IADR Abstract Archives

Impact of Palatal Anesthesia on Muscle Activity Timing during Swallowing

Objective: The role of sensory information from the oral cavity on swallow initiation is not completely understood. We hypothesized that palatal anesthesia (PLA) reduces swallowing frequency, delays the onset of swallowing and changes the timing of motor output during a pharyngeal swallow.

Methods: Eight infant pigs had electromyographic (EMG) electrodes placed into mylohyoid (MH), thyrohyoid (TH) and cricothyroid (CT). They were bottle fed milk while recording EMG after receiving one of three treatments: nerve blocks to the hard palate of (1) saline (PSA); (2) 0.5% bupivacaine hydrochloride (Marcaine) (PLA); or (3) control (no injection). We tested for timing differences in the EMG signal using ANOVA.

Results: After PLA, four of the eight pigs chewed as opposed to suckled (chewers). In these pigs there was more time between swallows relative to control (p<0.001). In the non-chewers with saline treatment there was significantly less time between swallows compared to control (p<0.001). In the chewers, with PLA and PSA, there was less time between MH and TH, or before the onset of pharyngeal phase as compared to the control (p<0.001 and p=0.024 respectively). There was also less time between MH and TH in the non-chewers with PSA relative to control (p<0.001). In the pharyngeal swallow there were statistically, but probably not functionally, significant increases in time between TH and CT in the non-chewers with PSA (p=0.019) and PLA (p=0.030) relative to control.

Conclusions: The lack of functionally significant difference between TH and CT signals suggests that once a swallow is triggered the pattern of muscle activity is not affected by changes in oral sensation. However the lack of palatal sensation (PLA) or heightened palatal sensation (PSA) changes the frequency and onset of the pharyngeal swallow.

IADR/AADR/CADR General Session
2013 IADR/AADR/CADR General Session (Seattle, Washington)
Seattle, Washington
2013
2252
Craniofacial Biology
  • Waranch, Danielle  ( University of Maryland Dental School, Baltimore, MD, USA )
  • Holman, Shaina Devi  ( University of Maryland Dental School, Baltimore, MD, USA )
  • Campbell-malone, Regina  ( Johns Hopkins University School of Medicine, Baltimore, MD, USA )
  • Ding, Peng  ( Johns Hopkins University School of Medicine, Baltimore, MD, USA )
  • Lukasik, Stacey  ( Johns Hopkins University School of Medicine, Baltimore, MD, USA )
  • Gierbolini-norat, Estela  ( Johns Hopkins University School of Medicine, Baltimore, MD, USA )
  • German, Rebecca  ( Johns Hopkins University School of Medicine, Baltimore, MD, USA )
    • Poster Session
    Muscle, EMG
    03/22/2013