This study proposes a new clinical procedure for measuring the closest speaking space (CSS) and compares it with an instrumental method. The study population included 15 edentulous and 10 dentulous subjects free of systemic disease, speech defects, or masticatory system dysfunction. For all subjects, the CSS was measured using clinical and instrumental methods. The clinical method utilized polyvinyl siloxane, commonly used for interocclusal records, injected on the occlusal surface of the premolars just before the pronunciation of a word containing the consonant sound "s" 3 times. The instrumental method used a kinesiograph. Statistical analysis was performed using 1-way repeated-measures analysis of variance and the Student t test for paired data. There was no statistical difference between the clinical and instrumental methods of determining CSS. Within the limitations of this study, based on a small sample, the new simpler and less expensive method to record the CSS should be considered and further investigated.