The most accurate method to assess bone level is the histometric measurement. However it causes discomfort in patients and damage to the regenerated tissues. in the present study, we used 4 type regenerative therapies. The present study evaluated the clinical reliability and accuracy of bone probing measurements and radiographic bone level in the assessment of bone level by comparing those results with histometric confirmed bone level.

Twentyfour(24) intrabony defects(4×4mm 1-wall intrabony defects) were surgically created in the mandibular second and fourth premolars of 6 beagle dogs. The control group underwent a conventional flap operation. Experimental group 1 was treated with calcium phosphate glass only, and while experimental group 2 was treated with GTR and experimental group 3 was treated with calcium phosphate glass and GTR. The subjects were sacrificed 8 weeks after the operation and a bone probing measurements, radiographic measurement and histometric measurement was performed.

The correlation between bone probing measurements(BP) and histometric measurement(HL), and radiographic measurement(RL) and histometric measurement(HL) were analyzed with Spearman's rank correlation analysis and the statistical significance with respect to the type of regenerative therapies was analyzed with the Kruskal Wallis test.

The coefficeint of correlation to HL was 0.73 for RL and 0.90 for BP. The type of regenerative therapies had no significant effect on the difference between HL and other measurements.

The results of this study suggests that bone probing measurements most closely represents actual bone level. So bone probing measurements may be a good clinical method for assessing the bone level following any type of periodontal regenerative therapies.