The present study evaluates the effects of calcium sulfate and DFDB on alveolar bone regeneration and cementum formation and connective tissue adhesion in intrabony angulated 1 wall defects of dogs. Four millimeter-deep angulated one-wall intrabony defects were surgically created in the mesial & distal aspects of premolars and with flap operaion alone(control group), with calcium sulfate(experimental group 1), with composit graft of 50% calcium sulfate and 50% DFDB(experimental group 2), with DFDB alone(experimental group 3). Histologic analysis following 8 weeks of healing revealed the following results:

1. The lengths of connective tissue adhesion was 1.05±0.48mm in the control, 1.30±0.67mm in the test group I, 0.97±0.22mm in the test group II and 0.93±0.15mm in the test group III. There was no statistical significance between control and all experimental groups.

2. Changes in alveolar bone level was 0.97±0.27mm in the control group, 1.45±0.42mm in the test group I, 2.00±0.33mm in the test group II , 1.88±0.34mm in the test group III. There was no statistically significant difference between control and experimental group I. There was a statistically significant difference between the control and experimental group II,III.(p<0.05). There was no statistically significant difference between all experimental group.

3. Cementum formation was 1.13±0.17mm in the control, 1.78±0.31mm in the test group I, 2.17±0.38mm in the test group II, 2.15±0.47mm in the test group III with statistically significant differences between control group and all experimental group(P<0.05). There was no statistically significant differences between all experimental group.

These results suggest that the use of composit graft of 50% calcium sulfate and 50% DFDB and DFDB alone in angulated 1 wall intrabony defects has little effects on connective tissue adhesion, but has significant effects on new bone and new cementum formations.