Introduction Velopharyngeal sphincter is a portion of the muscle of the palatopharyngeal arch that is capable of separating the oral cavity from the nasal cavity. It has not been determined yet whether voice intensity has an influence on this capacity. Velopharyngeal sphincter closure is accomplished by elevating and retracting the soft palate at the same time as the nasopharyngeal walls are constricted.

Objective This study aims to correlate voice intensity with velopharyngeal sphincter closure in individuals without velopharyngeal dysfunction and patients with cleft lip and palate.

Methods We conducted a cross-sectional, comparative, and contemporary study. The sample consisted of 16 individuals in the control group and 16 individuals in the study group. Patients underwent instrumental assessment, which we subsequently analyzed using a computer program, and a brief medical history review. The mean age of the control group was 27.6 years, whereas the mean age of the case group was 15.6 years.

Results Cases showed higher voice intensity in regular and weak fricative sentences when compared with controls. There was no agreement on the analysis of the instrumental assessment between the assessors and the computer program. Regardless of voice intensity, the computer program demonstrated a similar closure pattern.

Conclusion The computer program showed similar closure pattern for the three levels of intensity. There was no agreement between the three assessors and the closure pattern determined by the computer program. There was no statistically significant correlation between voice intensity and degree of velopharyngeal sphincter closure.