The decreased mouth opening (microstomia) represents a frequent finding in patients with systemic scleroderma (SSD), but little information is available about the efficacy of nonsurgical management of this condition. The aim of this study is to assess the effects of a nonsurgical exercise program on the decreased mouth opening in a group of 10 SSD patients with severe microstomia (maximal mouth opening < or =30 mm). The subjects were instructed to perform an exercise program including both mouth-stretching and oral augmentation exercises. The effects of such exercises were assessed after an 18-week period by measuring the maximal mouth opening of each subject. All patients completed the study and no adverse effects occurred, with the exception of transient muscular fatigue. The exercise program improved the mouth opening of all subjects (mean increase: 10.7+/-2.06 mm, P<0.005), without significant differences between dentate and edentulous ones (P>0.1). At the end of the 18-week period, all patients commented that eating, speaking and oral hygiene measures were easier. The edentulous subjects also experienced less difficulty inserting their own dentures. These findings suggest that regular application of the proposed exercise program may be useful in the management of microstomia in SSD patients.