This study was undertaken to examine histologically the healing response of alveolar bone following removal of granulation and/or connective tissues from interproximal craters by manuel curettage or ablation by carbondioxide laser. The time required to complete each type of degranualtion procedure was also compared. Four interproximal treatment sites in each quadrant of two dogs were randomly assigned to each treatment modality. Neither treatment modality was totally effective in removing all suprabony connective tissue. Healing was clinically uneventfula and histologically similar for both treatment groups at all time intervals. Lasr-treatedspecimines exhibited little of no inflammatory cell infiltrate, areas of heat-induced tissue necrosis, accumulations of Carbonized debirs that initially was surroundex by macrophages and eventually phagocytized by multinucleated giant cells, and spiceles of nonvital boe that exhibited a surface layer of osteoid. Although manual curettage was found to be statistically significantly faster, the difference between mean times was roughly 55 seconds and therfore unlikely to be clinically significant.