Evaluation of bone-implant integration: Efficiency and precision of 3 methods

Computer-assisted planimetry, computer-assisted lineal analysis, and point- counting stereology have been compared with respect to their reproducibilit y and the time required to analyze bone-implant integration. Sections of 6 threaded dental implants selected from a bone augmentation experiment for t heir wide range of new bone formation were analyzed by each method 3 times. The bone density and percentage of osseous integration were evaluated at 4 sites around each implant section. It was found that computer-assisted pla nimetry demonstrated a modest but significantly greater variance (P < .05) in bone density estimates when compared to the computer-assisted lineal ana lysis and point-counting methods. Computer-assisted planimetry requires a d ifferent method of measuring each parameter and separate fields of view to evaluate fields distant from the implant. However, this can all be accompli shed with line probes, as in computer-assisted lineal analysis, which exten d from the implant surface into the surrounding alveolar bone. Whereas comp uter-assisted planimetry requires a separate identification of the perimete r of each field to be analyzed (next to and distant from the implant), comp uter assisted lineal analysis allows expansion of the field to be evaluated without creating a new field of view. Also, following a limited learning c urve, both point-counting and computer-assisted lineal analysis required le ss time to complete than did computer-assisted planimetry.