronal machined portion (PR) when used in association with a sinus-lift procedure.

Material and methods: Twenty-six patients with 2 mm≤x≤9 mm residual alveolar crest were prosthetically restored with implants after a staged sinus-lift procedure using osteotomes. In 13 randomly chosen patients, no more than one FR implant was placed (test group), while the rest were PR implants. The other 13 patients received only PR implants (control group). For comparisons, only one implant from each patient was used, i.e., from the test group only the 13 FR implants were used, while from the control group, one PR implant was randomly chosen. The presence/absence of plaque, BOP, PPD and REC were registered at the day of delivery of the restorations and after 1 year. Residual alveolar crest height and marginal bone levels around the implants were evaluated on standardized periapical radiographs taken at various stages.

Results: Four FR and two PR implants were lost, and the cumulative survival rate was 82.9% (six lost out of 35). There were no significant differences between the two groups. Implant type, residual alveolar crest height, time of osseointegration, time of implant loading and smoking did not seem to influence implant survival.

Conclusions: FR and PR implants placed in augmented sinuses did not differ in their clinical performance.