The buccinator during mastication: A functional and anatomical evaluation in minipigs

Abstract

Objective-The buccinator muscle forms the lateral wall of the oral cavity. It is presumed to aid mastication by maintaining bolus position. Such a function would involve thickening the cheek, possibly compressing the alveolar bone and contributing to malocclusions. However, neither buccinator deformation nor its effect on pressure has been demonstrated. Our objective was to evaluate buccinator EMG during feeding, its changes in length and thickness, and the pressure exerted on its alveolar attachment, using miniature pigs as an animal model. Methods-EMGof the buccinator and other oral muscles was recorded with fine-wire electrodes. Anteroposterior length and mediolateral thickness of the buccinator were evaluated with implanted sonomicrometry crystals, and pressure was measured by flat transducers placed beneath the mandibular origin of the buccinator. Recordings were made during feeding and muscle stimulation. Tissues were collected postmortem for histology.Results-During mastication, buccinator EMG showed regular peaks that preceded those of the jaw closers. Pattern differences clearly distinguished working and balancing sides. The buccinator shortened and thickened when it contracted. Positive pressures were observed at the mandibular attachment of the buccinator, increasing when the muscle was active. Histological evaluation showed a complex interweaving of fibers closely associated with salivary tissue.Conclusions-Buccinator contraction does thicken the cheek, and during mastication this activity takes place just as the closing stroke begins. In addition to controlling the bolus, there may be an effect on salivation. Despite the fact that the muscle pulls on its attachment, the local mechanical environment at the alveolar bone is one of positive pressure.

Experimental and Numerical Characterization of the Mechanical Masseter Muscle Response During Biting

“…Electromyography measurements could be useful to determine the changes in muscle activation patterns associated with eating and temporomandibular joint disorders [1,46,47]. Moreover, muscle shape changes including shortening and cross-sectional thickening during contraction have been shown to correlate with electromyography data in experiments with minipigs [48]. The present ultrasound data should be evaluated in combination with electromyography data on the same subject using the setup presented by Le R ev erend et al [10] to confirm those findings.…”

Swallowing kinematics and airway protection after palatal local anesthesia in infant pigs

“…). Husbandry and the specifics of the methods of EMG electrode and marker implantation followed Thexton et al This methodology has been used in other pig studies and does not alter feeding …”

“…Husbandry and the specifics of the methods of EMG electrode and marker implantation followed Thexton et al 12 This methodology has been used in other pig studies and does not alter feeding. 9,13 Treatments The day after surgery, experiments began and the animal was placed under 3% isoflurane to achieve deep/surgical anesthesia for 20 minutes. A Weck Hemoclip Ligating Clip (Pilling Weck, Research Triangle Park, NC) was placed on the epiglottis.…”

Sucking and swallowing rates after palatal anesthesia: an electromyographic study in infant pigs

“…The procedures followed for EMG surgery and analysis are those used in several previous studies (German et al 2009;Konow et al 2010;Thexton et al 2012). Analyses of kinematics as well as animal discomfort show that these procedures and instrumentation have minimal, if any, impact on feeding ability in mammals (Dutra et al 2010;Thexton et al 2007).…”