Bone density assessments of dental implant sites: 1. Quantitative computed tomography.
OBJECTIVE
This study was designed to evaluate variations of bone density in designated implant sites using quantitative computed tomography (QCT) and to compare the QCT measurements to subjective evaluation of bone density.


METHODS
Sixty-two designated implant sites in jaws of 9 human cadavers were used. Indicator rods, 2 mm in diameter, were placed in all sites. CT images representing 1-mm buccolingual slices immediately mesial and distal to the rods were selected. Bone density (in Hounsfield units) was assessed in a standardized implant area superimposed on the images and was also subjectively evaluated by 2 independent examiners using the Lekholm and Zarb classification.


RESULTS
QCT results demonstrated that bone densities may vary markedly when different areas of a designated implant site are compared. The Lekholm and Zarb ratings for the 2 examiners showed coefficients of correlation ranging between 0.5 to 0.7 for the relationships with the QCT values. Within each of the scores used for the subjective classification, however, a wide range of QCT values was observed.


CONCLUSIONS
The results emphasize the importance of the use of radiographic methods prior to implant placement that allow topographically precise assessments of bone density in the region of interest.


CONCLUSIONS
Access to QCT values should constitute a valuable supplement to subjective bone density evaluations prior to implant placement.
Shahlaie
Masih
M
Advanced Education Program in Periodontics and Implant Surgery, School of Dentistry, Loma Linda University, Loma Linda, California 92354, USA.
Gantes
Bernard
B
Schulz
Eloy
E
Riggs
Matt
M
Crigger
Max
M
D000704:Analysis of Variance; D015519:Bone Density; D015921:Dental Implants; D006801:Humans; D007575:Jaw, Edentulous / Q000000981:diagnostic imaging*; D015588:Observer Variation; D010347:Patient Care Planning; D015203:Reproducibility of Results; D036542:Tomography, Spiral Computed
D015921:Dental Implants