RESUMO
BACKGROUND: The chemical, physical, and morphologic characteristics of the implant surface play a fundamental role during the osteointegration process. Implant design is of paramount importance in determining implant primary stability and implant ability to sustain loading during and after osteointegration. LASER treatment of the surface allows defining the precise parameters of roughness to obtain a regular and repeatable surface in total absence of contamination. PURPOSE: The aim of this study was to analyze the behavior of implant stability of LASER-treated surface implants by repeated resonance frequency analysis (RFA) measurements during 2 years in patients with complete upper maxilla edentulism subject to an immediate-loading protocol. METHODS: Ten patients were included, and each treated with the insertion of 6 or 8 LASER surface implants according to the individual surgical-prosthetic planning. During the bone drilling and implant insertion, torque values were monitored with a specific handpiece and software. All implants were loaded within 24 hours from the insertion with the application of a temporary full-arch prosthesis. Subsequent follow-up has been done at 24 months from the loading with radiographic controls (OPT) and RFA measurement on all implants at time of implant insertion and at 1, 3, 6, 12, and 24 months from loading. RESULTS: Resonance frequency analyses at 3 and 6 months from the implant loading have shown a rapid increment of implant stability quotient (ISQ) values in the first phases of bone remodeling, subsequent to the peri-implant bone remodeling. The paired comparisons between mean ISQ values by patient showed a statistically significant decrease in primary stability from baseline up to 1 month (P = 0.0039). Subsequent measurements revealed a statistically significant increase in implant stability from 1 up to 3 months (P = 0.0156), from 3 up to 6 months (P = 0.0020), from 6 up to 12 months (P = 0.020), and 12 up to 24 months (P = 0.0391). CONCLUSIONS: Resonance frequency analysis of the LASER-treated surface implants showed good ISQ values at all time point measurements. These results are consistent with data from literature on the analysis of RFA in protocols of immediate loading at the upper maxilla.