Crestal bone changes around early vs. conventionally loaded implants with a multi-phosphonate coated surface: A randomized pilot clinical trial.

Abstract

To compare the marginal bone level around implants with a thin multi-phosphonate coated surface after either an early or conventional loading protocol. A randomized pilot clinical trial was conducted. Dental impressions were obtained after either 4 (test) or 8weeks (control) and single crowns screwed-in 2weeks later. Several variables were evaluated including radiographical marginal bone level (MBL), patient's level variables, and those related to the restoration and surrounding tissues. These data were obtained at several time points up to a 1-year follow-up. Thirty-four patients were included in the study, 18 assigned to the test group. No differences at implant placement were detected for tissue thickness, keratinized mucosa, nor any other clinical or radiological variable. At the time of impressions, tissue was thinner in the test group (2.30 (0.46) versus 2.78 (0.66) mm, test versus control, respectively; p=.012) so shorter abutments were used in this group. Regardless, no significant changes in marginal bone level were detected neither within group along time nor between groups. The average MBL at the 1-year follow-up was -0.15 (0.32) versus -0.22 (0.37) (p=.443) (test versus control, respectively). None of the clinical or radiological variables evaluated had a determinant influence on the MBL at any visit nor group. The use of implants with a multi-phosphonate coated surface for early loading offers successful radiographical outcomes 1year after loading. MBL over time was not affected by taking the impressions 4 or 8weeks after implant placement and loading them 2weeks later.