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Mull The buccinator during mastication: a functional and anatomical evaluation in minipigs It is an assistant muscle of mastication chewing and in neonates it is used to suckle.
This procedure was, however, not reliable for dimensional changes, which varied widely in direction as well as in amount when the buccinator was tetanized Table 3. Commons category link is on Wikidata Wikipedia articles with TA98 identifiers.
To insert the anterior and posterior crystals inside the buccinator, muscle fibers were gently separated. Distribution of the maxillary and mandibular nerves and the submaxillary ganglion.
The independence of orbicularis oris and buccinator activity patterns further indicates that despite the apparent continuity of their fiber bundles at the oral commissure, these two muscles in pigs are neurologically distinct. Regardless of the detailed pattern of activity, these studies do support a role in mastication as a principal function of the buccinator.
The buccinator mechanism. Dimensional changes were variable, probably because of distortions within the muscle. The buccinator shortened and thickened when mechanosm contracted. Activity of peri-oral facial muscles and its coordination with jaw muscles during ingestive behavior in awake rabbits.
Buccinator outlined in red. Transition from suckling to drinking at weaning: Buccinator anteroposterior length was an average of 1.
Internal kinematics of the tongue in relation to muscle activity and jaw movement in the pig. Dimensional and pressure changes of the buccinator muscle during mastication a.
Results During mastication, buccinator EMG showed regular peaks mechannism preceded those of the jaw closers. The superficial lateral and deep medial crystals were intended to measure muscle thickness and were placed under the skin superficial crystal and deep to the mucosa deep crystalin the mediolateral transverse plane, about midway between the anterior and posterior crystals.
No distinct pressure variations were seen during drinking in the single individual that performed this behavior. As shown in Fig. Minimum length and maximum thickness and pressure are typically reached during the jaw closer burst, illustrated by the right masseter RM. A major reason for the less regular pattern for non-pig chow foods was the presence of additional strong bursts of buccinator activity, often occurring as the jaw-closer burst was ending Fig. Low activity often continued on both sides throughout the jaw-closer burst Fig.
Leuven University Mechanizm An anatomical study of the buccinator muscle fibres that extend to the terminal portion of the parotid duct, and their functional roles in salivary secretion. The incisions were sutured and the cables connected.
Peaks of pressure corresponded with minimal anteroposterior lengths and maximal thickness both in food gathering and in mastication. Procerus Nasalis dilator naris Depressor septi nasi Levator labii superioris alaeque nasi. Sonomicrometry crystals in the buccinator small ovals within dotted circles were placed anterior 1posterior 2superficial 3 and deep 4. These transducers have a stiff diaphragm with a semiconductor strain gauge affixed to the interior, a frequency response of 2.
After a period of acclimation 3—5 daysEMG activity of the facial muscles buccinator and orbicularis orisjaw closers masseter and temporalis and in two of the pigs jaw depressor digastric were recorded bilaterally during normal mastication. Nevertheless, as also reported for humans, 30 in histological sections fiber orientation is highly complicated. Shcherbatyy V, Liu ZJ.
Concurrently, resting pressure at the mandibular attachment buccinafor the buccinator was higher in anesthetized animals, averaging 0. An evaluation of buccal shield treatment. The dimensional changes observed during function indicate that when the buccinator contracts at the beginning of jaw closing, the primary change is an anteroposterior shortening, which further causes a retraction of the corner of the mouth and, most importantly, an increase in the thickness of the cheek.
LBuc is the stimulus recorded through EMG electrodes in the left buccinator. Table 3 Stimulation of the buccinator in anesthetized pigs, resting vs contracted dimensions and pressure a. Pigs were anesthetized as usual and positioned in lateral recumbency.
They also saw low activity from the buccinator before the masseteric burst, and this was probably genuine. The buccinator muscle forms the lateral wall of the oral cavity.
Although buccinator fibers attach to both upper and lower jaws, their predominantly horizontal direction indicates that the muscle is not a jaw closer. Because of the close relationship of the buccinator with the orbicularis oris, EMG of this muscle was examined as well. During mastication, buccinator EMG showed regular peaks that preceded those of the jaw closers. Thickness strains were roughly half as large as length strains, i. The buccinator during mastication: a functional and anatomical evaluation in minipigs Physiology of feeding in miniature pigs.
In addition to controlling the bolus, there may be an effect on salivation. EMG for drinking orange juice compared to mastication orange slices inthe only pig that drank. These elevated tetanic pressures corresponded to the contraction of the muscle and were sustained until the end of each tetanus Fig. During feeding, baseline loading approximated 0 in all animals, and changes from this level were always positive, i.
Food gathering showed similar EMG patterns for all types of food Fig. Rabbits have a much broader transverse movement during the power stroke than either humans or pigs, and the jaws are so anisognathic that there is no tooth contact at all on the balancing side. Salivary tissue was found throughout most sections, even between the buccinator fibers Fig. TOP Related Posts.
BUCCINATOR MECHANISM PDF
Arazshura Anesthetized pigs were euthanized with pentobarbital mechznism the end of the terminal experiment. Therefore, in order to better understand the function of the buccinator during mastication and the effects on the alveolar bone, we undertook a study using minipigs Sus scrofathe nonprimate animal model most appropriate for the study of human mastication. Table 3 Stimulation of the buccinator in anesthetized pigs, resting vs contracted dimensions and pressure a. Most likely, the muscle functions by thickening the entire cheek, basically acting as a muscular hydrostat.