Analysis of potential influencing factors for acoustic quality in patients with ectodermal dysplasia

Subjects with ectodermal dysplasia (ED) suffer from an inherited disorder in the development of ectodermal structures. They show a significantly reduced formation of teeth, hair, and a reduced number and activity of sweat and salivary glands. Recently, the voice of ED subjects has come into focus. It is assumed that the generally reduced glandular function is responsible for the altered vocal sound, although no specific cause has been identified. Previous findings included significant changes in the acoustic quality, the parameters derived from high-speed videoendoscopy, the laboratory analysis and rheological analysis of saliva samples as a substitute for laryngeal mucus. Based on these findings, we performed an extended statistical analysis directed towards the correlations between the different affected domains in order to reveal the contributing factors for the resulting acoustic voice quality. Although there were distinct statistical differences between ED males and male controls in the individual domains, only few statistical correlations were found between the subdomains i.e., acoustics, vocal fold vibrations and saliva composition/consistency. These results do not yet allow any definitive conclusions on the influencing factors of voice quality. A larger group of test subjects and analyses of the laryngeal mucus are required.