Recent results of a limited clinical trial suggest that mechanical root scaling and root planing therapy alone may not be the most effective mode of treatment for patients affected by moderate to severe adult periodontitis. However, scaling and planing combined with laser therapy utilizing a low-powered pulsed Nd:YAG laser have been shown to be successful in the elimination of the bacteria commonly associated with the development of this oral condition. The double-blind, split mouth design study involved 10 human subjects randomly assigned to one of three treatments: 1) scaling and root planing alone, 2) dental laser plus scaling and root planing, and 3) control only. This article presents the clinical results of the trial, which suggest that laser therapy is a viable adjunct to local, nonsurgical therapy such as scaling and planing.