Application of a barometer for assessment of oral functions: Donders space

Abstract

We developed a barometer applicable to a small space, to assess oral and pharyngeal functions. Negative oral pressure during rest and pressure changes during swallowing were measured in a space between the palate and tongue (STP). Twenty volunteers were asked to sit in a chair in a relaxed upright position. A sensor was placed on the posterior midline of hard palate. Recording commenced just before subjects closed their lips and continued. Subjects were asked to swallow saliva and keep the apposition. Finally, subjects were asked to open their mouth. Recordings were performed five times, and 5 s of continuous data in each phase was averaged. To verify the reliability of the system, the same procedure was accomplished with twin sensors. When the jaw and lips were closed, the pressure slightly decreased from atmospheric pressure (-0·17 ± 0·24-kPa). After swallowing, the pressure in STP showed more negative value (-0·50 ± 0·59-kPa). There is a significant difference between the values in open condition and after swallowing (P < 0·001) and between values after swallowing and final open condition (P < 0·05). Twin sensor showed almost the same trajectories of pressure changes for all the recordings. Obtained negative pressure might generate about 0·71-N of force and would be enough to keep the tongue in the palatal fossa at rest. The system detected large negative/positive pressure changes during swallowing. We conclude this system may be a tool to evaluate oral functions.

Development of a novel composite sensor for evaluating lip function

“…These studies reported a wide range of IPs that varied between −5 and 25 kPa, depending on the performed oral tasks. For instance, a negative IP (−0.5 kPa) occurs in the Donders space with the mandible at rest; swallowing is accompanied by a biphasic baro‐pressure variation with two sequential peaks, varying between 10 and 15 kPa depending on food viscosity; and during the production of the stop consonant /k/, IPs of 2.5, 0.7 and 1.6 kPa occur at the centre of the “Ah” line, at the incisive papilla, and at the mid‐pharynx, respectively . The IP during sound production is lower than that during swallowing .…”

“…18 The IP during sound production is lower than that during swallowing. [17][18][19] Lastly, IPs higher than the systolic pressure (about 17 kPa) have also been reported. Trumpet players may produce during blowing IPs as high as 25 kPa.…”

“…The contact force sensor and the baro‐pressure sensor were placed on each side of the polyimide film (Figure ). The details of the baro‐pressure sensor controller have been described by Hasegawa et al and Hiraki et al The signals were transmitted from the oral cavity along the polyimide film that was connected to laboratory‐made amplifiers and a micro‐CPU (H8/3694; Renesas Electronics Corporation) via a small connector. The micro‐CPU carried 10‐bit A/D converters and sent the signals to a PC via a USB.…”

“…Therefore, we developed a new device that allows simultaneous recording of these three parameters. The preliminary laboratory work involved (a) developing a small composite baro‐pressure sensor that allowed recording the pharyngeal baro‐pressure changes occurring during swallowing, oral baro‐pressure changes during speech, and negative baro‐pressure in the Donders space at rest, and (b) confirming that the EMG activity of the OOM could be recorded by placing the electrodes directly in contact with the lip mucosa, which is moistened with saliva and lacks the stratum corneum.…”

Use of a Novel Device to Assess Intraoral and Intrapharyngeal Baropressure during Sound Production

“…We recently developed a novel device using single and/or multiple factory-calibrated miniature transducers to achieve a better understanding of changes in oral pressure in the resting jaw position and during swallowing [14]. This system allows the simultaneous evaluation of baropressure changes at multiple locations.…”