Laser-Doppler microvascular measurements in the peri-implant areas of different osseointegrated bone conductor implant systems.

The objective of this study was to evaluate the impact of hydroxyapatite coating of newly designed osseointegrated fixtures' abutments on the postoperative complication rates. The integrity of peri-implant microcirculation was used as a marker to compare tissue viability after different surgical techniques. Laser-Doppler Flowmetry (LDF) measures alone, and coupled with heat provocation tests were applied to test the different microcircular patterns. Measures for 17 consecutively implanted patients (8 women, 9 men, ages ranged from 18 to 77 years) were recruited; seven with soft tissue reduction (STR); and 10 with soft tissue preservation (STP).Thirteen non-operated retro-auricular areas were examined as naive controls. In isotherm conditions the baseline blood flow remained stable in all groups. The naive control patients demonstrated significant changes of blood flux in the intact skin. The non-implanted yet previously operated contralateral sides of the patients demonstrated marginally lower (p = 0.09) blood flux index. The STR sides however, showed significantly lower (average 217 %) provoked blood flux compared to controls (p < 0.001). At the STP sides a maladaptation could be observed (average 316 %) compared to the contralateral sides (p = 0.53). STP sides demonstrated a significantly better blood flow improvement compared to the STR sides (p = 0.02). These results suggest a favorable postoperative condition of vascular microcirculation after STP, than after STR surgery. The possibly faster wound healing and lower potential complication rate may widen the inclusion criteria and maybe beneficial for the patient compliance with a better quality-of-life.