Resonance Frequency Analysis Applied to Different Implant Surfaces

Objectives: It is unkown what effect the amount of bone adjacent to an implant has on resonance frequency analysis (RFA). The purpose was to evaluate any difference in RFA values as measured from the buccal (B) or mesial (M) aspect of an implant, and the impact of the ridge width in these measurements.

Methods: Ninety seven implants were placed in the mandible of 17 minipigs. The width of the healed ridge was measured using a UNC 15 periodontal probe. Ridge measurements were taken at the most posterior and anterior aspects of the ridge. Implants were placed at least 3 mm from one another, and RFA was done using the Osstell Mentor instrument. Three measurements were made on the B and M aspect of each implant. ANOVA was applied to evaluate differences in measurements and regression analysis performed to determine impact of ridge width.

Results: The RFA measurements on each side were averaged to obtain a mean B and M RFA value. A statistically significance difference (p<0.006) was identified between RFA measurements taken from the B and M aspects of the implants. The RFA value on the M was greater than the B in 79 of 96 implants, equal values at 4 implants, and B values greater at 13 implants. Ridge width had no significant effect (p<0.096) on the measurements taken from the B or M. The mean posterior and anterior ridge widths were 6.16 mm (range 3-11 mm) and 3.75 mm (range 2-6 mm ), respectively.

Conclusions: RFA produces considerably different results when it is applied to the B versus M aspect of an implant. The significant difference in RFA values were not a result of variances in ridge width, although the ridges may not have been wide enough to show a statistical difference in this animal model.