Compared to studies with conventional maintenance, relatively few studies have been conducted that have tested pharmacologic intervention as a means for supportive periodontal care. Despite the scarcity of data, several principles have begun to emerge. First, it is clear that removal of subgingival calculus is necessary for the highest level of a long-term effectiveness. Hence, pharmacologic intervention appears best suited as an adjunctive therapy directed toward ''problem sites''; sites that fail to respond adequately to conventional maintenance procedures. Intrapocket drug delivery systems appear to offer particular promise since therapy can be directed to selected sites that appear to be failing. Additional effectiveness may also be obtained by use of chlorhexidine mouth rinses for short periods of time during healing to control re-infection. Eradication of reservoirs of infection throughout the mouth also appears to be an important principle related to long-term stabilization. Studies to date suggest that superior clinical response can be obtained by intrapocket delivery systems. Furthermore, up to 2 years of periodontal stabilization can be achieved by these means and longer disease-free maintenance intervals can be established. Additional clinical trials will be necessary to fully optimize and understand this therapeutic approach, but initial studies have reported promising results.
