The comparative benefits from the use of sodium bicarbonate and hydrogen peroxide over the use of a commercial dentifrice in periodontal therapy is controversial. The consensus of the clinical research indicates that application by patients of sodium bicarbonate and hydrogen peroxide offers no advantage over the preestablished, properly performed home oral hygiene procedures. Any improvements in clinical and microbial parameters generally were attributed to scaling and root planing. The studies that have reported beneficial results with sodium bicarbonate and hydrogen peroxide have used additional antimicrobial agents, concomitant professional application of these substances, and scaling and root planing. In one of these reports, inorganic salts and chloramine-T were delivered subgingivally throughout root-planing procedures, in addition to home application of inorganic salts. Most of these patients also received at least one course of systemic tetracycline therapy. Because this study had no control group, it is impossible to determine whether this program is more effective than are other periodontal therapy programs. A more controlled clinical study involving professional application of sodium bicarbonate, sodium chloride, hydrogen peroxide, and povidone-iodine has shown greater gains in clinical attachment and bone mass than has brushing with toothpaste and water. Again, subgingival scaling and root planing were necessary to attain these results. Because multiple topical agents were applied in both of these reports and systemic antimicrobial agents were used by the Keyes group, it is impossible to determine which agent was responsible for the improvements. Further, professional application may be the crucial factor.(ABSTRACT TRUNCATED AT 250 WORDS)